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I.OMATERHL AI\ID WORKMANSHIP :

The work shall be carried out in accordance with the Raj PWD (B&R)

specification and explanatory notes forbuilding and house drainage with up to date

correction slips, if any, as per IS 456 & 3370 upto date amendments & as per

sounds *gi;r..i"g practice as decided by the Engineer in charge' The general

arrangeme,lrt of the piping qstem shall be as p€r prevailing practice in the

dePartrnent

2"OCTVrc WORKS :

2.l General :

Some of the important IS codes to be referred during execution of the work are as

follows:

Eqrthwo*IS: 3764 - Safety code for excavationworts

IS: 3720 - Methods of tests for soils

Concrete Works

IS:280.Mildsteelwireforge,lreral@gine€ringpurposes

15:269 - Portland ceme'nt

IS:383 - Comse and fine aggregate

IS:432 - Medium tension steel bars and hard drawn stecl wire

13:516-Methodsoftestingforsftengthofconcrete."

IS:llgg.Methodofsamplingandanalysisofconcrete

IS : 1 566- Fabric reinforce'melrt

6:1786 - Cold twisted steel bars for concrete reinforcement

13:2062 - Stucttral steel

15:2386-Methodsoftestsforaggregatesofconcrete

IS:2502- code of practice for bending and fixing of bars for concrete

reinforcement

13:7861- Recomme,nded practice forhot weather eoncreting (PaIt - I)

IS:4082- Recommendation on stacking and storage of conskuction material

on site.

13:456 - Code of practice for plain and reinforced concrete

IS:3370-Code of practice for concrete structures for the storage of liquids

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Detailed Design :Geri€ral

Configrnation

The design of RCC Elevated

following confi guration -Service Reservoir shall be carried out with the

The dded ddtg *ructrat design and drawings (including reinforcement

d€diqB d br beDding schedule) shall have to prepared taking provisions ofdd lr4 u&r load, Iive loa{ seismic load, wind load, point loads due to pipes

t d tall be checked for most critical condition resulting for various load

cdrinaios. The design shall be based on no crack basis for water retaining

@Epooents.

The oontractor shall be fufly responsible for structural safety, stability & watertigfotness of the stnrcture.

Tweof tank IntzCaoaciW 60 KLStasins 18mDepth of foundation 3 Mtr or more as per

desien/SBCSafe bearine capacity of soil l0 T/somTrme of stagins column &bracinsFreeboard 200 mmStaircase widtlU tead, rise 9O0225-250,

150-175 mrh reso.Size of inletoioe 100 rnmSize of outlet oioe 100 mmSize of overflow oire 100 mniSize of washoutoioe 100 rlm

- Stagng is defined as the difference of levels b"ry"* the finished ground level and

bottom of the water retaining stnrcture (top of the bottomring beam) \

Freeboard shall be considered from thebottom of top dome ringbeam.

Important IS Codes

15:456 - Code of practice for plain and reinforced concrete

IS:337GCode ofpractice for concrete stnrctures for the storage of liquids

IS:875 -Code ofpractice for stnrctural safety ofbuildings,loading standards

IS:1911 - Dead loads

IS:1893 - Criteria for earthquake resistant design and stucture

IS:2970 - Design of raft

IS:11089-Code of practice for design and construction of ring foundation

IS:11682-Criteria for design of RCC staging for overhead wdter tanks

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Ce,ment concrrete ( plain or reinforced ) shall comply with .the rquirement ofspecificdim of R4iasfr*" PWD (B&R) Specification and Eirplanatory Notes forMiDg oal IIfise hainage except in so far as these are not altered or modifiedbyryecific stiddions as give,n in the specifications herein. The concrete grades tobeusod shall notbe leaner than followings :

Concrete thickness

dime,nsions of the RCC components shall not be ress than the

Alt strctures (Foundation, co-lumn, beams of foundation and I rurzs

top ring beam, conical wall, bottom domg balcony, vertical

wall, top dome, stair case etc. Complete

Note:-

- 1. In any case concre-te -i"SH,h* M-zsshall not be used.

2. The concrete mir strall be design mi*.

3. orilinary portland ce,me,nt (oPc) gade 43 confirming to ls 2692 - 1976

shall onlybeused.

Thickness of top dome 100mm

Thickness of bottom dome 125mm

fniitness of ptatfornns, landings l50mm

Thicknes of Water retaining walls, slabs <4m 150mm

Thickness of Water retaining walls, slabs >4m 200mm

Thickness of Ottrer stnrctural walls (load bearing) 200mm

Thickness ofNon stnrctural walls l50mm

Thickness of lean concretebelow foundation 150mm

No of columns 6 ormore

Theminirnmn dcroverofreinforce,mentbars shafl be as following :

In ca* of dry mrfrs (shaft, platforms, foundation) 25 mm

h crse of oqsionally wetted surfaces 6oo0 30 mm

In case ofpermanently wetted surfaces (walls and bottom ofIte water chanrber, central access shaft, platform in the resenroir);reinforceme,lrt dia up to 20mm

35 mm

do- reinforcernent dia above 20mm 40mm

Loads

Account shall be take,a of all loads due to dead loads, live loads, wind loads,seismic loads, water pressure, soil presstre and point loads caused duringinstallation of pipes etc.

The live load for top dome shall be taken as 1.70 KN / sqm .The platforrrs andstairs shall be designed for a live load of 3.00KN/sqm in addition to other loads.

Full water depth including free board and dead storage shall be considered forstnrctural design of the tank.

The area is situated in seismic zone and the seismic load shall be takenaccordingly

The wind load shall be taken assrmring a basic wind speed of 47 rnlsec.

Design Considerations

I Age factor shall notbe more than l(one)

2 The design should be based on elastic theory.

3 In view of tmcertain patte,rn of loading (imposed load) on top dome, allowablemaximurn permissible stesses shall be resfricted to Z}yoof provision in BISfornormal conditions.

4 Tank portion should be designed using mernbrane theory and it should bechecked & corrected for continuity analysis for the stress calculation.

5 In vertical wall reinforcement should be provided in two layers.

6 For computing wind load terrain category 2 artd class B stnrctures shall beconsidered . -:'.

Minimum reduction factor for circular shape shall be taken 0.7.

The ESR is importanl structure hence risk coefficient while taking wind loadshall be accordingly.

Average shear per column shall be calculated as per prevailing formula i"e. (2*Total shear)/number of columns.

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10 Minimum uea of aiffiroem* in columns shall be 0.8% of cross sectional

area of olm ffilly povideit

As wid/eillh quake ue basic load on brace. while designing brace no increase

fudbe elbwcal over permissible stresses

kaeSouldbe designedusing steel beam theory

psl malring rigid joint at junction of brace and column, provision ofddidonal reinforce,me,lrt should be made and customary haunches shall !eprovided

while designing stagng live load on tank part should not be reduced for local

calculations in structural design.

The raft foundation shall be without annular hole.

2.3 Testing of MaterialThe contractor shall make the arrange, ent for testing of material as per relevant IS

codes, PWD specifications and as per direction of Engineer in charge. All the cost

for testing ofmaterial shall be borne by the contractor.

3.0 CI PUDDLE COLLARS: -The size of CI puddle collars shall be according to the size of diffoent pipes (inlet,

outlet, overflow and washout) The minimum lengttr of puddle collar shall be300mm. There should be 3 flanges in 1 puddle collar on both e,nds and in themiddle. The middle flange shall be blind.

The material and holes shall be as per relevant 1

CI DOUBLE F'LAI{GED PIPESThe contastor has to supply the CI double flange pipes for inle! outlet, overflow andwashout as per specifications mentioned in relevant ISS amended up to date for whichthere will be no exta payne,lrt will be gtven by the departnent.

4.0 RAILINGHand railing around the platfonns, Balcony, stairs and landings shall be consisting

of 25mm diameter mdium B class GI pipes in trvo rows (one at the top and otherat middle level) and 1000mm high vertical post 65x65x6 mm angle iron @1500mm centre to cenke (At least two vertical angles are to be provided wherever

distance is less) with all accessories like elbows, tees etc. including wel{ing,threading and.erubedding in ce,ment concqete floor..Railing shali be protected

against corrosion after welding. The pipe shall pass through hole in the vertioal

angle.

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*UJfl. ,#H;qrn vide' oadc rry of somm x 50mm x 6mm Ys' *erq iron and

?So,,.lirs- bG udahal d 3mmm c/c shall be provided outside'from the balcony

otafuBhp(ilmetobottomdomeinthecontainer.MScageshallalsobeprilhil m lhc ladd€r from balcony to top dome'

5I*'ft'3'Cr,AlrP :-lfudrrrrpshatlbe6mmthick50mmwideMSflatfixedoflpipe&colrrmn.

TIMAN EOLE COVER :-

SErue man hole 750x750mm shall be provided' The cover shall be made of 3 mm

thick MS flat. The frame shall be made of MS angle 80x80x4' Tho cover snau f1

connec,ted to this frmre by using two nos. stnrng hinges'

8.0 YENTILATOR:-ThisshallbeT50mmdiaMscowl,4T0mmhighwithmosquitoproofjalishallbefixed atthe toP'

9.0 MS GATE :-TheMsgateshallbeprovidedinfullwittthofstaircase.Thegateshallbeoftwoleafs & shall be made of MS angle 5ox50x6 mm' The 20 mm MS round bars strall

be placed vertically in the gate. The heigtrt of gate at least 1'20 mt' one leaf of

gate can be hinged in column by providing suitable l'ugs while other leaf shall be

hinged in a angle iron post not less than 65x65x6 mm size'

10.0 WATER LEVEL INDICATOR :-

Water level indicator consisting of an approved GI float moving in AC pipe, as

pipe shall be fixed to columnbyMS clamp and iron counte'f weigh and connected

by standard steel flexible wire 4mm thick passing over aluminium pulleys 70mm

dia shall have to be provided. The pulleys shall be propedy fixed in concrete and

should have g,ride'so ihat the wire does not slip from the pulley'

ThescaleshallbecalibratedincelrtimehesandshouldconsistofM.S.sheet20gaugefixedoverwoodenplaokwithanM.S.angleironframeof35mmx35nunx5mrrandpaintedwithwhitee,lramelbase,lettersinblackandred.Thescaleshallbe located and fixed with RCC column at 8m above the ground level '

11.0 MS NUT BOLTS :

Nut bolts shall be of mild steel & of best quality' Bolt shau be of adequate size &

length. The contactor shall provide all holding down' alignment/levelling bolts

required to fix the pipes & specials for ESR'

12.0 PAINTING :

l2.lMetallic Surface . ..1-t -

Ifnototherwisestatedmetallicsurfacesshallreceiveoneinitialcoatatthemanufacturer's workshop. After arrival of the equipment on site' the same *'1:"inspected and damaged portions shall be cleaned and grven'the primer and under

coat gf similar paint After erection all metal work (including railing, gate, clamp,

ladder, manhole oorrr, ventildor etc.) shall be painted with one coat of red oxide,

two rmder cocB ud re finishing cOat of an approved e'namel paint (ICI Ltd;

Ieom&IS&olmLtil, British Paints Ltd., Asian Paints Ltd., Goodlass Nerolac

t1il., Doffi, Shlimr, Steelguard, PolycoaQ.

l2Slldder inside the tank :

Tb ladder inside the tank shall be painted with two coat of epoxy paint on one

ooat e,poxyprimer.

123 Underground concrete surface !

All gnderground RCC surfaces shall be painted with two coats of ISI make

bituminous paint The painting shall be done as recomme,lrded by manufacturer &

relwant IS code.

12.4 Visible concrete surface :

All visible concrete surfaces shall be painted with two or three coats of snol\rcem

of approved make & shade.

12.5 Slogan & logo:The contractor shall paint a area of 6m x 3m on the vertical wall of the tank potion

by using 3 coats of plastic e,rnulsion paint of shade as approved by engineer in

charge to form a base for writing the slogans as directed by Engineerln-charge.

For writing the slogan the letters shall be of 30 qn size. The shade for painting the

slogan will be approved by Engineer in Charge.

13.0 GASKET :

Gasket shall be ofnrbber & as per IS 11149

14.0 LIGHTENING ARRESTER :

Liglrtring arrester shall be of aluminum bar of 25mm dia to be provided at the top

of ESR. This is to be comiected by a GI sfrip of 25 rnm wide & 3mm thick. This

conductor sfiip shall be connected to a 470 illmx 450mm x 3mm thick copper

plate to be e,nrbedded below the average growrd level by digging a pit in drawing.

The earthing syste,nr shall comply with Indian Electicity Rules and shall confirrr

to IS 3M3. The pit shall be refilled by alternate layers of salt and coke as required

and balance shall be filld with loose soil. The 40 mm dia GI watering pipe shall

be provide.d in the pit. Care shall be taken that earth pit does not sink.

5.0 FIXING OF CI PIPES & SPECHLS t . . ..-a --. o- --.^^rAlltheCID/FprpesroquilEdf6fillingofinlet,outletov€rflow&washoutshall**rvertical&ftG.linpropermanner-Allthespecials&pipesshallfixedbyIned'lt of lrfft dtok & rubb€r gasket. The pipes shall be prop€rly clarrped to

ooMdESR- All fiting should b€ reak proof. The puddre collars shall be fixeal

iro'bffi itme d the time of casting. A cI beil mouth shall be fixed on the top

didct&overflowpipeforsrnoothflow.ThebellmouthofoverflowpipeshallbeftGd truly at FSL. The outlet pipe shall be fixed tnrly at top of dead storage' The

wa$out pipe shall be fixed in such a position that the tank should be got

completely dry by opening the washout valve, for this purpose if slope at the

jrmctionofbottomdome&ringbeamisneededshallbemadebythecontractor

with PCC. At the bottom of duck foot bends Pcc bl0cks in M-15 mix shall be

constructed.Allthedoubleflangedpipesshallbeextendeduptominimrrmlengthof 10 m. inhorizontal direction

JP-\JLI

Execrrti've Engineer

PHED DistictRural Div., Ajmer

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