gmw.conservation.ca.gov€¦ · 16/09/1985 · COUNTI OF ALAMEDA PUBLIC WORKS AGENCY 399 Elmhurst...

COUNTI OF ALAMEDA

PUBLIC WORKS AGENCY 399 Elmhurst Street •Hayward.CA 114544

(415)881-6651

BUILDING INSPECTION DEPARTMENT

Mr. Robert W. Brown Senior Building Inspector City of Fremont City Government Building Fremont, CA 94538

Dear Mr. Brown:

NJ!I 6 78 AM ffP-~

June 2, 1978

As requested by the City of Fre!llont, the geotechnical investigation reports and correspondence prepared for the Fre!llont Meadows property have been reviewed for conformance with the provisions of the Alquist-Priolo Act and generally accepted geotechnical practices.

Documents reviewed were the following:

1) Fremont Meadows Active Fault Investigation and Evaluation, report prepared by Woodward-Clyde and Associates, dated June 1970.

2) Preliminary Evaluation of Liquefaction Potential, East Portion of Fremont Meadows Property, report prepared by Woodward-Lundgren.and Associates, dated February 1975.

3) Letter to Alpha Land Company from Mr. Wayne E. Ferree, Terratech Inc. dated November 8, 1977.

The review consisted of a careful study of the various documents submitted, an inspection of the site and adjacent areas and an examination of aerial photographs applkable to the property.

The reports submitted contain s.ubstantial information which is, in my opinion, sufficient to establish the location of the main traces of the Hayward Fault system within t:he Fremont Meadows property. Although the Fremont. Meadows Active Fault Investigation and Evaluation report was prepared prior to enactment of the AlquistPriolo Act, it is my belief that this report provides satisfactory compliance with the intent of the Act. - - _,,____ - ----·-- ... ·----· --- --·- ~

The Preliminary Evaluation of Liquefaction Potential report indicates that while some potential exists for differential settlements within the area studied, during a major earthquake, this hazard can be mitigated by special construction techniques.

Alth_ough the existing reports appear to adequately address the major geologic issues. which affect the Fremont Meadows site, there are several items which. I believe

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Mr. Robert w. Brown -2- June 2, 1978

the City of Fremont should carefully consider during evaluation of land use and development plans for the property.. These are as follows:

1) The activity status of the easterly fault trace has not been entirely established. Trenches excavated by Woodward-Clyde and Associates indicated that the easterly trace was encountered at progressively greater depths toward the southeast and could not be observed in carefully logged trenches located within the southerly portion of the site. However, high resolution aerial photographs (Pacific Resources Inc. AV 50-08-01 and AV 50-09-01 dated November 22, 1950) show a distinct lineament across the entire property which correlates with the fault trace. Logs of test borings included in the 1975 study by Woodward-Lundgren and Associates indicate that the thickness of the fine-grained, near-surface alluvial deposits encountered in B-1 east of the projected fault is about twice that of the same materials encountered in borings 2 and 3 located southwest of the projected fault. This difference in thickness may be related to the effects of ground movements along the eastern fault trace. C-14 dates included in the Woodward-Clyde Associates study indicate very high sediment accumulation rates at the Fremont Meadows site. Net accumulation rates of one foot per 300 to 400 years are indicated for deeper strata and therefore trenches as deep as 37 feet would be required to reach the inferred base of Holocene materials (last 11,000 years) based on these sediment accumulation rates. Such trenches are obviously infeasible and therefore, the recommendation by Mr. Ferree that a 50 foot-wide setback zone be established across the property along the southerly projection of the eastern trace is prudent and should be enforced by the City of Fremont.

2) It is my opinion that there is a high potential for the development of cross faults, lurch cracks, etc., in the area between the two main traces of the Hayward Fault. This includes the areas identified as Zones 5 and 6 and the portion of Zone 3 located between the fault traces (including the southerly projection of the eastern trace) as defined in the 1970 study. Model studies performed by Woodward-Clyde and Associates indicate that the development of such cross faults is probable and aerial photographs show faint lineaments which may represent such faults. Fracture planes such as those at Stations 26 and 266-268 in Trench J appear to be minor cross faults.

Thellfore, it is recommended that a qualified structural engineer review foundation and building plans on behalf of the City of Fremont to assure maximum mitigation against the hazard of minor ground movement along subsidiary faults. For the purposes of estimating the level of hazard, the data contained in Tables 1-3 in the 1970 Woodward-Clyde and Associates study represents judgments which are as '<·informed as any. It is recommended that the data for Zone 6 be applied throughout the area between the fault traces as a matter of proper caution.

3) The recommendations for future soil investigations contained in Mr. Ferree's letter appear generally reasonable if it is assumed that the large fill mound on the site is to be removed or used as material for properly engineered fills. This is implied but not specifically stated in Mr. Ferree's letter. Also, it is recommended that the stability of soils underlying the northern part of the Fremont Meadows property near Walnut Avenue be required to be further

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.. Mr. Robert W. Brown -3- June 2, 1978

assessed if any building is planned in that area. This recOllllllendation is made because of the presence of periodic standing water in low areas in and near this part of the site and because th.e lows provide free faces into which the soils could move by lateral spreading during a major earthquake, None of the test borings made during previous studies were located in the northerly portion of the project area.

Costs for this review are $250.00. These will be charged against the trust account established by Alpha Land Company· with the Alameda County Building Inspection Department. I have appreciated this opportunity to provide geological review services for the City of Fremont and would be pleased to do so again if desired by the City of Fremont.

Very truly yours,

~ ,,_;J \,) ' ~-it't-0\ David W. Carpenter Alameda County Engineering Geologist R,G, #248 C,E.G. #135

DWC:dv

City of Fremont City Governinent Building Fremont, California 94536

State Division of Mines and Room 1009, Ferry Building San Francisco CA 94111

Geology

1) LI tJ ;) '•l 7" •\·'f J

S~n Francisco, California

June 7, 1978

Attention: Earl w. Hart, Office of the State Geologist

RE: Geotechnical Investigation for Fremont Meadows, Stevenson Boulevard at Civic Center Drive, Fremont

Gentlemen:

Enclosed for your file are the following documents:

(a) Fremont Meadows Active Fault Investigation and Evaluation report prepared by Woodward-Clyde and Associates, dated June 1970.

(b) Preliminary Evaluation of Liquefaction Potential, East Portion of Fremont Meadows Property report prepared by Woodward-Lundgren and Associates, dated February 1975.

(c) Letter to Alpha Land Company from Mr. Wayne E. Ferree, Terratech Inc. dated November 8, 1977.

(d) Geologic Review by David w. Carpenter, Alameda County Engineering Geologist dated June 2, 1978.

Very Truly Yours,

" /. '%(./.

ROBERT W. BROWN Senior Building Inspector

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cc: Alpha Land Company

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C .I TY: T' r ~~1no11. L 1\ rt 1 n:

COUNTY: Ala.mecla

l'l.ANq{.Nr; ,> ENCIREEIUNG, Gustaf>;<Hl 9.ll'l' SPONSOH: Alplla Land Company

S L:l\J EC'I': 11\ID /J.rlt, 11 121-342 36 STATUS: J\'.';p - J

I.. () Exltlb:i ts arc . .\c<:eprnhle (St~r: l.i)mn:t.~nt:·u He.low lf Not Acceptable)

J, tp Site In~p"~tion on: 10-5-77

Exhibit t; Rev icwcd: ~H: i 11- , . 77

Fre1nont M{~;uJows

(1) Active Fault Invcst:igat.ion rend Evalu:. t~bh'-ll ·_:wo'o~twr;rrt_:;: M;sodatcs dated June 30, 19'l0

(2) T~.rcliiainary Evaluati(ln of Liguefaction rotenti;:.~.l.J .East portion of; Fremont Meadows Property by Woo(iwa.rd-I.t1Itdgi·e.n i.1.lld Assoc.iat~t;

(3) Prediction of 1naxi111um earthquake :llntcn~·:;ity .i.n the .SaJl Prancisc0 l~ay Region, Map Ml'-709, VSGS l 975

(4) Studies for Seirni(; Zon.a .. tion of the Sa.n r:ranci~~co Day Region~ USGS Professional Paper 941-A, 1975.

(5) Off i.r:i al M"p of Special Stmlieo Zone,; for Niles Qua<frangle by Sta tc Geologist, ,Tuly 1, 197'1.

(6) Prclilliinary Site Plan by Ch,,rles W. Dell< and At;s()(:i,,tes, Dated July 18, 1977 (7) Grading Plan by Murray-McCormiclc dated March 1973.

Com.inent s /Background

1'11c $Ubject .site is travcrsei.1 by mojt'tii + t···;1H_~ of the I-Ii.iyward Fault a.s approxi~

mately l<)f;aled on tl1c State <.;eologist 1 ~ Cl[ficial Mi:t.P (f:!.xhibit 5)1 '.L'here is con~;iderable evidenGe frorn previous topograpl1ic, geophysical, groundwate:r and other ~.:;tudie.s fi·o1n a

·number of :::,ources which support these mapped location.',;. Th~~ specific on-f;ite location of thE:: fa.ult trace or t1~acc.s are ciel.inatf:!d in the geologic t.;tudy by Wof.>c.iward-Clyde (Fxh3,bit1).. As indicated in th.i~·:; c~port, tl1er.·c is clear evidence of pr.evious fauli:.ing ancl di~-;1)1<1..cemcnt along tl1c Western tract..~, but ~·'' n•Nil 81.'!l"l"fen .. c 11.1p:Wi.~~g the I! ~"'>liti•H ·L·sa.n 1~ ui""t-"!l±n-e'lre inst U i~f:I: ytTI.'~ ( i.:i.l though flexur~ll 1..tis tort.ion. was found in the upper alJ.iult'ial bcd(iinr,- ;;i..1 ong th~ north end of the. site)~

In adcii Lion to displace111ent and clistor±ion c.a.u~;.ed by pi·cviou~~ eartl1quake~:;, there is considcr~tblc evidence of fau.l. t cret~p in the gf~rlel.'i:ll area a.!S d<.Jctuncnted by nurnerous sources.. As observed in the f-.. ld, t.l1crc app~ars to be an indication of 1)reviou.s creep along thr: .._ta I t;f of t11e fau;{\'.cor at .least liitcral ground d.istortion west of that fa.Ltlt tra~:e). 'I'll i~; ha.~;t-~l~n the pi:-e.se.nt alinern~nt of the existing: power, poles near the northern boundary of the eastern ~ortion of the property. All of these poles ( 1nost oi· c.ll..l of which are ::.;hown on Figure 23 of l\xhibit 1, as rnapped by Murr11,y a.rid ~c.Corm.ick in l(J?O) art~ ~n nearly p(~t:f~ct alincrncnt (~~~.:;~;ent:ial.ly alnng an cast-wet;t li1·1c) except for the la.::;t twu on tl"ll:: wef;"L1.:~rly cnct. W~~thout bcni;:~fit of suJ":"veyinc iHst.rtuncnts, a di~;t.inct off~;e:t ( in a right l~i.t~ral sense) of about 2 ff~et can 'be observed between the 8e\:<.)rH.l pole and tl1c :rernainir1g poles to the east, an<l there is even greater offset in th~ fi.rt;.t pole (westernmost). I have no fi1·st hand infC.irrnation in reference to th~ original in::;tallation~ but the polt.~s wer~ aµpar.·cn1tly install~d a nu1nber of year.:-; agn and it S(:CHl.:3 rca;~ona .. ble tlla.t they wt~re all placcc.l in the SiuUo alinc1nen t.

As ~~fH.~wn on the Pre.li111inary ~)tie "Pl:u1 (1'.xl·iibit G) the portion of the presently plL.UlrlCd over;ill dcvelop1ncnt under l1llD application is co1npri!3.:=.~d of condominiu1n'.:; uni ts l~)tatei..i

on the easterly side of the site (~ast of t11e westerly trace of t11~ Fault). A c:ou1111crcia.1 ~:;hopping area .i~:; p.1.~i.nncli on Lhc remaining portion (westerly of the fault ~. traces). A~:; further irH'licat~d, two .:_;(~p(~rate ''Sc:i.rnic Zon~~~;I' arc shown on the plan; th~.~sc are in effect building ~:;.ct \.lack zone,,·_.:, pre~:,u111ably ''centered'' over the wf;!:Stern and ea~~tern fault..., __ _

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326 COMMERCIAL ST.

Alpha Land Company 2925 Scott Blvd, Santa Clara, CA 95050

Attention: Mr. John Griffin

Subject: Fremont Meadows Seismic Hazards

Gentlemen:

SAN JOSE, CALIFORNIA 95112 (408) 297·6969

November 8, 1977 Project 9038

As requested, I have reviewed the memorandum prepared for Mr. Stan Moen by Mr. Hugh Gustafson regarding the geologic hazards to the subject property. Also, I have reread parts of the two reports prepared by Woodward-Clyde and Associates and their consultants, referred to by Mr. Gustafson In his memorandum.

Mr. Gustafson's concern over the geologic hazards of the property proposed for development is valid~ The site is crossed by an active strand of the Hayward Fault system and lt l les adjacent to a second, less active fault trace. While I agree with Mr. Gustafson's concern, I believe all questions of seismic and geologic risk raised in his memorandum have been fully considered and answered in the two studies by Woodward-Clyde and Associates.

The particulars of building foundation design was only touched upon in the first study, but considering the type of structure (2 story wood frame buildings) and the type of foundation proposed for this residential development I bel ie've that a sufficient amount of subsurface information (data relating to soil properties) h~s been collected to undertake foundation design. Prior to actual construction, additional surface samples should be collected and tested to measure the important properties (comperssion-swell index, compaction characteristics and "R" Value) of the near-surface soils, but I see no need to explore the deeper soil zones with a drilling rig or backhoe.

Before responding to the individual questions raised In the October 12, 1977 memorandum, I wish briefly to comment on the Woodward Study. In my opinion this particular study is one of the roost cornplete and thorough studies of its

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November Project ~ z -

8. 1977 9038

kind that I have read. In fact, one reading of the report may provide the reader with useful information, but the report should be studied to fully utll ize the data collected and the planning concepts-Pr-esented. I was not one of the study authors, and therefore cannot claim to be. "The Authority:• In interpreting the findings. However, I am a professional engineer and geologist, experienced in foundation engineering, and in my opinion, after carefully reading the W.C. and A. report, I believe the proposed residential development c~n be safely constructed on the property If the guide I ines es tab Ii shed by the Woodward report are fol lowed. The seismic risks associated with site development cannot be completely el lmlnated, but they can be mitigated.

The financial cost as well as the time required to conduct the "text book" study of the project site must have been substanti<1l. I doubt that such a study could ever be justified economically except for commercial or Industrial developments involving the planned construction of expensive and complex buildings or structures. Having such a complete study available for the planning of a low rise residential project is fortuitous.

The four major items of concern as listed in the October 12, 1977 memorandum of Mr. Gustafson are:

l. Fault rupture

2. Creep

3, Liquefaction

4. Severe ground shaking

All four hazards are interelated, but I will discuss eac.h separately.

l. Fault rupture. In essence, the bulk of the original 1970 Woodward Study was designed co accurately locate the active traces of the Hayward Fualt System through the property. This was accomplished! The western fault trace has been located withn a narrow band ranging from about 20 feet wide on the northern end of the property to a maximum width of 75 feet at the southern boundary. The eastern fault trace is equally well defined north c>f' the property, but the trace completely dies out just south of the northern boundary of the Fremont Meadows property. The Investigative tools used In the W,C & A study of the Hayward Fault system Included stereographic studies of aerial photographs; detailed surface mapping of geologic features; geophysical exploration (magnetometer and seismic refraction surveys); drilling and logging of numerous smal I diameter test borings; study of the groundwater system;

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November 8, 1977 Project 9038 - 3 -

excavation of numerous test pits and trenches; age dating organic samples using the carbor 14" technique; and also constructing a physical scale model of the Hayward Fault system as mapped by the study.

The are~ covered by this detailed investigation extended wel ( beyond the physical l lmi ts of the property, and the authors incorporated data collected off site by others and well as from their own studies of other projects.

Based upon the evidence suppl led, and the confirmation of their findings by the dynamic behavior of the site fault model, the conclusions of the study seem irrefutable (see pages 24 through 36). The Hayward Fault zone at the project site consists of two discontinuous fault traces. The western trace is discontinuous to the north, and the eastern trace is discontinuous to the south. The fault features in the immediate vicinity of the property have been created by the transfer of fault movements between these two discontinuous strans and not by movement along two continuous and parallel traces as· originally postulated. The western trace Joins the eastern trace some 3000 feet north of the property through an active cross fault.

The western trace within the property is a well defined, narrow and active fault. From carbon dating, we know this fault has been moving for at least the last 2400 years.

ln contrast to the western trace, the eastern trace within the property comple~ely dies out just south of the northern property l lne. Even north of the terminal point, the fault shows little sign of geologically recent activity and the trace shows "little potential for propagation south of Its present location." Given the relative activity of the two traces (no movement on the eastern trace and cont I nuous movement for some 2400 years on the western

·trace), there is no reason to believe the pattern of faulting wil 1 suddenly change.

Considering the relatively narrow width of the wet l defined western trace, a 50 foot building setback l lne from the edge of the fault boundary should be adequate to reduce the rl•k of fault rupture under a building constructed on the site to an acceptable level. A similar setback along the eastern trace cannot be defined because the fault does not actually cross the property. However, the potential risk of movement along this trace Is also quite low (see report pages 54-55), therefore an arbitrary 50± foot setback from the projected fault centerline should provide an equivalent degree of protection against the risk of ground rupture through a building.

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November 8, 1977 Project 9038 - 11 -

A considerable amount of discussion In the WC & A report ls devoted to the risk of ground rupturing along branch and cross fualts, especially in the zone between the two fault traces. The report concludes that potential magnitude of horizontal deformation In Zones 6 and lower (most of the planned area to be developed is in Zone 3 and Zone 1) during a maximum credible earthquake is 4% or less. In Section 11 of the original report, the structural engineering evaluation portion of the study, a table has been prepared relating the type of building (height, use and construction materials) that could be constructed within each zone. With proper design the authors indicate that multi-storied buildings as high as 10 stories can be safely sited on areas zoned 3 or less.

The key to building within a zone of potential cross faults is to design buildings so as to reduce potential damage should those buildings experience rotation, horizontal displacement, or differential settlement. This can be accomplished by constructing a stiff, rigid, high strength foundation system for each structure. For a. low mass, energy absorbing, low rise, wood frame building, this is not a difficult design problem. The buildings proposed can be supported on a reinforced slab, stiffened with deep rigid, reinforced perimeter footings and cross footings. This is the type of foundation sys tern a I so recommended In the report (Sect I on I I, page 26). Such a system is substantially stronger than the supporting soils, and therefore ml~or fault off-sets in bedrock that ls covered with several hundred feet of alluvium would not 1 ikely cause a shear failure in the bui l<lings foundation (see report Sect l on I I , page 3 and 4). The surface meanders of fau It induced ground rupture around stiff foundations, street pavements and concrete slabs have been noted in many recent major earthquakes. Even in the case of fault rupture or creep through a zone crossed by a relatively weak, but long structure (curb and gutters, sidewalks, etc.) the point of failure usually occurs in a j~int close to the line of rupture.

2. Creep. The term "creep" in a seismic sense refers to the per·sistent but slow differential movement that may occur along an active fault rupture plane. Each site of active creep noted in the report is aligned along a known fault trace. If the width of suspected zone of active or potentially active faulting is excluded from the building area, creep should not be a serious post construction problem in the planned development.

The mlsal ignrnent of the power pole> noted by lir. Gustafson, I believe reflects the original construction alignment rather than recent ground movement. The westernmost pole is located directly adjacent to the base of a low mound in the property center. Visually the last three poles on the western side seern to be fairly wel 1 aligned, suggesting to me that a slight angle change may h~ve been made in the last two poles during installation to avoid the mound.

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3. Liquefaction_. In my oplnlon,the possible hazards to the proposed low rise development related to foundation 1 iquefaction are quite well discussed In the supplemental study by Woodward Clyde and Associates, prepared in 1975. There are some sands in the subsoils that could conceivably densify during ground shaking from a major earthquake. However, the most serious result of such denslfication, should -it.ever occur, woul<l be the vertical settlement of the ground in response to a soi 1 volume reduction. SLJch settlement would have an order of magnitude of several Inches, with maximum potential differential settlement across the building, also I imited to several Inches. In comparison to the potenltal shaking damage from a major earthquake that could occur to other residential buildings constructed in the Bay Area and designed to UBC standards, such settlement problems wi 11 be minor. If supported on the proposed rigid foundation system, slight shifting or settling of a building should not constitute a severe or expensive seismic hazard. utl 11.ty service to the bui I ding may be disrupted, but this could also occur at sites with no I lquefactlon potential. Utll lty service 1 Ines can be constructed with automatic shut off valves to mitigate the hazards of broken gas, water or electric service 1 Ines.

4. Severe ground shaking. If in fact, the site does contain sand lenses that will den~ify under severe shaking from a seismic disturbance, then severe shaking of the surface sol ls and buildings occupying the site wi 11 be 1 imited to the stress level at which the sand liquefies. The liquefied sand will have essentially zero strength and therefore wll l be incapable of translating any earth~uake induced shear waves to the ground surface. The SQnds, if they do denslfy in response to ground shaking wll 1 act as ~limit switch shutting off dynamic shear stresses above the level of a moderate earthquake.

If the sand layers do not 1 iquefy, and they may not, ground surface and all buildings constructed on the site will be subjected to 'dynamic loads from ground vibrations. These vibrations may be severe, but should be no more intense than that experienced at a considerable distance from the fault. The state 6f the art of earthquake engineering changes daily, but I believe the information and examples presented in the report relating to variation in the intensity of earthquake induced ground motion with distance from the causative fault is still val id (;ee report appendix B, P<ige 7-12). In my judgement,the buildings proposed for the site should respond to internal forces from ground shaking as successfully as other similar residential buildings constructed on nearby sites. In all probability, because of their stiffened foundation system, the proposed buildings will survive a major earthquake, should it occur during the economic 1 lfe of the project, with less ·damage thJn similar projects.

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November 8, 1977 Project 9038 ~ 6 - .

CONCLUSION

In conclusion, I see no reason why the Fremont Headows property cannot be developed with residential bui !dings. If the guidel Ines established In the Woodward report are followed in terms of risk zones and compatible construction, ~nd in particular if the active zone of the western fault trace is not developed with habitable structures, the potential hazards from seismic activity should be reduced to an acceptable level, similar to that now assumed for residential buildings constructed to minimal UBC standards (less substantial foundations) on sites located at substantial distances from actual faults.

Both reports do suggest further studies be made prior to site development, but this remark refers to a comrnercial and/or industrial developemnt with high foundation loads and complex structures. The design of such structures ...,u]d require knowledge of the engineering properties of the supporting soils that is not required for the I ight weight ·1ow rise structure now planned.

Very truly yours,

TERRATECH, I NC.

lv<'~i,.-..t r· 6-Q/vUL{' Wayn•{·. Ferree RE 17 02

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DEPARTMENT OF HOUSING AND URBAN DEVE\..OPMENT

~EGION IX 450 V<>Jdtrt1. Gille A'lli!nue

P.O. IJoii J600J S•i:i- F'flll!'IC1Aco, Calllornh1 9'6102

AR!:;A OFFICE

ONE EMBAH:CADC:~O CF.NTER, S.U!TE \600

SAN P~ANC!SCO, C:Al,,IFORNIA 94111

November 15, 1977

Alpha Land Company 2975 Scott Blvd. Santa Clara, California 95050

Attention: Mr. John Griffin

Subject: FHA Project #121-34236 Fremont Courtyai·d Fremont, California

Dear Mr. Gi·iffin:

.>t:CEI'

N~JV l 71J77 11.IPVt. I t,>.i.1 '·1N ~'t(1-:11...'t' REFER TOt

Richard Sekiguchi Subdiv, Appriaser (415) 556-4546

I have i:-eviawcd Mr. \Jay11e Ferree's report of 11/8177 on seismic hazards in this dnvclopment. I have also visited the site and recognize the value of a well designed housirig project in this area. We ar.e all aware of the seisn1ic hazards in the Bay Ar"a, the risks itwolved on specific sit~s an<l also th~ ne~d for muderatcly priced housin!;. Based on these concerns we shall procc.ed wi.Lh the proc~~ sing of this proposal.

Prior to is.suance uf our final (:iprroval our i.-cg1 onal Structural Eng,in(~cr n111st rc.vit~w anJ upprove your foundation de.sign for tl1(1.se units. P1ocesslng of this proposal has b~~n r~sumeJ effective this dnte .

"'~(0tC.....___ St,wley II. Moen Chid Single Family Brant:h

. , : , .. '' ~··fl .,.. ""l'~'.'I'"'•'·' ,, .,,, ., ,.,·,1; ,,.,.,,,, ., .. · ,,,,, .• ,_.~,. < ,, .. ,."'"''''~"''"'"'~········'· -' ,,,,.,.,, ......... , ..... ,, ........... , ... . ,,~~""··-,-.---·~·--··-·:· ····'r:-:--,-·----···::-·-·----.---·--------·:-· .. ·-... -··. ·- ••• ••·-~----·~--. -, --M·'••••" • "",,~··----··--r-••• ... :.:::: ... : .. : ... ::.....'.~.--·-~···-~·-~·_, ..... ;,.~..:~.~---·~·:;;==i.

~ ~ -· - .. r:.' ~.. Page Two • • .; ·A l~ift1cfuct.iun study wa~; rccon11n~~nC\ed for t1·1e ea~·; te:rn portion of the site in the

1..)r:i.einal geolig.i.c report (l;.xlii\)itl). A pre.timin.ary study wa.s lnade a.nd teported in February 1975 (Exhibit 2), whl~.tcin it was concluded that the potential for liquefaction of the underlying cra.nula..r sc)ils was moderate to high in the event of a majo.r;- ca.rthquakc along the lln.y.,.,Jard fault. A~> secondary effects of liquefaction, tt1e poter1tial for lateral movement or spreading was considered low; however, p1ltcntial ~ettlement c>ver ~cveral inct1cs was estimated. final evaluation of the pi..itenti~:1.l for .later~tl 111ovement ri.nd settlement/differential settlement would z.'equi:t'c extensive sub.!$Utface ~.;oil~:; explo.ratior1.

Con cl u .~:.ion~:. /Re couunenda t j,on s

Based on presently available infonr1ation relating to potential seismic h"zards a.ssociate<i with this c;ite, we do not recommend HUD approval of the proposed development for insuring purposes. The following specific reasons are cited:

CU Detailed geologic investigations demonstrate that one major act1 ve trace "f the llayward fault \'as:;es through the site •md another major trace penetrates w1d possible passes under the surficial "oils of the site. In addition tu ground rupture and displacement along the main fau.J.t traces, there are numerous rela~cd.

eff ccts involving branch o:i; secondary faulting:11 and: adjacent_ground distortion and deforn1ation_ The degree and dimensional lirllits of th8.sc rel1ted effects cannut be reliably predicted. (2) Cor1trary to earlier assu1nptions:11 more recent evide11ce dP.Inonstratts that g:roundshaking is t5ignific<u1tly greater in areas adjac~nt to the causative fault (refercnc<: page A-38, Exhibit 4). This project site is located in Zone "A" a'; designated under Map MF-709 (Exhibit 3) which is considered subject to "ve.-y vi.olent" earthshaking intensitie" (worst case). (3) Based on the preliminary analysis, the foundation soils are ~ubject to liguef action which would probably result in considetable settlement and differential settlement of the #' ft ,9.r•""~ • (4) There i$ clearly established evidence of tectonic crepp along muel' of the Hayward Fault with some indication of creep ac.-oas the project site. 1nformation on the rate of creep and the width of the creep zone in tile area has not been )Jrovided, but long term creep can be seve:rly damaging to structures.

It is concluded that th.ts site is subJect to significant seismic hazard8, and that development of tl1e site WllUld result in excessive risk8 which should not be assumed.

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I I I I I I I I I I I I I I I I I I I

GEOTECHNICAL ENGINEERING SERVICES FOR

CIVIC CENTER OFFICE PARK FREMONT, CALIFORNIA

I I I I I I I I I I I I I I I I

I I

Peter Haldueer and Associates, Inc. Geotechnical Consultants

425 ROLANLJ WAY, OAl<LAND, CALIFORNIA 94621, 415/568-4001

Baker Sinclair, Incorporated

September 16, 1985 K893-l, 07524

901 Mariner's Island Boulevard, Suite 315 San Mateo, California 94404

Attention: Mr. Richard C. Baker

Gentlemen:

RE: GEOTECHNICAL ENGINEERING SERVICES


In accordance with your request, we have performed geotechnical engineering services for the proposed Civic Center Office Park. The accompanying report presents the results of our field investigation, laboratory tests, and engineering analysis. The soil and foundation conditions are discussed and recommendations for the soil and foundation engineering aspects of the project are presented. The conclusions and recommendations contained herein are based upon applicable standards of our profession at the time this report has been prepared. Copies of this report are furnished only to provide the factual data which were gathered and which were summarized in the report.

We refer you to the text of the report for detailed recommendations. If you have any questions concerning our findings, please call us.

RLB/PK:jb Copies: Addressee ( 4)

Very truly yours,

~~V\E,,4!.~A~N~D~A--S~so_._c_._·_INC. Ronald L. Baj uni Pro ect Manager So En eer EIVl!Miia

Peter Kaldveer Soil Engineer CE# 19168

Tai Associates/Architects (4) Attention: Mr. Mike Fowler

Leong-Razzano & Associates, Inc. (1) Attention: Mr. Milt Leong


GEOTECHNICAL ENGINEERING SERVICES

For CIVIC CENTER OFFICE PARK FREMONT, CALIFORNIA

To Baker Sinclair, Incorporated 901 Mariner's Island Boulevard, Suite 315 San Mateo, California 94404

September 1985


TABLE OF CONTENTS

Page No.

Letter of Transmittal

TITLE PAGE

TABLE OF CONTENTS

INTRODUCTION 1

SCOPE 1

SITE INVESTIGATION 2 A. Surface 2 B. Subsurface 2 C. Groundwater 3 D. Geology and Seismicity 3

CONCLUSIONS AND RECOMMENDATIONS 5 A. Earthwork 6

1. Clearing and Site Preparation 6 2. Well Removal and Capping 7 3. Engineered Fill Layer 7 4. Temporary Construction Slopes 7 5. Sub grade Preparation 7 6 . Material for Fill 7 7. Compaction 8 8. Trench Backfill 8 9. Drainage 8

10. Construction During Wet Weather Conditions 8 11. Guide Specifications 9

B. Foundations 9 1. Footings 9 2 . End-Bearing Piles 9

a. Vertical and Uplift Capacities 9 b. Indicator Piles 10 c. Pile Driving Criteria and Installation 10 d. Specification and Construction Observation 11

3. Structural Mat Foundation 11 4. Interior Slabs 11

a. Office Area At-Grade 11 b. Office Area Below Grade 12 c. Gargage Area At-Grade 12

5. Basement Walls 12 6. Lateral Loads 13

a. Footing and Mat 13 b. Pile 13

C, Characteristic Site Period 14 D. Pavements 14 E, Construction Observation 15


TABLE OF CONTENTS (Continued) Page 2

FIGURE 1 - SITE PLAN FIGURE 2 - REWORKING REQUIRED FOR 7-STORY BUILDING WITH

BASEMENT ON FOOTING FIGURE 3 - REQUIRED REWORKING BENEATH MAT FOUNDATION

FOR 7-STORY BUILDING

APPENDIX A - FIELD INVESTIGATION A-1 Figure A-1, Key to Exploratory Boring Logs Exploratory Boring Logs (1 through 12)

APPENDIX B - LABORATORY INVESTIGATION B-1 Figure B-1, Plasticity Chart and Data Figure B-2, Consolidation Data

APPENDIX C - GUIDE SPECIFICATIONS - SITE EARTHWORK C-1

APPENDIX D - GUIDE SPECIFICATIONS - PILE FOUNDATION D-1

APPENDIX E - GUIDE SPECIFICATIONS - ASPHALT PAVING E-1

,.


GEOTECHNICAL ENGINEERING SERVICES FOR


INTRODUCTION

In this report, we present the results of our geotechnical investigation for the proposed Civic Center Office Park to be located east of the intersection of Civic Center Drive and Walnut Avenue in Fremont, California, as shown on the Site Plan, Figure 1. The purpose of our investigstion was to evaluate the foundation soils and provide recommendations concerning the soil and foundation engineering aspects of the pl'oject.

Based on the information indicated on the Site Plan as well as on oul' conversations with Mr. Michael Fowler with Tai Associates I Architects and Mr. Milt Leong with Leong-Razzano and Associates, Inc. , the structural engineers, it is our understanding that the development will consist of a seven-story office building, two four-story office buildings and a five-level parking structure. Anticipated structural loads for the four buildings are as follows:

Building

4-Story Office Building A & B

5-Level Parking Garage

7-Story Office Building

Column

Interior Exterior Corner

Interior Exterior Corner

Interior Exterior Column

pproximate Dead Plus Live

Load (psf)

550 225 137

All buildings will probably be constructed at-grade. However, consideration is being given to including a basement beneath the seven-story building. In addition, at-grade parking will be provided for about 100 cars. If all buildings are constructed at-grade, then only minor grading will be required to dev€lop the site for the e11bject project. With a basement beneath the seven-story office building, about a 10-foot excavation would be required,

SCOPE

The scope of reconnaissance,

work performed in this investigation included a site subsurface exploration, laboratory testing, engineering


K893-1, Page 2, 07524

analyses of the field and laboratory data and the preparation of this report. The data obtained and the analyses performed were for the purpose of providing design and construction criteria for site earthwork, building foundations, slab-on-grade floors, retaining walls and pavements.

This report has been prepared for the exclusive use of Baker Sinclair, Inc, and Tai Associates/Architects and their consultants for specific application to the proposed Civic Center Office Park in accordance with generally accepted soil and foundation engineering practices. In the event that there are any changes in the nature, design or location of the buildings or if any future additions are planned, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and conclusions of this report modified or verified in writing.

SITE INVESTIGATION

A subsurface investigation was performed using a truck-mounted, 6-inch diameter continuous flight auger to investigate and sample the subsurface soils. Twelve exploratory borings were drilled on July 17, 18 and 24, 1985, to a maximum depth of 6H feet. The approximate locations of the borings are shown on the Site Plan, Figure 1. Logs of the borings and details regarding the field investigation are included in Appendix A, and the results of our laboratory tests are discussed in Appendix B,

A. Surface

The site is trapezoidal in shape and has maximum plan dimensions of approximately 550 by 600 feet. At the time of our field investigation, the site was vacant. The majority of the site was essentially level with a very gradual one percent slope from the west to the east. In the eastern portion of the site, the grades were slightly undulating. Billboards were located at the northern and western corners of the property. In addition, a few abandoned risers or possible wells related to past irrigation practices on the site were present and observed within the central portion of the site. Several pieces of concrete rubble were scattered near these abandoned risers. There was also an asphaltic concrete area along Walnut Avenue. The northern portion of the property line dropped approximately 10 feet in elevation to where an existing asphaltic concrete walkway was present. This difference in elevation gradually decreases towards the eastern half of the site. Vegetation consisted of a low growth of seasonal weeds over the entire site. Also, there were several large trees located at the north-northeast end of the site. The eastern property line is located adjacent to a depressed area with about a 10- to 15-foot high slope.

,. B. Subsurface

The surface soils encountered in our exploratory borings generally consist of stiff to very stiff silty clays and clayey sandy silts. These soils have low plasticities, low expansion potentials and an expansion index of 43 as determined by UBC Standard No. 29-2. Underlying these soils, we generally encountered loose to very dense silty and clayey sands and

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K893-1, Page 3, 07524

gravels which extended to the maximum depth explored of 6H feet. In Borings 8, 11 and 12, we encountered firm clays and silts to depths of approximately 11 to 31 feet. These soils are relatively weak and potentially compressible. Detailed descriptions of the soils encountered in each of the exploratory borings are presented in Appendix A.

The attached boring logs and related information depict subsurface conditions only at the specific locations shown on the Site Plan and on the particular date designated on the logs. Also, the passage of time may result in changes in the subsurface conditions due to environmental changes. The locations of the borings were approximately determined by pacing and should be considered accurate only to the degree implied by the method used.

C. Groundwater

Free groundwater was not encountered in any of the borings at the time of drilling. All borings were backfilled immediately after drilling. It should be noted that the borings may not have been left open for a sufficient period of time to establish equilibrium groundwater conditions. In addition, fluctuations in the groundwater level could occur due to change in seasons , variations in rainfall, and other factors.

D. Geology and Seismicity

The site is underlain by Quaternary unconsolidated to weakly consolidated Bedrock is probably at depths of greater

Age alluvial deposits including clay , silt, sand and gravel.

than 400 feet at the site.

The San Francisco Bay Area is located in one of the most seismically active regions in the United States. Significant earthquakes that have occurred in the Bay Area are believed to be associated with crustal movements along a system of subparallel fault zones that generally trend in a northwesterly direction. The site is located approximately 19 miles northeast and 7 miles southwest, respectively, of the active San Andreas and Calaveras fault zones.

In addition, the northeastern edge of the site is located within the Alquist-Priolo Special Study zone for the active Hayward fault zone. Woodward-Clyde Associates performed a detailed active fault investigation in 1970 of the Fremont Meadows project, which was located in the existing vacant field located at the southeast corner of the intersection of Civic Center Drive and Walnut Avenue. Both surface mapping and subsurface trench logging were performed and two active traces of the Hayward fault were identified at the site, an eastern and western trace. ,.

The western trace was found to be the most active of the two faults. It possessed well defined fault planes with a zone of active fault displacement ranging in width from 10 feet at the north to 78 feet at the south. Carbon-14 age dates indicated that the fault was located in the same general location for at least the last 2, 400 years with evidence of activity in the last 700 years. The active fault trace followed existing fault

l'l!ler-..,.1"110 data.In<.


K893-1, Page 4, 07524

contl'olled topogl'aphy and was genel'ally confined along the westel'n mal'gin of the adjacent tule pond, which is a sag pond pl'oduced by l'eCUl'l'ent fault displacement. The eastern fault trace was found to be less active than the western trace and appeared to die out with little potential for pl'opagation to the south. A groundwater barl'ier encountered along the fault zone was found to be about 60 to 100 feet higher on the east side of the fault. An earthquake along the Calaveras fault in 1970 may have coincidentally induced fault cl'eep along the Hayward fault in the Fremont Central Pal'k area, as was then reported by a City of Fremont employee.

The trenching results of the 1970 investigation indicated "that the west trace (of the fault) was found to be well-defined and was accurately located across the entire site. The east trace is well-defined by the topography along the eastern side of the Tysons Lagoon (tule pond) sag pond •.. " "Further southeast the east trace becomes less well-defined .... , and is suggested only by flexure of beds close to the surface, which in dictates the recency of activity." Bl'anch faults wet'e indicated as uncommon featul'es to the Haywal'd fault in the site vicinity.

Woodwal'd-Lundgren and Associates (fot'merly Woodward-Clyde Associates) performed another detailed geotechnical study for the proposed South County Hall of Justice in 1974 at the same property occupied by the Fremont Meadows project. The purpose of that investigation was to further evaluate surface rupture and the potential for ground deformation. The results of that study suggested that subsidiary faults were uncommon features in the Fremont ares and stated, "No evidence was found of subsidiary faults in any of the trenches, which suggests that subsidial'y faults are uncommon features in this area. In fact, no subsidiary faults have been identified during previous investigations along the Hayward fault from north of Irvington to near Union City. It is conceivable, but highly unlikely, that a subsidiary or splinter fault could form through the building sites (which were located west of the western active fault trace)". Subsidiary splinter faults were defined as branching from the main active fault trace up to one mile with displacements of several inches to one foot that decreased progressively away from the main fault. Subsidiary secondary faults were defined as branching from the main active fault trace up to 200 feet at an acute angle with displacement in inches and decreasing progressively along the length of the fault. Exploratory trenches located west of the western trace of the Hayward fault did not reveal the presence of fault displacement or significant ground deformation.

Earthquake intensities vary throughout the Bay Area, depending upon the magnitude of earthquake, the distance of the site from the causative fault, and the type of materials underlying the site, Neve~Jheless, the site will be subjected to at least one moderate to severe earthquake that will cause strong ground shaking. However, during such an earthquake, the hazard associated with sut'face ground rupture is considered to be low.

The summary of the 1974 Woodward-Lundgren and Associates report stated, "Based upon available data, the maximum ground deformation resulting from future fault movement will be confined to a relatively nal'row zone


K893-1, Page 5, 07524

closely adjoining the fault." Furthermore, "Drag and elastic rebound that may follow surface ground rupture can produce significant horizontal deformation. However, it is probably insignificant about 200 feet from the fault trace based upon past deformations along the San Andreas fault in 1906, and may be only 100 feet along the Hayward fault zone, which has a much shorter length than the San Andreas and therefore, is not capable of generating as great an earthquake". This interpretation was later supported by geologic evidence obtained in the Woodward-Clyde Consultant report of the Shinn property that was completed in 1976.

As presently planned, the furthest east edge of the parking structure and 7-story office building are set of the western trace of the Hayward fault trace by greater than 100 feet.

CONCLUSIONS AND RECOMMENDATIONS

From a soil and foundation engineering standpoint, it is our opinion that the site is suitable for the proposed Civic Center Office Park. However, all of the conclusions and recommendations presented in this report should be incorporated in the design and construction of the project to avoid possible soil and foundation problems. The primary considerations for foundation design at the site are 1) the relatively heavy column loads and 2) the relatively weak and potentially compressible soils underlying the site.

In order to provide adequate support and to minimize total and differential settlements, we recommend that the relatively heavier parking garage and Building "C" structures be supported on deep pile foundations that derive their support through end bearing resistance in the dense to very dense sands and gravels which exist at depths of 20 to 35 feet below existing grade.

Alternatively, if the seven-story Building "C" is constructed at existing grades, it can be supported on a mat foundation. If the seven-story Building "C" has a below-grade basement level, the building can be supported on conventional continuous and isolated spread footings suppol.'ted on a layer of engineered fill. We anticipate the following settlements for the footing supported (with basement) and mat suppol.'ted (no basement) 7-story office building:

Foundation Type

Interior Footing Exterior Footing Corner Footing

Mat Center Edge Corner

Approximate Dead Plus Live

Load (kip)

950 475 212

1715

Anticipated Settlement

(inches)

1/4 to 3/4 1/lr·to 1/2

1/4

1 to l l /2 1/2 to 3/4 1/4 to 1/2

___ ..........


K893-1, Page 6, 07524

The column loads of the proposed 4-story buildings could cause the slightly to moderately compressible silts and clays to consolidate. Long-term settlements were determined for the various column loads for the two four-story Buildings "A" and "B" supported on conventional footings. The calculated long-term settlements are based on an allowable dead plus live load bearing capacity of 3000 pounds per square foot. We should also note that the varied depths of these soils and difference between interior, exterior and corner column loads could cause varying total and differential settlements. We have calculated the following anticipated settlements for the proposed 4-story structures:

Location Total Loads Settlements (inches)

Buildings 0 A" and "Bu

Interior Column 550 kips l to 1 1/2 Exterior Column 225 kips l to 1 1/4 Corner Column 137 kips 3/4 to l

Based on the structural loads and the projected total settlements, differential settlements between adjacent footings of the 4-story Buildings "A" and "B" should be anticipated and addressed by the structural engineer in design and system selection. Our firm is available for consultations to discuss the impacts of the above settlements.

If the total and differential settlements of Buildings "A" and "B" supported on footings can not be tolerated, we recommend that the 4-story buildings be constructed on a pile foundation that derives its support through end-bearing resistance in the dense to very dense sands and gravels which exist at depths of 20 to 35 feet below e:icisting grade.

Detailed earthwork and foundation recommendations for use in design and construction of the project are presented below. We recommend that our firm be provided the opportunity for a general review of the final design and specifications in order that the ·earthwork and foundation recommendations may be properly intel'preted and implemented in the design and specifications. If our firm is not accorded the privilege of making this recommended review, we can assume no responsibility for misinterpretation of our recommendations.

A, Earthwork

1 . Clearing and Site Prepal'ation

The site should be cleared of all obstructions including billboards, any underground irrigation lines or utilities, risers, .·· asphaltic concrete, concl'ete rubble, designated trees and associated roots and debris. Holes resulting from the removal of underground obstructions that extend below the proposed finish grade should be cleared and backfilled with suitable material compacted to the requirements given below under Item A. 7, "Compaction". We recommend that the backfilling operations for any excavations to remove deleterious material be carried out under the observation of the soil engineer, so that these excavations will be properly backfilled.

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K893-1, Page 7 ,7.'07524

After clearing, the portions of the site containing surface vegetp.tion or organic laden topsoil should be stripped to an appropriate depth to,tl'emove these materials. At the time of our field investigation, we estimated that a stripping depth of approximately 3 inches would be required. The ,amount of actual stripping should be determined in the field by the soil eI).gineer at the time of construction. The cleared and stripped materials should be removed from the site or stockpiled for later use in landscaping, if desired.

2. Well Removal and Capping

Any existing wells must be removed and capped in accordance with the requirements of the Alameda County Health Department.

3 , Engineered Fill Layer

If conventional footings are used to support the seven-story Building "C" with a basement level or a mat foundation at-grade, we recommend that the loose and relatively weak soils be removed and reworked where they are encountered under the footings or mat. The reworking should extend to a depth of 3 and 5 feet below the footings or mat, respectively, as shown on Figures 2 and 3. However, the actual lateral extent of reworking should be determined in the field by the soil engineer at the ~me of construction.

The removed materials can be temporarily stockpiled for later use as fill provided they meet the requirements given below under Item A. 6, "Mat11rial for Fill". The temporarily stockpiled soils from the excavation can then be compacted in accordance with the requirements given below under .Item A. 7, "Compaction". Construction slopes required during the excavation of the surface materials should be the responsibility of the contractor performing the work.

4. Temporary Construction Slopes

We recommend that temporary construction slopes conform to the OSHA's "Guidelines for Excavations and Temporary Sloping". However, we also recommend that all vehicles be kept at least 10 feet away from the top of temporary slopes, that temporary slopes be protected from excessive drying and/or saturation during construction and that we have the opportunity to observe all excavated slopes for conformance with the anticipated soil conditions.

5. Sub grade Preparation

After the site has been properly cleared and strip pep \'.fmd any necessary excavations made, the exposed soils in those areas to.- receive structural fill, slabs-on-grade or pavements should be scarified' to a depth .of 6 inches, moisture conditioned to slightly above optimum water content and compacted to the requirements for structural fill. +

6. Material for Fill li'lli

Ali on-site soils below the stripped layer and having an organic content of

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K893-l, Page 8, 07524

less than 3 percent by volume can be used as fill. However, all fill placed at the site including on-site soils should not contain rocks or lumps larger than 6 inches in greatest dimension with not more than 15 percent larger than 2. 5 inches. In addition, any required import fill should be predominantly granular with a plasticity index of 12 or less.

7. Compaction

All structural fill less than 5 feet thick should be compacted to at least 90 percent relative compaction as determined by ASTM Test Designation D1557-78, except for the upper 6 inches of subgrade soils under pavements which should be compacted to at least 95 percent relative compaction. Structural fill or wall backfill greater than 5 feet deep and the engineered fill below footings or mat should be entirely compacted to at least 95 percent relative compaction. Fill material should be spread and compacted in lifts not exceeding 8 inches in uncompacted thickness.

8. Trench Backfill

Pipeline trenches should be backfilled with fill placed in lifts of approximately 8 inches in uncompacted thickness. However, thicker lifts may be used provided the method of compaction is approved by the soil engineer and the required minimum degree of compaction is achieved. If on-site soil is used, the material should be compacted to at least 85 percent relative compaction by mechanical means only. Imported sand can also be used for backfilling trenches provided it is compacted to at least 90 percent relative compaction. If imported sand is used, sufficient water should be added during the trench backfilling operations to prevent the soil from "bulking" during compaction. In slab and pavement areas, the upper 3 feet of trench backfill should be compacted to at least 90 percent relative compaction for on-site soils, and 95 percent where imported sand backfill is used. In addition, the upper 6 inches of all trench backfill in pavement areas should be compacted to at least 95 percent relative compaction.

9. Drainage

Positive surface gradients should be provided adjacent to the buildings so as to direct surface water away from foundations and slabs toward suitable discharge facilities. Ponding of surface water should not be allowed adjacent to the structures or on pavements.

10, Construction During Wet Weather Conditions

If construction proceeds during or shortly after wet weather conditions, the moisture content of the on-site soils may be appreciably above optimum. Consequently, sub grade preparation, placement and/ or reworking of on-site soil as engineered fill may not be possible. Alternative wet weather construction recommendations will be provided by the soil engineer in the field at the time of construction, if appropriate.

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K893-l, Page 9, 07524

11. Guide Specifications

All earthwork should be performed in accordance with the Guide Specifications - Site Earthwork presented in Appendix C. It should be pointed out, however, that these specifications are only general in nature and the actual job specifications should also incorporate all requirements contained in this report.

B. Foundations

1. Footings

If a below grade basement level is incorporated into the design of Building "C" and if the anticipated total and differential settlements are within tolerable limits for Buildings "A" and "B", these buildings can be supported on conventional continuous and isolated spread footings bearing on either undisturbed or reworked natural soils or compacted fills. For the seven-story building to be supported on spread footings, the footings should be underlain by a layer of engineered fill as discussed previously under Item A. 3, "Engineered Fill Layer". All footings should be founded at least 36 and 24 inches for the seven-story and four-story buildings, respectively, below lowest adjacent finished grade. In addition, footings located adjacent to other footings or utility trenches should have their bearing surfaces situated below an imaginary 1. 5 horizontal to 1 vertical plane projected upward from the bottom edge of the adjacent footings or utility trench.

At the above depths, the footings can be designed for an allowable bearing pressure of 2000 pounds per square foot due to dead loads, 3000 pounds per square foot due to dead plus live loads and 4000 pounds per square foot for all loads including wind or seismic. These allowable bearing pressures are net values; therefore, the weight of the footing can be neglected for design purposes.

Any visible cracks in the bottoms of the footing excavations should be closed by wetting prior to construction of the foundations. To assure that footings are founded on appropriate material, we recommend that we observe the footing excavations prior to placing reinforcing steel or concrete.

2. a.

We recommend that the parking garage be supported on a pile foundation system. If the anticipated total and differential ,.settlements for the seven-story Building "C" supported at-grade on a mat foundation, or supported below grade on conventional footings cannot be tolerated, we recommend that this building also be supported on a pile foundation. In addition, if the anticipated total and differential settlements for footing supported four-story Buildings "A" and "B" can not be tolerated, we recommend that these buildings also be supported on a pile foundation system. The pile foundation should derive its load bearing capacity from

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K893-1, Page 10, 07524

end-bearing in the dense to very dense sand and gravel layer which underlies the site at depths of 20 to 35 feet below the existing ground surface. For estimating purposes, we recommend that pile tip depth across the site be assumed to be 35 feet below existing grade, However, the actual lengths should be determined from the indicator pile program discussed in the next section.

We recommend that 12- or 14-inch square p:t'ecast-prestressed conc:t'ete piles be used. The piles should extend a minimum of 5 feet into the bearing layer. The 12- and 14-inch square piles can be designed for an allowable dead plus live load capacity of 85 and 100 kips, respectively, These loads can be increased by one-third for all loads including wind and seismic. An allowable uplift capacity for 12- and 14-inch square piles will be 25 and 30 kips, respectively. In addition, the piles should have a minimum center-to-center spacing of 2. 5 times the pile width.

Total and differential settlements of the piles extended to this layer supporting the dead plus live loads recommend above would be within tolerable limits for the proposed structures.

It should be noted that the intermittent and non-continuous lenses of medium dense to dense sands and gravels encountered at various depths across the site could be very difficult to drive through. Therefore, for ease of construction in these areas as determined by the indicator pile p:t'ogram and to achieve the approximate required tip elevations, we recommend pre-drilling to within 5 feet of tip elevation. The diameter of the predrilled hole should not exceed the width of the pile. Because of the possibility of caving sands and gravels, we recommend that predrilling be allowed only with a continuous flight auger.

b, Indicator Piles

In order to verify the depth of the underlying dense to very dense sands and gravels across the site and to establish production pile lengths, we recommend that at least 12 indicator piles be driven in each building area at the start of construction. The indicator piles should be driven at various locations across the site, including near our exploratory boring locations. Additional indicator piles should be driven at locations approved by our engineer in the field. In order to provide adequate information, the indicator piles should be a minimum of 5 feet longer than their anticipated length (tip of indicator piles to be 40 feet below existing grade) and should be driven with the same equipment that will be used during production driving, The indicator piles may be driven at production pile locations.

,.

c. Pile Driving Criteria and Installation

All piles should be driven at least 5 feet into the gravels which underlie the site at depths of approximately 20 to 35 feet below existing ground surface or to such shorter depths as determined by the indicator piles, in order to develop adequate end-bearing capacities. Any piles that terminate shorter than their anticipated lengths will be evaluated on an

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K893-1, Page 11, 07524

individual basis. We should note, however, that in no case should driving be terminated without the approval of the soil engineer.

The pile driving hammer should be a minimum rated energy of 30, 000 foot/pounds for prestressed concrete piles. It is possible for a very large hammer to cause damage to the particular pile it is driving; therefore, we recommend that our office and the structural engineer approve the hammer type and capacity selected by the contractor. ln addition, the method of handling and picking up of the piles should be established by the pile driving contractor and should be approved by both the structural engineer and the soil engineer prior to construction.

d. Specification and Construction Observation

As an aid in developing the pile specifications for this project, guide specifications for pile foundations are included in Appendix D. We recommend that our office review the final foundation plans and specifications to assure that the recommendations presented in this report have been properly incorporated into the contract documents. To assure that piles are .extended to adequate depths and that they have encountered sufficient resistance to develop the required supporting capacities, we recommend that our firm observe the driving of the piles installed at the site.

3. Structural Mat Foundation

As an alternative to the deep pile foundation, the seven-story Building "C" can be supported on a structural mat foundation at-grade if the anticipated settlements are within tolerable limits. We recommend that the structural mat foundation be constructed on a 6-inch levelling course of Class 2 aggregate baserock placed over the required engineered fill layer. Recommendations for the engineered fill layer were presented previously under Item A. 3. The slab can be designed for net allowable bearing pressures of 2000 pounds per square foot for combined dead plus live loads with a one-third increase fol' all loads including wind ol' seismic. In calculating resultant pressures, the weight of the excavated soil can be deducted; a soil density of 120 pounds per cubic foot can be assumed for design purposes. In addition, a modulus of subgl'ade reaction of 150 pounds per square inch pel' inch can be used for the design of the mat.

4. Interior Slabs a. Office Area At-Grade

Interior office slabs-on-grade can be supported dil'ectly on the propel'ly prepared sub grade. Sub grade prepal'ation was discussed previously under Item A. 5. Prior to final constl'uction of the slab, the subgrade surface should be pl'oof-rolled to provide a smooth, firm surface fol' slab support. Slab reinforcing should be provided in accordance with the anticipated use and loading of the slab.

In areas where floor wetness would be undesirable, a moistul'e bal'rier and/or capillary break should be provided between the slab and subgrade.

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K893-1, Page 12, 07524

If a moisture barrier is required, we recommend it consist of 4 inches of free draining gravel covered with an impermeable membrane placed between the sub grade soil and the slab. The membrane should be covered with 2 inches of sand to protect it during construction, and the sand should be lightly moistened just prior to placing the concrete.

b. Office Area Below Grade

If the 7-story structure has a basement, we recommend the slab be constructed on a moisture barrier to avoid floor wetness. The moisture barrier should consist of 4 inches of free draining gravel covered with an impermeable membrane. The membrane should e covered with 2 inches of sand to protect it during construction, and the sand should be lightly moistened just prior to placing the concrete.

The moisture barrier should be placed on a properly prepared subgrade. Subgrade preparation was discussed previously under Item A. 5. Prior to final construction of the slab, the subgrade surface should be proof-rolled to provide a smooth, firm surface for slab support. Slab reinforcing should be provided in accordance with the anticipated use and loading of the slab.

To avoid trapping water beneath the slab, we recommend that a perforated collector pipe, imbedded in the Claes 2 aggregate base, be placed along the centerline of the slab. This collector pipe should drain the collected water to an appropriate discharge facility. In addition, the slab should be moisture proofed.

c. Garage Area At-Grade

The garage slab should be supported on a 6-inch levelling course of Class 2 Aggregate Base. The aggregate should be placed on a properly prepared subgrade. Subgrade preparation was discussed previously under Item A, 5. Prior to final construction of the slab, the sub grade surface should be proof-rolled to provide a smooth, firm surface for slab support. slab reinforcing should be provided in accordance with the anticipated use and loading of the slab.

In areas where floor wetness would be undesirable, a moisture barrier and/or capillary break should be provided between the slab and subgrade. Recommendations for the moisture barrier and/ or capillary break were provided previously under ltem B. 4. a. The moisture barrier or capillary break can be used in lieu of the required 6-inch levelling coarse.

5. Basement Walls ,.

If a basement level is incorporated into the design of the seven-story Building "C", the below grade walls must be designed to resist both lateral earth pressures and any additional lateral loads caused by surcharge loads on the adjoining ground surface.

We recommend that unrestrained walls with a level backfill be designed to

___ , ..........

I I I I I I I I I I I

I I I I I I I

K893-1, Page 13, 07524

resist an equivalent fluid pressure of 35 pounds per cubic foot, We recommend that restrained walls be designed to l'esist an equivslent fluid pressul'e of 35 pounds pel' cubic foot plus an additional unifol'm latel'al pressure of 7H pounds pel' squal'e foot where H " height of backfill above the top of the wall footing in feet, In addition, walls that have a backfill that slopes upward away from the wall should be designed for an additional equivalent fluid pl'essure of 1 pound pel' cubic foot for every 2 degrees of slope inclination.

Whel'ever walls will be subjected to sul'chal'ge loads, they should be designed for an additional uniform latel'al pressure equal to one-thil'd Ol' one-half the anticipated surchal'ge load depending on whethel' the wall is unrestl'ained Ol' restrained.

The pl'eceding pressures assume sufficient drainage behind the walls to prevent the build-up of hydl'ostatic pressures from sul'face water infiltration and/ol' a rise in. the gl'oundwater level. Adequate drainage may be provided by means of eithel' weep holes with permeable material installed behind the walls or by means of a system of subdrains. Fol' the subdl'ain system, the top of the perfol'ated pipe should be below the bottom of the adjacent floor slab.

Backfill less than 5 feet deep which is placed behind the walls should be compacted to at least 90 percent relative compaction using light compaction equipment. Backfill greater than 5 feet deep should be entil'ely compacted to at least 95 pel'cent relative compaction. If heavy compaction equipment is used, the walls should be appl'opriately designed for the heavy equipment and/ol' temporarily braced.

Basement walls should be suppol'ted on deep pile foundations designed in accordance with the recommendations presented previously under Item B .1, "Footings" or B.2, "End Bearing Piles". Lateral load resistance for the walls can be developed in accol'dance with the recommendations pl'esented below under Item B, 6, "Lateral Loads".

6. Latel'al Loads a. Footing and Mat

Lateral load resistance for the buildings and basement walls can be developed in friction between the foundation bottom and the supporting sub grade. A friction coefficient of 0. 35 are considered applicable for the at-grade structure and structure with basement, respectively. As an alternative, a passive resistance equal to an equivalent fluid weighing 300 and 350 pounds per cubic foot acting against the foundations may be used for the at-grade structure and structure with basem1t11t, respectively. If the foundations are poured neat against the soil, friction and passive resistance can be used in combination.

b. Pile

Passive resistance can be developed against the grade beam and pile cap using an equivalent fluid weighing 300 pounds per cubic foot. Lateral load

_...._. .... ,. ... bl<.


K893-1, Page 14, 07524

resistance can be developed against the pile shaft. We recommend a passive resistance equal to an equivalent fluid weighing 600 pounds per cubic foot acting against the upper 10 feet of the projected area of the individual pile shafts be used.

C. Characteristic Site Period

To assist in the seismic design of the proposed structures, we have analyzed the materials underlying the site and determined a range for the characteristic site period. Calculation of the characteristic site period was performed in accordance with the recommendations of the 1982 Edition of the Uniform Building Code. Our calculations indicate a site period (T ) ranging from 1 . 0 to 1. 6 seconds. We recommend that an average value ~f 1 . 3 seconds be used in design.

D. Pavements

One "R" (resistance) value test was performed on a representative bulk sample of the surface materials at the site. The results of this test are presented in Appendix B and indicate an "R" value of 12. Combining this information with an appropriate traffic index for the proposed automobile and heavy truck parking and access areas, we have developed the following alternative pavement sections using Procedure 301-F of the State of California Department of Public Works, Division of Highways. We have included pavement designs for pavement lives of 1 to 5 years, 6 to 10 years and 11 to 20 years.

RECOMMENDED PAVEMENT DESIGN ALTERNATIVES

Pavement ComEonents Anticipated Asphaltic Aggregate Total

Pavement Concrete Base Class 2 Thickness Location Life (years) (inches) (inches) (inches)

Automobile Parking 11-20 2.0 8.0 10.0 Areas 6-10 2.0 7.0 9.0

(T. I. • 4.0 for 1-5 2.0 6.0 8.0 20-year life)

Automobile and Light to 11-20 2.5 12.0 14.5 Moderate Truck Access 6-10 2.5 11.0 13.S (T. I. ~ 5.S for 1-5 2.5 10.0 12.S 20-year life)

,. The traffic indices used in our pavement designs are considered reasonable values for the proposed development and should provide the indicated pavement lives with only a normal amount of flexible maintenance. Selection of the design traffic parameters, however, was based on engineering judgement and not on an equivalent wheel load analysis developed from a traffic study or furnished to us.

- _ _. -11•n1&.• hlL


K893-1, Page 15, 07524

Asphaltic concrete, aggregate base and preparation of the subgrade should conform to and be placed in accordance with the Guide Specifications -Asphalt Paving presented in Appendix E.

In areas where the pavements will abut planted areas, the pavement baserock layer should be protected against saturation from water in the planters. This can be accomplished by extending the concrete curbs to the bottom of the baserock layer, forming a cut-off wall between the planter and the pavement section.

E. Construction Observation

The analysis and recommendations submitted in this report are based in part upon the data obtained from the twelve soil borings. The nature and extent of variations between the borings may not become evident until construction. If variations then become apparent, it will be necessary to re-evaluate the recommendations of this report.

We recommend that our firm be retained to provide soil engineering services during the excavation and foundation construction phases of the work. This is to observe compliance with the design concepts, specifications and recommendations and to allow design changes in the event that subsurface conditions differ from that anticipated prior to the start of construction.

* • • * * * * * • • • * * * • • •

................ , ..........


/ /

) I I I

"' " ... z c ~

' •

' '

........

" I j i l I • I ' I

i !

--·--· .. -- ----------------·------------/

~EGEND

EB-3 • APProx1mate Location of Exploratory Baring-

PETER KALDVEER

AND ASSOCIATES, INC.

Conaultlng ileotechnlcal Engineers

,.

SITE PLAN

CIVIC CENTER OFFICE PARK fremant, California

100

PflOJECT NO. DATE 1-.....:..::.:::::::..:.....:..:::;....4 __ _;;....;... __ -( Figure '. K 893- I

{i9Q•I

- - -Compacted lmprevious Materia.ts

A. pp .-o x~rnate Fi nls he<l G n:1d e-

C.·:i ns t r uctktn S lo P"'"H 1..:;; •on si bilit y or c.:~,nl r:\ctor

R ewo.- k-ed On-Si SoH and lo r 1 m port-ed Fill•

- -

'

- - -E xtedo r F ootin CJ

'n"a.ter Proof1r:11}

Dralri.rock

as.eme-n t Wall

6-1 nc hi D•aimeter Pe rior ote-0 Pipe 'ti it h Per fo rallon Down ~Top of P lpe S 00-uld Be El elo•,o,• Top of SJ ab l

R eoom r,acuon

N'...'t~ .:... ta.in rOck should -conform ~o Stat-e of California D !vision· of Hfqhw ays, Cl ass 2 Permea:b le Mate-rial a-s follows:

- - - - - - - - - -Sec~111il !'L•D

t::l.c'!i!

4-Inch Ola.meter Perforated Pipe to Dissi pa.le- Tr a.p ped ~\' nte r (p-erforation dowI1)

B a.r rier or C apl L!a.ry B r eak

B a.se111e nt S Lab

Const n.Jction Slop irRes pons Lhtll ty of Contractor

. ' -

He.-.·o rkerl Q n - Sile Soll a1Ld lo• Imported [ill"'"

I nte rlor r-001l nn

-. -' :. . . . '.·_ ~ -~ . . . . · . . :.· .. _-.;. -- .,, -;.'.:.:_~:

R ecorn Pa.ction

"'T be- soil!': should be ny...-o r k ed t-0 r f! l i'lti .._..~ .;:::rnn fl <'Ir:' io 11 of 95 u (>C-Ce!l t • Sieve Slze

l" 314 11

318" NO: 4 No. 8 No. JO No. SO No. 200

Percent Pas.sing

lOO 90- lOO 40- .;.l)'l

2S-40 18- ll S-15 0-7 0-3

PETER KALDYEER AND ASSDCIATES, INC.

~DIC001t.1lr.:ia

REWORKIN('. RE'1UIRED roR 7-STORY i3UILDING WITH F3.ASEt1E-NT ON FOOTINCi

CIVIC CENTER OFFICE PARK Fremont, Californla

-------------------

Proposed Seven Story Building

Construction Slo Responsibility of Contractor

Mat Foundation

F.e,,.rorked On-Site Soil and /or Imported Fill Compacted*

SCHEMATIC ONLY

NOT TO SCALE

*Engineered fill below building to be compacted to 95 percent relative comp action.

PETER KALDVEER

AND ASSOC I A TES, INC.

Geor.chniclll Cmiwlran ts

Finished Grade

Construction Slope Responsibility of Contractor

~carify, Moisture Condition and Compact*

EQUIRED REW RKING B NEATH MAT FOUNDATION FOR 7-STORY BUILDING

CIVIC CENTER OFFICE PARK Fremont, California

K893-l

PROJECT NO~ DA TE t-------;----:--:---i Figure 3

eptember 1985


K893-1, 07524a, 1

APPENDIX A - FIELD INVESTIGATION

The field investigation consisted of a surface reconnaissance and a subsurface exploration program using a truck-mounted, continuous flight auger. Twelve 6-inch diameter exploratory borings were drilled on July 17, 18 and 24, 1985, to a maximum depth of 61! feet. The locations of the exploratory borings are shown on the Site Plan, Figure 1. The soils encountered in the borings were continuously logged in the field by our representative. The soils are described in accordance with the Unified Soil Classification System (ASTM D-2487), The logs of the borings as well as a key for the classification of the soil (Figure A-1) are included as part of this appendix.

Representative soil samples were obtained from the exploratory borings at selected depths appropriate to the soil investigation. Undisturbed samples were obtained using a 3-inch 0, D, Modified California sampler and disturbed samples were obtained using the 2-inch 0. D. split spoon sampler. All samples were transmitted to our laboratory for evaluation and appropriate testing. Both sampler types are indicated in the "Sampler" column of the boring logs as designated below:

[D Split Spoon

~ Modified California

Resistance blow counts were obtained with the samplers by dropping a 140-pound hammer through a 30-inch free fall. The sampler was driven 18 inches, or a shorter distance where hard resistance was encountered, and the number of blows were recorded for .each 6 inches of penetration. The blows per foot recorded on the boring logs represent the accumulated number of blows that were required to drive the last 12 inches, or the number of inches indicated where hard resistance was encountered. When the split spoon sampler was used, these blow counts are the standard penetration resistance values. However, due to the larger diameter of the Modified California sampler, the blow counts recorded for this sampler are not standard penetration resistance values. Consequently, these values are followed by an asterisk (*) on the boring logs. In order to convert these values to standard penetration resistance values, the indicated blow counts should be multiplied by a factor of 0, 56.

The attached boring logs and related information show our interpretation of the subsurface conditions at the dates and locations indicated, and it is not warranted that they are representative of subsurface conditions at other locations and times. ,.

---- .........

I I I I I I I I I I I I I I I I • --

I

PRIMARY DIVISIONS GROUP SE~ DIVISIONS SYllllBOl

GRAVELS CLEAN GW Well graded gravels. grcrYel-Mnd mi•tures. little or no --' GRAVELS firtn, :!:

U) a: 0 MORE THAN HALF (LESS THAN Pootty graded grawts Ot gr~l-sand nii.11tures. little Ot _, .. 0 5% FINES) GP no fines. 5 ~ " OF COARSE

U)

... 2 FRACTION IS GRAVEL GM Silty gra;;els. gravel-5and-511i mns:iures. non-plastic fine&.

8 .. LARGER THAN WITH ·oz N

~ ..... <ii NO. 4 SIEVE FINES Ge Clevey gr8vels, gravel-sand-clay mixturlt$, plastic fines

~ i!: .. CLEAN > SANDS SW Wall graded sands. gravelly saods. lit1l111 or no tine1 . a: .. SANOS

! ~ .. <ii

MORE THAN HALF (LESS Tl1AN i!: ~ OF COARSE 5% FINES l SP Poorly graded sands Of gravelly sands. little or no finft..

--' .. !1l FRACTION IS SANDS SM Silty sands, sand-sih mi,i;turn. non-plastic fines. 1lj

:;; SMALLER THAN WITH NO. 4 SIEVE FINES SC Clayey undi!'i, sand-cl"¥ mixturn. p4•stN:: finn, ..

SILTS AND CLAYS ML lnor= silts 11nd very fine unds. rockJ!!,..°;°'· 1ilti or ~ ~~

N c fine sands Of e~ silts. with ~ t ptnt" ·1v. <ii

iii ~i ~ LIQUID LIMIT IS CL l~c cl•Y5 of low to medium plilsttcity. grav91y

c . undy clays, silty cl•ys. ie.,,. c:ley5 . .. LESS THAN 50% c ii> DL Otganic: 5il1s and organic $ih:y clays of low pl•5ticity.

~ ~

!1l 0

~ 0

~ic sflt5. miCIC90US or diltomKeOU• fine sandy or --' .... SILTS ANO CLAYS MH :!: . s1tty SO•t5. elastic silts.

§ a: !! "' LIOUIO LIMIT 15 CH Inorganic clay5 of high plasticity. f.at clays.

!!! i ~ GREATER THAN 50% u:: I- OH Or91nic c:i•'VS of metH-.im to h91 plasOeity, OfgmiK: .-us.

HIGHLY ORGANIC SOILS Pt Pe.at and othef highly organic soil$.

DEFINITION OF TERMS

U.S. STANOARD SERIES SIEVE CLEAR SQUARE SIEVE OPENINGS 200 4D 10 4 3/1111 311 12•

SAND GRAVEL SILTS ANO CLAYS

I I COARSE COBBLES BOULDERS

FINE MEDIUM COARSE FINE ..

GRAIN SIZES

SANDS AND GRAVELS BLOWS/FOOT t SILTS AND CLAYS STRENGTHt Bl.OYVS/FOOT 1

VERY LOOSE 0 - 4 VERY SOFT 0 - 1/4 0 - 2

LOOSE 4 -lD SOFT 114 - 1/'2 2 - 4 FIRM 112 - 1 4 - 8

MEDIUM DENSE 10 -JO STIFF 1 - 2 8 - 16 DENSE JO - 50 VERY STIFF 2 - 4 16 - 32

VERY DENSE CNER 50 HARO OVER 4 QVl'R 32

RELATIVE DENSITY CONSISTENCY tNumbM of bfows of 140 pound hammer falling 30 incl"les to driw a 2 inch 0.0. Cl-3./8 ind\ 1,0.l

"'Iii _,in CASTM D-1~1:161. flktcontined compr1tM1ive strength in tons/sq. ft. at· determined by labor•tory ••ting Ot ...-womated

by the st.nd•rd penetration test CASTM 0-1588). poeket penetrometer. to~y•ne. °' visual ob$ervation .

KEY TO EXPLORATORY BORING LOGS

PETER KALDVEER Urtified Soil Classification Svstem CASTM D-2487)

AND ASSOCIATES, INC. GI VIG GENTER OFfIGE PARK

Fremont, California Geotechnlclll Consult11nts

PROJECT NO. DATE

September 1985 Figure A-1

K893- l


OAILL Rl<Continuous Flight Auger SURFAce ELEVATION -- LOGGED BY DYR

OEPTH TO GROUNOWATetlJot Established BORING OIAMETEA 6 Inches OATE OFULLEO 7/17/85

~~= ,..

e~= DESCRIPTION ANO CLASSIFICATION ~ • ....

S.c:~ .. - ;; z" -OEPTH "' .. - - ~ 0 -~ ~-" .... z z-:;: I.I.I z;:; • - .. 'l " "' ....

lfl!ITI 2 Q~ f,,) a:; Ii .:ti;

Sv 1~ • II.I cii 0 11:2 ". -oeSCRIPTION ANO REMARKS COLOR CONSIST. " z .. - " ,.._

z 2 ti TYPE ~c!! " ~ " c " CLAY, silty Jrown stiff .::L -_l_ 14 11

I - l I - -

-SILT, very clayey, trace of sand 1ark stiff ML- - -Jrown CL .. 5

=~ - 21* 15 107 1.9

-SAND (fine-grained), with some medium SC an clay crnd silt dense - ..

SAND (fine-to coarse-grained) , ~an- loose SM -io gravel. trace of fines grey

::t - 14* 8 102 I

SAND (fine-grained) , with some tan loose ;:,IVJ- 9 gravels (fine-grained), trace of SP -silt - -Passing #200 Sieve = 34% - 15

=~ - 15* 5 • - -(grading with more silt and less SM -gravels) .. -Passing #200 Sieve = 11% medium ...-20

dense u_ 11 .. -(6" lense of gravels)

.. -.. -.. -SW- -25 -(grading gravelly) SM I 26 - -- -

- -- -(grading with less gravels) -30

-j_ 17 6 .. - -

GRAVEL (fine-to coarse-grained) , grey- dense GW-- -sandy, trace of fines tan GM _ -(interbedded with lenses of sand - 35 -I with gravels) - - 41

- -- .--- --40 .. -·· '

33

EXPLORATORY BORING LOG

Peter Kaldveer •nd Associates CIVIC CENTER OFFICE PARK Fremont, California

G.o-.hnial Conwl,_a PROJECT NO. OATE BO FUNG K893- I Seotember NO. 1

1985


DRILLRl<Continuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

DEPTH TO GROUNOWATEFN ot Established BORING DIAMETER 6 Inches DATE DRILLED 7117/85

DESCRIPTION ANO CLASSIFICATION z 1.1.1""':" i!: 0 w S!~[ w ~ <

~ a:: ;; .z r;, ~ OEPTH ~ ~ "'·-- "'z z- - en (j ~ - "' .. " w l'l ""- w z ....

~ '"w ! ~ .... .,., ffEETl ~ .. "'~ " .. 0 "- ~ 1% ~

DESCIUPTION AND REMARl<S COLOR CONSIST. SOIL < ~~...I ~z >-- " .... TYPE " ~ ~ !. c "' !'; 0 " u

" " GKAv .t.L (tine to coarse-grained), grey dense c1IVJ

41 -sandy, with traces of silt brown - I ( contln ued J - " I - -- -

.... ~5 -- -- -

-- T 49

bottom ot boring " :,u J:'eet 50 - -

- -Notes; - -1. The stratification lines re pre- - -sent the approximate boundar-ies - 55 -between soll types and the tran- - -sltlons may be gradual. - -2. For an explanation of penetra- - -tion resistance values marked -with an asterisk ( *) ' see first -60-page, Appendix A. .... -- -- -- -

.... 65 -- -

.... -

.... -

.... --70-- -.... -- -.... -.... 75 -.... -- -- -.... , ...... --so-

EXPLORATORY BORING LOG PETER KALDVEER

AND ASSOCIATES, INC. CIVIC CENTER OFFICE PARK Fremont, California

G«>Nehnial Consu/,.,a PROJECT NO. DATE BORING K893-l Seotember 1985 NO. 1


CAILLFUG(;ontinuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

CEPTH TO GROUNOWATE!Not Established BORING OIAl\IETER 6 Inches DATE ORILLEC 7117/85

§ ... ., ~ ,. o~-DESCRIPTION ANO CLASSIFICATION • ...

"' i: :! :: o:;;; ;;; ... - -z"' -DEPTH - <<' ~z z- ;:;:;rill~

it ~~~ -"' <" .... z: I.ii •/l

Sull <FEUI 2 ... ;; i:z 0 le <.:!~ .... II'. < ~§~-CH~IPTION ANO REMARKS COLOR CONSIST. TYPE .. z .. ~ ,. -:res ~ "' Q

SILT, clayey, trace of sand dark stiff ML

~* brown - 1 13 - 28* 13 - ~ - -

.... 5 ~~ brown ... 20* 15

- -(interbedded with very silty clay) ... .•

-(lense with some sand) firm -io ... -f 13* 16 103 0.9

- - 11 SAND (fine-grained) , with some brown medium SM - -silt dense - -Passing #200 Sieve = 12%

- 15 -... -IT 10

' - -(grading to traces of silt) SM-- -SP - -

-20

(grading with traces of coarse- - -u 16 4

grained sand and pea gravel) - -SM· - -SW - -

dense - 2.5 -I - - 32 (grading gravelly) - -- -(lense of clayey silt) medium - -

-3.0 dense J_ 20 14 - -- -... -- -- 35 -[ 25 - -- -

GRAVEL (fine-to coarse-graineoJ, grey- very liVV - .~

sandy, trace of fines brown dense GM. -Passing #200 Sieve = 5% -40

67


Peter Kaldveer and Associates CIVIC CENTER OFFICE PARK Fremont, California

G.o-iaJ Cot>w/.,<$ PROJl!CT HO. DATE BORING

K893-l September 1965 HO. 2

I I I I

' I I I I I I I I I I I I I I

ORILLRIG Continuous Flight Auger SURFACE ELEVATION"- LOGGED BY DYR

DEPTH TO GROUNOWA TEFi'J ot Established BORING OIAMETER 6 Inches DATE DAILLEO 7117/85

;:- wr-: i:. QW

DESCRIPTION ANO CLASSIFICATION 0 " ... w >' = ~ ;;i:~ "' ;: ;;; z ;;:; I-

DEPTH w < < - "'z z- i;i; ~ i ~ ~ "' >- "' >- w w ..

!FEETl ~ >- "'~ < >- QU ~a= \J,j ~ SOIL < ~w; j: z ,. e (,.\ 0.. c:: ~

OESCl'llPTION ANO REMARKS COLOR CONSIST. TYPE "' ~~~ c "' z ~ti;

" Q ~"

GRAVEL (fine-to coarse-grained) , brown· ve>y GW-41 -sandy, tr-ace of fines (continued) dense GM -grey

- -

- -(inter-bedded lenses of gravelly - -sand) .... 45 -

- --- .. --so

-LL 69 4 -- -- -- -- 55 -- -

Bottom ot ~orlng "' bl 1-'eet - -- -

Notes; -60-

1. The stratification lines repre- - -sent the approximate boundaries - -between soil types and the tran- - -sitions may be gradual. - -2. For an explanation of penetra- - 65 -tion resistance values marked - -with an asterisk ( *) ' see first - -page, Appendix A. - -

- --70-- -- -- -- -- 75 -- -- -- -- ,. --so-

.. -


CIVIC CENTER OFFICE PARK AND ASSOCIATES, INC. F•emont, Califo•nia

GM>tfdtnit:al Conwlr.ntt PROJECT NO. DATE BORING

KB.93-1 :::entember 1985 NO 2


DAILL AIG Continuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

DEPTH TO GAOUNOWATElfll ot E sta.b!is hed SORING DIA ... ETEFI 6 Inches DA TE DRILLED 7/18/85

~~= ,,.

Q ..

DESCRIPTION ANO CLASSIFICATION c . ... '"> r = z1.1. c- '" z,:; -

DEPTH .. ~~~ .. - z- ;:. ~ ~::.

~ ~· ..... 2: II.I z ~ ~ -" .. ..

" :t r.:i a:; ... -t:

OESCllll'TIOH ANO REMARKS CONSIST. Su1L !Flli.Tl .. .. ;; ll::i ~~~~ COLOR TYPE " "'"ii ~ ,. -~"'- u "' Q

CLAY, very silt :l a.rk very c.;L

~rr stiff .. l 18 9 t>rown , ..

SILT, with clay, trace of sand Drown very ML ' stiff

~ -I .. -

(grading with sand) dark stiff

~ 5 -

~ brown - 22* 11 96 SILT, with some clay tan stirr ML .... -

.... I .. . .. io

SAND (fine-grained), with some tan medium SM- .rx 25* dense SP

.. silt

=IT Pa.ssing #200 Sieve _, 22% .. 18

(grading with coarse-grained sand SW-'" and some fine-grained gravels) SP .. -

- 15 -IT .... - 14 6 '

( gra.ding fine-to coarse-grained SM-'- -gravel in lenses) GM'"" -.. -

~o - -U 22

- -.

ljKA v i:.J.. {tine-to coarse grameai, u.iown- "'"' .... -sandy, with tra.ces of silt and grey SM .... -clay -25 :[ .. 33 4

.... -- -- -..__30 -.... -- -- -

(interbedded lenses of gravelly - -sa.nd) - 35 =I 38 Pas sing #200 Sieve "' 10% -

- -- -

,·.~ - --40 -

'


Peter K•ldveer and Associates CIVIC CENTER OFFICE PARK Fremont, California

G#r.dltli<:Jll Con.I/MU PROJECT NO. DATE BORING

K893- l September 1985 ... o. 3


DAILLRIGContinuous Flight Auger SURFACE ELEVATION -- LOGGW SY DYR

DEPTH TO GAOUNDWATERN ot Established BORING DIAMETER 6 Inches DATE DRILLED 7118185

DESCRIPTION ANO CLASSIFICATION Zw- .· I: 1£ ~ < 0 '.i"" "' ~<~ "' ;: ;; z ;:;; ....

DEPTH ~ ~z z- ~~~~ ~ "' >- " >- ~ w ... z If: IOI~

~FEET) ~ >- ~ ~ " ... QU 0 ri.. ~ ~ SOIL " ~ .. ~z ,. "' DESCRIPTION AND REMARKS COLOR CONSIST. Zwiil "~ -TYPE " 0

"' z "' :t iZ: ~ " Q ~ " GRAVEL (fine-to coar-se-grained), brown very GM

- 41 -I

sandy, trace of silt (continued) and dense I

(thin lenses of silty sand) grey - -

- -- -- 45 -[ 84 7 - - 9~"

- -- .• --so-

(interbedded lenses with silt, - -traces of clay) - -

- -- -- SS -- -- -- -- ---60

60 ... -Bottom of Boring " 6H Feet - -

... -

... -Notes; .. 65 -1. The str-atification lines repr-e- i- -sent the approximate boundaries - -between soil types and the tran- - -sitions may be grad ua!. - -2. for- an explanation of penetra- -70-tion resistance va.lues marked with an asterisk ( *) ' see firnt - - .

page, Appendix A. - -- -- -- 75 -- -- -- -- -...

-ao-


AND ASSOCIATES, INC. CIVIC CENTER OFFICE PARK

Fremont, California Geotftehni<:al con.,1i.na

PROJECT NO. DATE SORING K 893-1 Sept<'1mber-_ 1985 NO 3


Di'llLLRIG Continuous Flight Auger SUFIFACE ELEVATION -- LOGGED av DYR

Ol!PTIHO GROl,INDWATE!Not Established SORING OIA ... ETER 6 Inches DATE OFllLLEO 7 /18/85

~ ij- > " ~ DESCRIPTION ANO CLASSIFICATION >- ~~= .. .: z t: o:: " DEPTH ... ~:: ~ I!!~ " - -~~-.: ..... ~lo.I~~

,,.!.Erl ~ -"' <"' "~ Q i:z; u.I"

Sv1L ... ;; lt ; ~~;~ DESCRIPTION ANO FIEMAFll(S COLOR CONSIST. ~ ... ~ >-TYPE :!'"'!! " ..

" " SILT, with some clay and sand dark very ML 1 -x brown stiff - 39* 14 111 4. 7 - --- I

16 13 I ::i lL'l' , with clay, trace ot sand llght !1rm -lV!L ~-

(very fine-grained) brown - - 6 - 5 --~ - -- -

SAND (fine-grained}, wan traces T1grn 111eu1um blVJ - .• of silt and pea gravel brown dense - .. (thin lenses of very silty clay) -io Passing #200 Sieve "' 45% -_i_ 11 -SAND (fine-to coarse-grained), orown -medium ::JM gravelly, trace of fines dense SW - -- -

- 15 :I 17 4 - • (grading with less gr-avels) - -

- • .... .

"O GRAVEL (fine-to coarse-grained), grey- dense GW· -u 44 . .... sandy, trace of fines brown GM ... -- -- . (interbedded lenses of gravelly medium -25

~rr 26 4 well-graded sand and poorly dense .... gradded sand with some silt) ... -- -

.... -,_30 .... -u 26

- -- -- -(thin lenses of clayey silt) dense - 35 :1 Passing #200 Sieve "' 12% - 36

- -- .. -- -very -40 dense 64



C--ical CanlU/Qfl~ PFIOJfCT NO. DATE SOFllNG K 893-1 3eptember 1985 NO 4


ORILL AlcContin uous Flight Auger SURFACE ELEVATION -- LOGGED SY DYR

OEPTHTOGROUNOWATEANot Established BORING DIAMETER 6 Inches DATE DRILLED 7/18/85

~~; ~ I: Q..,

DESCRIPTION ANO CLASSIFICATION .., > < • ;: z I.I. a:;: ;; z u; 1--

DEPTH '" ..,..,~

~· z- - cl.I c:i' " ~~~ .... w z ;.i.. ~ w ~

~ o= \Oi ~ ~ -~ <'" Q u SOIL lFEETJ

~ ..,~

" 'i ,. "' l,.'I 0.. i::c ~

OESCRIPTION ANO REMARKS COLOR CONSIST. z'" - 0 z~~ TYPE ~II'.~ • u Q ~ ....

G!{]\V t;)", (tine-to 1coarse-grainea] grey- very GVV-

41 - 64 I sandv continued brown dens"' -Bottom of Boring = 4ff Teet - -

- -

- -

- 45 -.... -

Notes: - -1. The stratification lines rep re- - I sent the approXimate boundaries -between soil types and the tran- -so-sitions may be gradual. 2. For an explanation of penetra- - -tion rnsistance values marked - -with an asterisk ( *) • see first - -page, Appendix A. - -

- 55 -- -- -- -- -~60- I

I .... -.... -.... -.... -.... 65 -.... -.... -.... -~ -~70-~ -.... -~ -.... -.... 75 -.... . .... -1-o -.... ,. -'-80 -


CIVIC CENTER OFFICE PARK AND ASSOCIATES, INC. Fremont, California

Gtlortlehnlcal c,,,,.,,,.,,,. PROJECT NO. OATE BORING K893-l Sentember 100' NO 4


Ofllll R1GC!ontinuous Flight Auger SURFACE ElEVATION -- LOGGED BY DYR

DEP'Tli TO GAOUNOWATEFi'lot Established BORING DIAMETER 6 Inches DATE DRILLED 7/18/85 z II.I~ > " -DESCRIPTION ANO CLASSIFICATION 0 " -

.... ~~= = ~ zl.t. 0: .: '.i-DEPTH ~

~~~ .. z - ::ll' r.:i -it_ ~ ... " .. ~wzm • -" "~ = - • Su!L IFUTI ~ .... ;J - .. = -

O!SCAIPTION AHO AIOMAAKS COLOR CONSIST. " ~ii! ii II >- ". -TYPE .. - " " ! c " Q "

SILT, witn some clay, traces of dark stiff ML -l 11 I sand brown - 1 , -:x CLAY, very silty brown stiff CJ,-- 21* 15 99 l. 5 Liquid Limit = 25%

.. =~ Plasticity Index = 10% - 18* 14 109 2.5

Passing #200 Sieve = 80% I - 5 -stiff - -

SILT, ?lay~- tan ML -~~-~- .__ -- -

SAND (fine- grained) , some silt tan loose CL-ML

.. .•

....

GLAY, very silty, trace of sand tan stiff GL- lo -U ML - 8 24

I- ------

SILT, with clay tan stiff ML I- -

SAND, gravelly, trace of-silt grey- dense SM 1 5 :tx Passing #200 Sieve = 8% brown .... 39* I

~ .. -I- -I- --20 .. -J_ 30 .... -

(thin lense of sandy clay) ... -- -I- 25 =er - 40 5

-SILT, clayey tan very ML (interbedded lenses of silty sand mottlec stiff - -and fine-grained sand with with I- -traces of silt) grey >--30

-U .... 20 24 I- -

SAND (fine-to coarse-grained), tan- dense SW-- -with gravels, trace of silt grey SM - -Passing #200 Sieve = 7% - 35 =I - 31

GRAVEL (fine-to coarse-grained), tan- very Gw -sandy, trace of fines grey dense - ,--

- --40

50 I


Peter Kaldv••r and Associates CIVIC CENTER OFFICE PARK Fremont, California

GM>mdltl/al ~'-"' F'AQ.IECT NQ. DATE BOA ING

K 893-1 September 1985 NO. s


ORILLRIG Continuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

OEPTH TO GROUNOWATE~ot E stabl!s hed BORING DIAMETER 6 Inches DATE OAILLEO 7118/85 Zw- ~ ffi ~ ~ DESCRIPTION AND CLASSIFICATION "' Q u t: «: ;; ""' ... OEPTH w ... ~~ " - ~"" ~ ~

~ ~ ... ~ w " ... lo.I z ... >-w w ~ z cc l.JJ Ill ... ,,, ;; Q :.:'. SOIL IFEETJ 2 w~ 0 Q. ¢ ~

DESCRIPTION ANO REMARKS COLOR CONSIST. ~ Zw~ c ,. - ~ ~ ... TYPE ~cc s "' 0"' '-' Q " '-'

- ~ v.c.L pme ,u coarse-gr-ameaJ, tan- very uV' 41 -sandv trace fines <continued) a rev dense - so

Bottom ot Boring _, 4lt Feet - -

... -- --:.5 -

... -Notes: ... l. The stratification lines repre- ... sen the appr-oximate boundar-ies .... between soil types and the tran- --so-sitons may be gradual. 2. For an explanation of penetra-

... -tion resistance values marked ... -with an asterisk ( . ) . see first ... -page, Appendix A. .... -

... 55 -,... -... -... -... -,_60-... -.... -

... -,... -... 65 -.... -... -- -... --70-... -... -... -.... -... 75 -- -- -- -.. --so-


CIVIC CENTER OFFICE PARK AND ASSOCIATES, INC. Fremont, Ca.lifornia

G«Jmchniai Con:tul,,,,,1$ PROJECT NO. DATE BORING

K893-l 'September- i~: NO. 5

I I I I I I I I I I I I I I. I I I I I

ORILLFllGContinuous Flight Auger SURF .. CE ELEV .. TION -- LOGGEO SY DYR

Ol!PTH TO GROUNOWUEFINot Established SORING 01,...,ETER 6 Inches DATE OFllLLEO 7 /18/85

~ .. - ~ > " .. DESCRIPTION ANO CLASSIFICATION .. II.I?::-

"' i: '.f: " :: ;; z .. -.. ••' OEPTI< .. "'z z- - ""~ -"' .. " ~ w. z * • .. "! .... "'~ l'l:IT) j ....

"'~ "' ... Su IL i in ..J ~~ . "' -0£SCRIPTION ANO Rl!MARl(S COLOFI CONSIST. >- z :I :;; TYPE : :I!!! " ! " 0 " <i lL"l , witn some c1ay oark stirr ML

~~ 12 brown

... I ... 38* 16 111 I

CLAY, silty, with some sand brown stiff CL 112. 5 ... - -

~ 22* 12 - -I ... 5 -

... -SAND (fine-to coarse-grained) , brown stiff · SC._ -silty, with clay and some gravels

- SW,_ - i '-'n'"'"' ·-·-··----• -

SAND (fine-to coarse-grained) grey- medium .. brown dense

-io J_ ·--~-~- --·--··--~--~""'--··-·-····--- -- - 19 5 SAND (fine-to coarse-grained), grey medium SM - .. gravelly, trace of fines dense - -

-GRAVEL (fine-to coarse-grained), grey- mediurr. GW

- 15 -[ sandy, trace of fines tan dense GM ... - 16 6

1

. - -- -- -(inter bedded lense of gravelly -20

sand) dense Ll 34 - - lO" 7 .. -- -- -- 25 -- -- -- -- --30 - - 36

Bottom oi Boring - .:Jd Feet - -Notes: - -1. The stratification lines re pre- .. -sent the approximate boundaries - 35 -between soil types and the transi- - -tions may be gradual. - -2. For an explanation of penetra- - -,-tion resistance values marked with - -an asterisk ( *) ' see first page, --.40 -Appendix A.


P•ter Kaldveer and Associates CIVIC CENTER OFFICE PARK Fremont, California

G.o!K/rniQI C-/tMlra ~E'.CTNO. OAT! 80111 .. G

K893-l ieptember 1985 NO. 6


01uLLR1G:ontinuous flight Auger SURFACI; ELEV .. TION -- i.OGGEO av DYR

OEP'TM TO GROUNDW .. TERNot Established BORING 01 .. METER 6 Inches OATE ORlll.EO 7 /18/85

z ... - ,. Q " DESCRIPTION ANO CLASSIFICATION Q 'f .. • .. ..

~ "~ " ;; ;; "' -DEPTH "' z " - _ .. "'z z- j~ :); '.i - "! ..... "' .. Sutl <FEETI i - " :t <O ~ !

0€SCRll'TION ANO FIEM .. RKS COLOR CONSIST. .li ~:...I 8 ,. - ~~ TYPE ~a:;9. " Q

CLAY, silty with some sand dark very CL 1

~ 18

I brown stiff ... -... - 15* 15 94 I 0.9 SILT, clayey, trace of sand and brown firm- ML- ' ... - I organics stiff CL 20* 12 ... -.. 5 -

tan ... -.. -... .. .. ..-io

Ll SAND (fine-grained), silty tan loose SM ... - 9

Passing #200 Sieve = 65% ... -... -... -

(grading with less silt and with medium ... 15 -[ gravel) dense ... - 14 4 ' - --GRAVEC-(fine-to coarse-grained), tan medium GM·

very sa.nd y, trace of fines dense SM ... -~20 ... -LL 20

- -... -... -(thin lense of clayey silt) - 25 -[ - - 25 4

- -... -... -

dense ~30 ... - 38

Bottom of Boring = 3H Feet ... -Notes; ... -1. The stratification lines repre- .. -sent the approximate boundaries ... 35 -between soil types and the transl- - -t!ons may be gradual. - -2. For an explanation of penetra- - ,.-tion resistance values marked with ... -an asterisk ( *) ' see first page, HO-Appendix A.



G.oi.:ilnical ea...,1r.us PllOJECT !ijQ, CATE BORING K 893-1 September 1985 NO. 7


Ol'l•llRIGContinuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

Dl!PTIHO GROUNOWATE~'fot Established SORING DIAMETER 6 Inches DA TE DRILLED 7 /18/85

~ )j; ; > " "' OESCRIPTlON ANO CLASSIFICATION ... .. ~ ' " ;: :;z Ii,. o:: " z <ii -OEPTl< "' ~·~ "'z " - - ~Cl -~ .... *iii. lo.I .;i: ...

~ .... ! .. "' ..... ~"::t': t,lfll l ....

"~ Sv1L ll!;; s j: ~ "~ -De~ll'TION ANO Rl!iMARl(S COlOR CONSIST.

,._ ! ~:;; TYPE :::::! ~ "

SILT, with some clay dark stiff ML 1 16 - - I brown - - ' - -14 15 I

SILT, clayey, trace of sand and tan stiff MT, :~ 15* 17 lOO I 1. 9 -organics 5 - --- -- -- -

(lenses where less clayey and -sandy) -io

-X - 15* 16 97 0.8 ~ - -

- -- -(grading very clayey) CL- - 15 :~ ML - 10 21

' - -- -- -

Liquid Limit = 25% HO firm -l 6 23 Plasticity Index = 7% -Passing #200 Sieve = 90% - -x ,_ --- -stiff ... 25 :x ... 15* 22 97 1. 0

~-- -(thin lense of fine-grained sand - -with trace of silt) ... -(grading to traces of clay) ,...30

SW' 17 SAND, gravelly grey dense - - b"" Bottom of Boring = 3B Feet ... -Notes: - -1. The stratification Jines rep re- - -sent the approximate boundaries ... 35 -between soil types and the transi- I- -tions may be gradual. ... -2. For an explanation of penetra- ... -.. tion resistance values marked with ... -an asterisk ( *) • see first page. 1-<oo -Appendix A.



G«>mdmit:lll Conal/-t$ PRO.ll!CT NO. DATE BOIUPIG

September 1985 NO. 8

K 893-1


DAILLR10:::ontinuous Flight Auger SURF,.CE ELEV,.TION -- LOGGED BY DYR

DEPTMTOGROUNDW ... TEFNot Established BORING 01,.METER 6 Inches o ... TE DFHlLED 7118/85 % 11.1""":" I:: " ~ DESCRIPTION AND CLASSIFICATION .. " " .... • II.I::::::= = ;z Iii. " - ;; z"' -DEPTH ~ <<' ~i z- - "J"i ~ -

~ ........ ~loo z ~ - "' ;o .~

w ... IF£iTl 2

" " .. :l!. Su•L < IM~ 0

;o ~ ".. -DESCRIPTION AND REMARKS COLOR CONSIST. " z"' ... >- .z ~ ~ TVPE 't .. $ " Q ~..,

dlL'l', clayey, trace of sana brown very CL

~~ 23 Liquid Limit = 26% stiff - l I Plasticity Index = 9% - 23* 14 Passing #200 Sieve = 85% tan -

~z - 20* 13 116 8. 1

- s -- -- -- I --lo

SM- -~ 15* 17 92 0. 7 -ML . -CLAY, very silty tan firm CL -SILT, clayey, sandy (fine-

' tan firm ML

grained) - -(grading without sand) - 15 -I - 18 3

' GRAVEL (fine-to coarse-grained), brown- medium Ci c.; sandy, trace of clay dense - -grey - -- -(grading with less clay and less -20

J_ 22 sand in lenses) - -

- --SAND (fine-to coarse-grained), brown medium SC .. -with gravel and some sand) dense .. 25 -(thin interbedded lenses of silty '.I sand and clayey silt, clayey sand) - - 28

Passing #200 Sieve = 14% .. -- -.. -

dense -30 - .J_ 33 25 ... -"" -.. -.. 35 -I "" - 33

SAND (fine-grained), with some brown dense SC ... -gravel and clay .. -' .

... -HO

36 6



~OldmiQI COll:tulDtlfl PROJECT NO. DATE BORING

K893-1 September 1985 !iO. 9

I I I I I I I I I I I I I I I

I I I

DAILL RIGCOntinuous Flight Auger SURFACE ELEVATION -- LOGGED BY DYR

DEPTii TO GROUNDWATERNot Established BORING DIAMETER 6 Inches DATE DRILLED 7118/85

z i..1""":' . j: Q'"

DESCRIPTION ANO CLASSIFICATION 0 " ... '" > ' "' ~ zli. "' ;: ;;; z t:; ""' DEPTH "' <<~ ~z z- - II) Cl ,.... - ~I.ii z ~ • ..... ~ "'t'l ... 00 . '" o~w~

SOIL IFE.ET) , ~~9 ;: ... 0 "- u ~ ;= -DESCRIPTION AND REMARKS COLOR CONSIST. • ~ ,. -

TYPE "' ~~~ ~ ! 0 00

" Q " SAND (fine-1rained), with i1ome brown dense SC

41 -36 6

aravel and c av I continued I· -Bottom of Boring = 41!: Feet - -- -- --~5 -- -Notes: - -1. The stratification lines rep re- -sent the approximate boundaries -between soil types and the transi- >--50-tions may be gradual. 2. For an explanation of penetra- - -tion resistance values marked - -with an asterisk ( *), see first - -page, Appendix A. - --55 -- -- -- -

- --60-- -- -... -... -- 65 -- -- -- -- --10-... -... -- -- -- 75 -- -- -- -- -,. -80- I


CIVIC CENTER OFFICE PARK AND ASSOCIATES, INC. Fremont, California

G.or.clmial Conru/mnrs PROJECT NO. OATE BORING K893-l 3eptember 1985 NO 9

I I I I . 1 I I I I I I I I I I I I I I

OAILLRIGContinuous Flight Auger SUAFACE ELEVATION -- LOGGEO av DYR

oePnt TO GAOUNOW ... TEft\Jot Established BOAING OIA!olETER 6 Inches o ... re DRILLEO 7/18/85

~~: ~ ,..

"'~ DESCRIPTION ANO CLASSIFICATION ~ ....

~~= .. o:;;. " OEl'TH - ~~~ "'z :- - Ill !.:I ~ II.. \II. z ...

~ _:;;! :;:- .. .. .. z iz; ... y'I

Sv'L l,1!£Tl 2 .. " ;i:; " 1' ~II. a::~

Ot:SCRIPTION ANO REMARKS COLOR CONSIST. ~ ~!iii ~ ,. - ! ~:;; TYPE u "' ~ - " SILT, with some clay, trace of dark stiff ML 10 sand brown - 1 -,___

I ... - 8 ' - --~ I SILT, with clay tan stiff ML 10 ... -- -··· 5 Bottom of Boring - 4,\ Feet - -- -- - I - - I -Note: -io-The stratification line repr:esents the approximate boundary between - -soil types and the transitions may - -be gradual. ... -... .

.. 15 -

... - ' ... -

.... -- . -20-.... -.... -.... . ... . - 25 -- -.... -.... -... -.... 30-.... -- -.... -.... -.... 35 -- -- -- -,. - -ko-


Peter Kaldveer and Associates CIVIC CENTER OFFICE PARK Fremont, California r;.o-- Conwl-ts f>l'().JECT NO. o ... n: SORING

K893-1 September 198~ NO. 10


oRILLRIG Continuous Flight Auger SURFACE ELEVATION -- LOGGEO BY MAS

ol!PTH TO GROUNOWATI;RNot Established BORING OIAMETER 6 Inches OA TE ORILLEO 7/24/85

! ... .., ,.. s ~::: OESCRIPTION ANO CLASSIFICATION • >-.. =~:: a:;: ;; "' ••' z~-

DEPTH ~z z.., - 1ll tj -

~ a: - .. "' .. ~ w z;;, _ .. ,. < "'

S<l•L l,!UJ ~

:l!;; 0 j: ~ o~ u :f i ~ Ot:SClllPTIOH ANO Rl!MARKS COLOR CONSIST. ...~ ~ ,. - ! ~:;; TYPE : i:c !. ..

0

SILT, clayey brown dense ML .. I - . ... - ' ' ... -(grading fine-grained sand) .. .

- 5 -- . - . - ..

--io--

SAND (fine-r;rained); silty: trace brown medium SM - -gravel dense - -.. .

.. 15 :[ 16 .. ' (grading with medium-to coai:se- SW - .

grained sand and gravel) - . - -T -20- 17

Bottom of Boring = 201! t eet - -- . - .

N0te: - . The stratification line represents -25 -

the approximate boundary between - -soil types and the transition may - . be gradual. .. -.. -

-30-- . - -- -- -- 35 -- -- -- -- . -40 -



13-oo.dlnicai <:DnwtDfla PROJECT NO. oATI; BORING K893- I September lgjS NO. 11


DAILL RIGContinuous Flight Auger SURl',O.CE ELEVUION -- LOGGED av MAS

DEPTH TD GROUNOW,O.TEllNot Established BORING 01,0.MfTER 6 Inches DATE DRILLED 7/24/85

!jj; . · > 0 '!: • DESCRIPTION ANO Cl..ASSIFICATION .... .. ;: :z ~ "' - ;;; i ~ ~

OEPTl't ~ <<' " - - ~ ~ -it ..... ..... ·- :z l.i; :jj _ .. J "~

w~

S.;i'L ur:Em 2 !C9 J~ "' IC r.:i i::c er ..:; < ~~;-DESClllPTION ,O.NO REMARKS COLOR CONSIST. TYPE .. ~ >-

~i:cS u " ... CLAY, silty brown stiff CL .. 1 -

... -

... -.. -

... 5 -.. -

... -

... -

.... '-iO-.. -.. -

(grading with some very fine- firm .. -grained sand lenses) .. :[ .. 15 5 .. .

... . L .

SAND, gravelly brown medium SW .. -dense

---20-x 48*

bOlLOm or ;;onng .cu~ Feet ~ -.... -... -

Notes: .. -1. The stratification line rep re- "'25 -sents the a.pproximate boundary .. -between soil types and the transl- .. -tion may be gradual. ... -2. For an explanation of penetra-tion resistance values marked

.. -with an asterisk ( *) ' see first

.... 30 _

page, Appendix A. .. -. -- -- -• 35 -- -- -- -'. - --40 -


Peter Kaid veer and Associates CIVIC CENTER OFFICE PARK Fremont, Califor-nia

G.o-icll eon.,1mna PROJECT NO. DATE BORING

K 893-1 September 1985 NO. 12

I I I I I I ,, I I I I I I I I I I I I

K893-l, 07524a, 2

APPENDIX B - LABORATORY INVESTIGATION

The laboratory testing program was directed toward a quantitative and qualitative evaluation of the physical and mechanical properties of the soils underlying the site.

The natural water content was determined on forty-eight samples of the materials recovered from the borings in accordance with ASTM Test Designation D-2216. These water contents are recorded on the boring logs at the appropriate sample depths.

Dry density determinations were performed on fourteen samples of the subsurface soils to evaluate their physical properties. The results of these tests are shown on the boring logs at the appropriate sample depths.

Atterberg Limit determinations were performed on four samples of the subsurface soils to determine the range of water content over which these materials exhibit plasticity. The A tterberg Limits were determined in accordance with ASTM Test Designations D-428 and D-424. These values are used to classify the soil in accordance with the Unified Soil Classification System and to indicate the soil's compressibility and expansion potentials. The results of these tests are presented on Figure B-1 and on the logs of the borings at the appropriate sample depths.

An expansion test was performed on a sample of the surface soils. This test was performed in accordance with U. B. C. Standard No. 29-2. The results of the expansion teat are shown below.

Molded Moisture Content (%)

10

Initial Dry Density (pcf)

110

Expansion Index

43

he percent passing the #200 sieve was determined on eleven samples of the subsurface soils to aid in the classification of these soils. These tests were performed in accordance with ASTM Test Designation D-1140. The results of these tests are shown on the boring logs at the appropriate sample depths.

Unconfined compression tests were performed on twelve undisturbed samples of the clayey subsurface soils to evaluate the undrained shear strengths of these materials. The unconfined tests were performed in accordance with ASTM Test Designation D-2166 op. samples having a diameter of 2. 4 inches and a height-to-diameter ratio of at least two. Failure was taken as the peak normal stress. The results of these tests are presented on the boring logs at the appropriate sample depths,

A consolidation test was performed on an undisturbed sample of the subsurface clays to assist in evaluating the compressibility characteristics of this material. The consolidation test was performed in accordance with

............... , •1&.lllL

' I I I I I I I .I I I I I I I I I I I

K893-l, 07524a, 3

ASTM Test Designation D-2438-70. The results of the consolidation test are presented graphically on Figure B-2.

A resistance "R" value test was performed on a representative sample of the surface soils at the site to provide data for pavement design. The test was performed in accordance with California Test Method 301-F and indicated an "R" value of 12 at an exudation pressure of 300 pounds per square inch. The results of the test are presented below:

RESULTS OF uR" VALUE TEST

Dry Water Exudation Expansion Description Density Content Pressure Pressure "Rn

of Material (pcf) (%) (psi) (psf) Value

Brown Silty 111 16 255 39 4 CLAY with some 114 15 310 52 13 Sand (CL) 116 14 414 74 21

11Ru Value ~ 12 at Exudation Pressure of 300 psi

,.

---- "'"""""·

I I I I

' I I I l I .1 I I I I I I I I

"' .... '-'

>< LIJ c ~ ,. I-

Q I-

"' <( ...J 0..

KEY SYMBOL

®

~

Iii

®

Peter

60

/ 50 ~·

CH •' "'""<(, 40

·~

v .

/ CL

30 -··

/ MH ~ or- --20

10 ®/ OH

" 7 j'// ~ ML or OL 4 c;_~=-~~

ML I 0

0 10 20 30 40 50 60 10 80 90 100

LJOUIO LIMIT (%)

ATTERBERG LIMITS UNIFIED SAMPLE NATURAL LIQUID PLASTICITY LIOUIOITY PASSING SOIL BORING OEPTH WATER LIMIT INOEX INDEX NO. 200 CLASSIFICA-NO.

CONTENT SIEVE TION (feet) % % % % SVMBOL %

5 2.5 15 25 10 -o. 1 80 CL

8 21 23 25 7 0.8 90 CL-ML

9 2.5 14 26 9 -0. 3 85 CL

S-1 Exp. -- 32 14 --~- 79 CL

,.

PLASTICITY CHART AND DATA Kaid veer and Associates


Geotechnical Consultants PROJECT NO DATE

Figure B-1 K893- l Septe_mber 19%


.00

,.., "' .04 <.J .s .._ ., i

<.J

.s ,_,.,

z . 06 .... ;;:; i;..

"' =;j '-' .... ~ .08 ~

0.1 1.D 10 NORMAL EFFECTIVE PRESSURE - KSF

SAMPLE DATA CONSOLIDATION TEST DATA aOflUNGI HO.:

DEPTH IO-)' 21-23 lliLEVATION (ft.):

Dli..::RtPTION, Grey-Yellow-Brown Silty CLAY with fine- rained Sand CL

PETER KALDVEER

AND ASSOCIATES, INC.

INlflAL.

OlllV DINAITV (ref)

MOl.,,_,U. COMTINT 1%) 22. 6 YOIDMTIO . 650 OIGMa or U.tUMTION 1~1 93.9 HllGHTUn.) . 7500

CONSOLIDATION DATA


l'l'IOJECT NO.

100

··-18. 4 . 496 100.0 . 6800

K893- l September 198 Figur• B-2

I I I J, I l I I I I I I I I I ,,, I t I

K893-1, 07524a, 4

1. GENERAL

APPENDIX C GUIDE SPECIFICATIONS - SITE EARTHWORK

FOR CIVIC CENTER OFFICE PARK

FREMONT, CALIFORNIA

A, Scope of Work

These specifications and applicable plans pertain to and include all site earthwork including, but not limited to, the furnishing of all labor, tools, and equipment necessary for site clearing and stripping, disposal of excess materials, excavation, preparation of foundation materials for receiving fill, and placement and compaction of fill to the lines and grades shown on the project grading plans.

B . Performance

The Contractor warrants all work to be performed and all materials to be furnished under this contract against defects in materials or workmanship for a period of years(s) from the date of written acceptance of the entire constructionwol'k by the Ownel'.

Upon written notice of any defect in materials or workmanship during said year period, the Contl'actol' shall, at the option of the Ownel', repair

or replace said defect and any damage to othel' work caused by or resulting from such defect without cost to the Owner. This shall not limit any rights of the Owner under the "acceptance and inspection" clause of this contract.

The Contractol' shall be l'esponsible fol' the satisfactory completion of all site earthwork in accordance with the project plans and specifications. This work shall be observed and tested by a representative of Peter Kaldveer and Associates, Inc. , hereinaftel' known as the Soil Engineer, Both the Soil Engineer and the Architect/Engineel' al'e the Owner's representatives, If the Contractor should fail to meet the technical Ol' design requirements embodied in this document and on the applicable plans, he shall make the necessary readjustments until all work is deemed satisfactory as determined by the Soil Engineer and the Architect/Engineel'. No deviation from the specifications shall be made except upon written approval of the Soil Engineer Ol' Architect/Engineer.

No site earthwork shall be performed without the physical presence or approval of the Soil Engineer, The Contractol' shall notify the Soil Engineer at least twenty-four hours prior to commeneement of any aspect of the site earthwork.

The Soil Engineel' shall be the Ownel''s repl'esentative to observe the grading operations during the site preparation work and the placement and compaction of fills. He shall make enough visits to the site to familiarize himself generally with the progress and quality of the work. He shall make a sufficient number of tests and/or observations to enable him to

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form an op1mon regarding the adequacy of the site preparation, the acceptability of the fill material, and the extent to which the compaction of the fill, as placed, meets the specification requfrements. Any fill that does not meet the specification requirements shall be removed and/or recompacted until the requirements are satisfied.

In accordance with Contractor shall be conditions at the job during performance continuously and shall

generally accepted construction · practices, the solely and completely responsible for working

site, including safety of all persons and property of the . work. This requirement shall apply not be limited to normal work hours.

Any construction review of the Contractor's performance conducted by the Soil Engineer is not intended to include review of the adequacy of the Contractor's safety measures in, on or near the construction site.

Upon completion of the construction work, the Contractor shall certify that all compacted fills and foundations are in place at the correct locations, have the correct dimensions, are plumb, and have been constructed in accordance with sound construction practice. In addition, he shall certify that the materials used are of the types, quantity and quality required by the plans and specifications.

C. Site and Foundation Conditions

The Contractor is presumed to have visited the site and to have famillarfaed himself with existing site conditions and the soil report titled, 11 Geotechnical Engineering Services, Civic Center Office Park, Fremont, California", dated September 16, 1985. The Contractor shall not be relieved of liability under the contract for any loss sustained as a result of any variance between conditions indicated by or deduced from the soil report and the actual conditions encountered during the course of the work.

The Contractor shall, upon becoming aware of surface and/ or subsurface conditions differing from those disclosed by the original soil investigation, promptly notify the Owner as to the nature and extent of the differing conditions, first verbally to permit verification of the conditions, and then in writing. No claim by the Contractor for any conditions differing from those anticipated in the plans and specifications and disclosed by the soil investigation will be allowed unless the Contractor has so notified the Owner, verbally and in writing, as required above, of such changed conditions.

D. Dust Control

The Contractor shall assume responsibility for the alleviation or prevention of any dust nuisance on or about the site or off-site borrow areas. The Contractor shall assume all liability, including court costs of codefendants, for all claims related to dust or windblown materials attributable to his work.

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II. DEFINITION OF TERMS

STRUCTURAL FILL - All soil or soil-rock material placed at the site in order to raise grades or to backfill excavations, and upon which the Soil Engineer has made sufficient tests and/ or observations to enable him to issue a written statement that, in his opinion, the fill has been placed and compacted in accordance with the specification requirements.

ON SITE MA TE RIAL Material obtained from the required site excavations,

IMPORT MATERIAL - Material obtained from off-site borrow areas.

ASTM SPECIFICATIONS - The 1980 edition of the American Society for Testing and Materials Standards.

DEGREE OF COMPACTION - The ratio, expressed as a percentage, of the in-place dry density of the compacted fill material to the maximum dry density of the same material as determined by ASTM Test Designation D 1557-78.

Ill. SITE PREPARATION A. Clearing and Grubbing

The Contractor shall accept the site in its present condition and shall remove from the area of the designated project earthwork all obstructions including billboards, any underground irrigation lines or utilities, upnsers, asphaltic concrete, concrete rubble, designated trees and associated roots and any other matter determined by the Soil Engineer to be deleterious. Such material shall become the property of the Contractor and shall be removed from the site. Holes resulting from the removal of underground obstructions that extend below finish grades shall be cleared and backfilled with structul'al fill.

B. Stripping

Where vegetation exists, the site shall be stripped to a minimum depth of 3 inches or to l!uch greater depth as the Soil Engineer in the field may consider as being advisable to l'Smove all surface vegetation and Ol'ganic laden topsoil. Stripped topsoil with an organic content in excess of 3 percent by volume shall be stockpiled for possible use in landscaped areas.

IV. EXCAVATION

All excavation shall be performed to the lines and grades and within the tolerances specified on the project grading plans. All ovel'Sxcavation below the gradel! specified shall be backfilled at the Contractor's expense and shall be compacted in accol:'dance with the specifications. The Contractor shall assume full responsibility fol' the stability of all temporary construction slopes at the site.

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V. SUBGRADE PREPARATION

Sul'foces to l'eceive compacted fill, and those on which concl'ete slabs and pavements will be constl'ucted, shall be scarified to a minimum depth of 6 inches and compacted. All l'uts, hummocks, ol' other uneven surface features shall be removed by surface grading priol' to placement of any fill materials. All areas which are to receive fill material shall be appl'oved by the Soil Engineer prior to the placement of any fill material,

VI. GENERAL REQUIREMENTS FOR FILL MATERIAL

All fill material must be appl'oved by the Soll Engineer. The material shall be a soil Ol' soil-rock mixture which is free from Ol'ganic matter or other deleterious substances. The fill material shall not contain rocks or rock fl'agments over 6 inches in gl'eatest dimension and not more than 15 percent shall be over 2. 5 inches in greatest dimension, On-site material having an organic content of less than 3 percent by volume is suitable fol' use as fill in all areas except where non-expansive import material is specified.

All imported fill material shall be nonexpansive with a plasticity index of 12 or less.

VII. PLACING AND COMPACTING FILL MATERIAL

All structural fill less than 5 feet thick shall be compacted by mechanical means to produce a minimum degree of compaction of 90 percent as determined by ASTM Test Designation D 1557-78. All structural fill greater than 5 feet in thickness and the engineered fill layer below footings and mat shall be compacted to at least 95 percent relative compaction. Field density tests shall be performed in accordance with either ASTM Test Designation D 1556-64 (Sand-Cone Method) or ASTM Test Designation D 2922-71 and D 3017-72 (Nuclear Probe Method). The locations and number of field density tests shall be determined by the Soil Engineer. The results of these tests and compliance with these specifications shall be the basis upon which satisfactol'y completion of work shall be judged by the Soll Engineer.

VIII. TRENCH BACKFILL

Pipeline trenches shall be backfilled with compacted structural fill placed in lifts not exceeding 8 inches in uncompacted thickness. If onsite soil is used, the material shall be compacted by mechanical means to a minimum degree of compaction of 85 pel'cent. lmported sand may also be used for backfilling trenches provided it is compacted to at ieast 90 percent. If impol'ted sand backfilling is used, sufficient water shall be added during the trench backfilling operations to prevent the soil from bulking during compaction. In all building pad and pavement areas, the upper 3 feet of trench backfill shall be compacted to a minimum degree of compaction of 90 percent for onsite soils and 95 percent where imported sand backfill is used.

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IX. TREATMENT AFTER COMPLETION OF EARTHWORK

After the earthwork operations have been completed and the Soil Engineer has finished his observation of the work, no further earthwork operations shall be performed except with the approval of and under the observation of the Soil E ng:ineer.

It shall be the responsibility of the Contractor to prevent erosion of freshly gt'aded areas during construction and until such time as permanent drainage and erosion control measures have been installed.

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APPENDIX D GUIDE SPECIFICATIONS - PILE FOUNDATION

FOR

PART 1 - GENERAL

1.01 SCOPE


The work consists of furnishing all plant, labor, equipment, appliances and materials required to install all piles as shown on the plans and as herein specified. These specifications include cutting off piles to the required elevations but do not cover pile caps. ·

1.02 SUBMITTALS

A. Shop drawings for piles to be fabricated, conforming to all applicable requirements of these specifications.

B. Piling layout detailed on drawing indicating location of each pile, including penetration, tip elevation, cutoff elevation and assigned number for each pile as identification in pile driving record thereafter.

C. Manufacturer's publications and information equipment including tabular or graphic particular hammer to be used.

1.03 JOB CONDITIONS

related to pile driving driving data for the

A. Clean-up: Upon completion and acceptance of all specified work, the Contractor shall promptly remove from the site all unused piles, or construction materials, equipment or supplies, and shall leave the work area in a satisfactory condition.

B. Surface Conditions: A geotechnical investigation has been performed at the site. Records of the borings made at the work site are available at the Geotechnical Engineers office. These records pertain to conditions at the boring locations.

1. Contractor shall review the logs and geotechnical report, make a personal inspection of the site, and otherwise satisfy himself as to the conditions affecting the work. No claims for extra compensation or extension of time will be allowed on account of subsurface conditions inconsistent with the data given.

C. Inspection: The Geotechnical Engineer will review and inspect the driving of piles. Deviations to the criteria herein specified shall have the prior approval of the Geotechnical Engineer.

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PART 2 - PRODUCTS

2.01 PILE DRIVING EQUIPMENT

A. General; The Contractor shall furnish pile driving equipment as approved by the Geotechnical Engineer. The Contractor shall furnish and maintain at the site, and subsequently remove from the site as his property, all equipment and appurtenances, including spuds, as required, to satisfactorily install all piles furnished under this Contract, all in accordance with the requirements set forth herein. Driving equipment shall be maintained and operated in accordance with the manufacturer's instructions at all times.

B. Pile Driver: The pile driver shall have fixed leads which shall be capable of guiding the hammer from the highest to the lowest point of travel and holding the pile firmly in axial alignment with the hammer. Leads shall be secured to the body of the crane or supporting tower by rigid members in a manner that will prevent movement and maintain alignment of the leads at all times during driving operations. Swinging leads shall be used only with the prior approval of the Geotechnical Engineer.

C. Pile Hammer:

1. The pile hammer shall be an approved diesel hammer capable of delivering a minimum rated driving energy of 30, 000 foot-pounds per blow when operated at the rated number of blows per minute specified by the manufacturer. The hammer shall be in first-class condition, equipped with all appurtenances necessary for safe, efficient driving, provided with a suitable head which will not damage the pile, and be capable of consistently developing the manufacturer's rated energy.

2. The Contractor shall submit to the Geotechnical Engineer for review the manufacturer's specifications and catalog for all hammers proposed for use. The adequacy of the hammer shall be subject to the Geotechnical Engineer's review.

D. Cushion Devices:

1. Cushion devices shall be suited to precast prestressed piles and to the hammer employed, as approved Geotechnical Engineer.

concrete by the

2. Followers, if used, shall be made of steel, shall have an average weight of not less than 80 pounds per foot, and shall be of a type that will adequately and properly transmit the energy of the hammer blow to the pile head. The driving head and cap shall be made to fit snugly over the pile head. Timber followers of any type will not be permitted.

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E. Driving Caps: Driving caps shall be designed to distribute the hammer blow uniformly throughout the cross section of the pile. Design of the driving cap shall be approved by the Geotechnical Engineer.

2. 02 PRE CAST, PRES TRESSED CONCRETE PILES

A. General: The Contractor shall furnish at the job site precast, prestressed concrete piles of the sizes and lengths shown on the plans to meet the requirements of these specifications, including handling, transporting, storing and performing other related work, all in accordance with the requirements specified herein.

B • Concrete:

1 • Concrete for prestressed piles shall have a minimum compressive strength of 6, 000 psi at 28 days, as determined from breaks of concrete cylinders made, cured and tested in accordance with the requirements specified herein. The concrete mix shall be so proportioned to contain not less than 7 nor more than Bi sacks of cement per cubic yard of concrete, with the maximum net water content not to exceed 5 gallons per sack of cement, and to produce a workable concrete complying with the specified stl'ength l'equil'ements. No admixtures of any kind will be pel'mitted. The Contractor shall submit his concrete mix design, together with supporting test data from an approved commercial testing laboratory to the Structural Engineer for review prior to commencing manufacture of piling.

C. Prestressing Steel:

1. Prestressing steel shall be high-tensile, stress relieved 7-wire strand conforming to the requirements of ASTM A416, Gl'ade 270, or high-tensile, stress relieved wire conforming to the requirements of ASTM A421. All strands shall be stress relieved as a unit, after the wires have been formed into a strand.

2. Pick up points shall be determined by the Contractor and clearly marked fol' handling crews. Piles shall also be marked clearly with the date of casting and length of pile.

D. Spiral Reinforcement:

1. Spiral reinforcement shall conform to the strength requirements of ASTM A615 or shall be cold-drawn steel wire conforming to ASTM A82. ,.

2. The Contractol' shall be responsible for planning, coordinating and carrying out the various functions associated with the design, manufacture, handling, tl'ansportation and storage of the precast. prestressed concrete piles.

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E. Concrete Test Cylinders:

1. At least two sets of concrete test cylinders, consisting of 4 cylinders per set, shall be taken from each day's casting pour, but not less than two sets shall be taken from each 50 cubic yards of concrete poured. One-half the number of cylinders shall be stored and cured under laboratory conditions. The remainder of the cylinders shall be cured under conditions of curing similar to those to which the piling will be subjected.

2. Compression tests shall be made from the same sets by the Contractor at 3, 7, 14 and 28 days in accordance with the requirements of ASTM C39, for the purpose of determining when release of prestressing steel may be commenced. The minimum compressive strength at time of release of prestressing steel shall be 4000 psi. This determination shall be based on the strength of the field-cured cylinders.

F. Curing: All precast concrete piles shall be adequately protected from weather, sun and mechanical damage until thoroughly set and the strength thereof is sufficient to prevent damage. All piles shall be cured either by the water method, or by steam curing. Methods and details shall be subject to approval by the Structural Engineer.

PART 3 - EXECUTION

3.01 TRANSPORTATION AND STORAGE

A. Transportation: Extreme care shall be exercised in handling and moving precast concrete piles to prevent cracking or damage.

B. Storage: Units damaged by improper or careless storing or handling shall be replaced by Contractor at his expense.

3. 02 INSTALLATION OF PRECAST, PRESTRESSED CONCRETE PILES

A. Condition of Pile before Driving:

1 . Precast concrete piles shall not be driven until they are inspected and approved by the Geotechnical Engineer and until breaks of concrete test cylinders, made from the concrete pour for the piles, and cured under conditions similar to those for the piles, show a strength of at least 6, 000 pounds per square inch (psi).

2. The Contractor shall mark each pile promim!htly with black paint at 1 foot intervals over the entire length of the pile, starting at the tip, Each 5 foot interval shall be numbered in consecutive order.

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B . Protection of Pile Head:

l . All pile heads shall be protected during driving with an approved driving cap or cushion device. The inside diameter of the cap shall be such that the pile head makes a loose fit inside the cap,

2. Cushion devices shall be continually inspected during driving and shall be replaced when they become unduly worn or compacted.

C. Observation and Recording of Pile Driving Behavior:

1. Pile behavior during driving will be monitored and recorded by the Geotechnical Engineer, No driving shall be done without the presence of the Geotechnical Engineer. The Geotechnical Engineer will record the driving resistance in blows per foot for each foot of the entire driven length of all piles.

2, When driving is interrupted before final penetration is reached, the delay time shall be recorded at the corresponding pile depth on the pile driving record. The blow counts for the first 3 feet after the delay will not necessarily be considered as termination resistance.

D. Driving:

1. All piles shall be driven continuously to the designated cutoff elevation unless refusal is encountered prior to reaching the specified tip elevation. Pile driving can be terminated if refusal is met before reaching the specified tip elevation, as approved by the Geotechnical Engineer.

2. The refusal criteria given below is typical and only for the hammers indicated. Actual driving criteria shall be determined by the Engineer based on the initial driving of piles.

Pile Type

Precast concrete; 12- and 14-inch square

E. Accuracy in Driving:

Hammer Energy

(ft-lbs)

30,000

Refusal Blow Count (Blows per Last Foot)

90

'.

1. All piles shall be driven in true alignment at the locations shown on the plans. Each pile at cutoff elevation shall not vary more than 3 inches from the position shown on the plans. Templates or other approved means shall be used to obtain the required accuracy. Manipulation of piles into alignment or position will not be permitted.

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2, All piles shall be driven plumb. Variation shall be not more than 2% from vertical on any section of pile length unless approved by the Structural Engineer.

3. If the allowable pile deviations are exceeded, the Geotechnical Engineer may direct that the pile be withdrawn and another pile driven at the correct location. All costs associated with such replacement piles or additional construction or work caused by piles being out of place shall be borne entirely by the Contractor.

Redriving: installation in addition

All piles which are raised more than l inch during the of adjacent piles shall be redriven a minimum of 6 inches to the raise, at the sole expense of the Contractor.

G. Driving Sequence: Driving sequence in pile group shall begin at center of group; then shall proceed from center outward.

H. Predrilllng: Predrilllng can be used to within 5 feet of the required tip elevation. Predrilling will be with a continuous flight auger only.

I. Reduction of Hammer Energy: When driving through soft soil of little or no resistance to penetration, length of stroke of hammer shall be reduced to prevent longitudinal tensile stresses in pile shaft. When point of pile is being driven into firm ground, full stroke of hammer shall be used.

J. Piles Driven Deeper than Minimum Penetration: Minimum penetration for piles, as specified, is based on obtaining sufficient support resistance in subsurface soils to support the pile design loads. If, in the opinion of the Engineer, sufficient bearing is not reached at planned penetration, he may direct the Contractor to either drive the pile deeper or to abandon the pile and driven another, longer, pile at a substitute location designated by him. If the pile is overdriven by the Contractor without the approval of the Geotechnical Engineer, then construct a pile extension to the designated cutoff elevation at no cost to the owner. Design of the pile extension shall be approved by the Structural Engineer.

K, Cutoffs:

1. Piles which have reached maximum driving resistance, as determined by the Geotechnical Engineer, shall be cut off at the elevations shown on the plans, or as direc~d by the Structural Engineer. Cutting shall be done with approved equipment that will not fracture or damage the area below the cut surface.

2 , When the pile will be cut off such that 2 feet or more of flexible tubing inserts will remain embedded in the pile head, prestressing strands shall be cut or burned off at the cutoff elevation. Anchorage to pile cap shall be made with reinforcing

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steel dowels grouted in the flexible tubing inserts, as shown on the plans.

3. When the pile will be cut off such that less than 2, 5 feet of flexible tubing inserts will remain embedded in the pile head, the holes for dowels shall be cored to a minimum of 30 inches, and dowels installed for anchorage to pile caps in conformance with details shown in plans. Special care will be taken while coring to avoid fallout of inner surfaces, tensile cracks and separation of concrete from strands.

4, All concrete pile cutoffs not used in splices or extensions, regardless of length, shall become the property of the Contractor, and shall be disposed of in a legal manner.

5, All costs associated with pile cutoffs two feet or greater in length will be paid for by the Contl'actor. All costs associated with pile cutoffs less than two feet in length will be paid by the ownel'.

L. Unsatisfactol'y Piles:

1. Any pile which is misaligned, impropel'ly installed or damaged in any way as a result of the Contractol'1s operations to an extent that, in the Geotechnical Engineel''s opinion, it is incapable of pel'fol'ming the function for which it was designed, will be considered unsatisfactory. Unsatisfactory piles shall be withdrawn and removed from the site of the work by the Contractor at his expense, or, if approved by the Structural Engineer, abandoned and the upper section removed, as designated by him. The Contractor shall replace all unsatisfactory piles with piles satisfactorily installed in accordance with the requirements specified herein.

2. The Contractor shall be responsible for all damage to piles until they are incorporated into the work and the work officially accepted by the Owner.

3. No payment of any kind will be made for furnishing, driving, withdrawing, removing, abandoning, cutting off or any other work associated with piles which are unsatisfactory,

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1. GENERAL

APPENDIX E GUIDE SPECIFICATIONS - ASPHALT PAVING

FOR CIVIC CENTER OFFICE PARK

FREMONT, CALIFORNIA

This portion of the work shall include all labor, materials, tools and equipment necessary for and incidental to the completion of the pavement shown on the plans and as herein specified.

U. DEFINITION OF TERMS

PAVEMENT - Both asphalt concrete, and aggregate base materials.

SUBGRADE - That portion of the construction on which asphalt concrete and aggJ:"egate base is to be placed.

STANDARD SPECIFICATIONS - Standard Specifications of the State of California Department of Transportation, January 1981.

ASTM SPECIFICATIONS - The 1980 edition of the American Society for Testing and Materials Standards.

Ill. MA TE RIALS

A. Asphalts;

(1) Asphalt for prime coat shall be liquid asphalt, grade MC-70 conforming to the provisions of Sections 39 and 93 of the Standard S pacifications.

(2) Asphalt for tack coat and seal coat shall be SS-lh asphalt emulsion conforming to Sections 37 and 94 of the Standard Specifications.

(3) Paving asphalt to be mixed with aggregate shall be steam refined asphalt conforming to the provisions of Section 92 of the Standard Specifications for viscosity grade AR 4000.

B. Mineral Aggregate for Asphalt Concrete;

Type B Aggregate as specified in the Standard Specifications, Section 39, 314 inch maximum sfae, medium grading.

IV. CONSTRUCTION

A. Existing Pavement:

Remove the existing asphalt concrete and base to the subgrade elevation. Existing pavements which are removed can be used as fill material provided

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the asphalt is broken up to meet the maximum allowable size requirements for imported fill material.

B. Sub grade Preparation:

The Contractor shall prepare the surface of the various subgrades receiving subsequent pavement courses to the lines, grades and dimensions given on the plans. Isolated unstable areas shall be stabilfaed by recompaction or excavation and replacement of materials. The upper 6 inches of the subgrade soil shall be compacted to a density not less than 95 percent of that obtained in the laboratory according to test Method ASTM D1557-78.

C. Aggregate Base:

Aggregate base shall be spread and compacted in conformance with Standard Specifications Section 26 for Class 2 Aggregate Base. Finished aggregate base shall have the minimum depth shown and finished grade shall not vary more than 0 . 05 foot above or below the established grade. The aggregate base shall be compacted to a density not less than 95 percent of that obtained in the laboratory according to test Method ASTM D1557-78.

D. Prime Coat:

Apply prime coat at an approximate total rate of O. 25 gallons per square yard to all areas receiving asphalt concrete. Conform to Section 39 of Standard Specifications.

E. Tack Coat:

Apply a "tack to be placed. square yard.

F. Seal Coat:

coat" to all vertical faces, against which asphalt concrete is Apply at a rate of from 0. 02 gallon to 0 .10 gallon per

Conform to Section 39 of Standard Specifications.

Seal coat shall be diluted with an equal amount of water and applied at the rate of 0 .10 gallon of the diluted emulsion per square yard of surface. The surface shall be free of dust and loose material prior to application.

G. Asphalt Concrete:

Asphalt concrete shall be spread and compacted on the prepared base in conformance with the lines, grades and dimensions shown on the drawing and as specified in Section 39 of the Standard Specifications. In addition to the compaction requirements described in section 39 of the Standard Specifications, each layer of asphaltic concrete (surface or base) shall be compacted to a density no less than 95 percent of that obtained in the laboratory according to ASTM Test Method D 2041-69.

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H. Improper Workmanship:

Cracks, settling of surface, improper dtsinage and sloppy connection to previously laid sutfaces will be consttued as impmpet wol'kmanship and will not be acceptable.

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gmw.conservation.ca.gov€¦ · 16/09/1985 · COUNTI OF ALAMEDA PUBLIC WORKS AGENCY 399 Elmhurst...

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Transcript of gmw.conservation.ca.gov€¦ · 16/09/1985 · COUNTI OF ALAMEDA PUBLIC WORKS AGENCY 399 Elmhurst...