Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

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“The Right to Information, The Right to Live”

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“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 11385 (2008): Subsurface exploration for canals andcross drainage works - Code of practice [WRD 5: GelogicalInvestigation and Subsurface Exploration]

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IS11385:2008

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Indian Standard

SUBSURFACE EXPLORATION FOR CANALS ANDCROSS DRAINAGE WORKS — CODE OF PRACTICE

(First Revision )

ICS 93.020

0 BIS 2008

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

November 2008 Price Group 4

———. .... . .. . ..-( ,..,.. ——. . . . . .

Geological Investigations and Subsurface Exploration Sectional Committee, WRD 05

FOREWORD

This Indian Standard (First Revision) was adopted by the Bureau of Indian Standards,after the draft finalized by the Geological Investigations and Subsurface Exploration Sectional Committeehad been approved by the Water Resources Division Council.

‘Ilis standard was published in 1985. The present revision is proposed to reflect the experience gained on thesubject since then.

[n India, canal systems have been constructed since historic times. With the improvement of the techniquesof construction of canals and cross drainage structures, the necessity of detailed soil investigations are felt,before taking up the actual construction. To prevent loss of valuable water through the canal bed and bankspassing through alluvial or fissury reaches, costly protection works, such as lining, etc, have to be provided. -Reaches are to be avoided where damages can occur to the surrounding cultivated lands, due to waterlogging. Canal embankments often get breached and flood vast areas, if not properly designed. Therefore,adequate subsurface exploration is needed before the canal system is designed and constructed. Similarly, toconstruct a big aqueduct or syphon across a canal, detailed foundation investigations are required, for thesafety of these structures.

Subsurface explorations, therefore, form a very important part in the planning and designing of canals andcross drainage structures. The term subsurface exploration as used herein covers all types of explorationconnected with determination of the nature and extent of the soil and/or rock along the alignment of theproposed canal and its distributaries and also the foundation condition at the sites of the proposed crossdrainage structures. It is not possible to lay down the required extent of exploration to cover all types ofcases. The standard provides guidelines for planning the exploratory works through various stages of theproject development. These recommendations may have to be modified for individual cases, depending uponthe site conditions and other characteristics peculiar to each of them.

[t has been assumed in the formulation of this standard that the execution of its provisions is entrusted toappropriately qualified and experienced people, for whose guidance it has been formulated.

For the purpose of deciding whether a particular requirement of this standard is complied with, the final value,observed or calculated, expressing the result of a test, shall be rounded off in accordance with IS 2: 1960‘Rules for rounding off numerical values (revised)’. The number of significant places retained in the roundedoff value should be the same as that of the specified value in this standard.

, 1, , ..- .-.. !-...——— .—— —— —.. . . . . --— - -.-..———

IS 11385:2008Ill

Indian Standard

SUBSURFACE EXPLORATION FOR CANALS ANDCROSS DRAINAGE WORKS — CODE OF PRACTICE

(First Revision )

1 SCOPE

“rhis standard provides guidance on the type, extentand details of subsurface explorations needed inconnection with the following items of work:

a) Canals — Stability of banks and bed in:

b)

c)

d)

e)

1) cutting, and2) tilling.

Canals — Water loss due to seepage andwater logging in the command area.

Canals — Selection of lining with referenceto the characteristics of bed material,permeability, subsoil water table and salinity.

Cross drainage structures — Design andconstruction of the foundation for headregulators, cross-regulators, drops or falls,super passages, syphons, aqueducts, levelcrossings and bridges.

Borrow area investigations for the suitabilityof material to be used for canal embankmentsand necessary compaction procedure.

2 REFERENCES

The standards listed below contain provisions whichthrough reference in this text constitute provisionsof this standard. At the time of publication, theeditions indicated were valid. All standards aresubject to revision and parties to agreements basedon these standards are encouraged to investigatethe possibility of applying the most recent editionsof the standards indicated below :

IS No. Title

1498:1970 Classification and identificationof soils for general engineeringpurposes (first revision)

i892: 1979 Code of practice for subsurfaceinvestigations for foundations(first revision)

1888:1982 Method of load test on soils

2131:1981 Method for standard penetrationtest for soils @-st revision)

1S No.

2720

(Part 1): 1983

(Part 2): 1973

(Part 5): 1985

(Part 7): 1980

(Part

(Part

3): 1986

4): 1983

(Part21):

(Part 28) :

4078:1980

4434:1978

4453:1980

4464:1985

4%8

977

974

(Part 1): 1976

Title

Method test for soils:

Preparation of dry soil samplesfor various tests (secondrevision)

Determination of water content(second revision)

Determination of liquid andplastic limit (second revision)

Determination of water content-dry density relation using lightcompaction (second revision)

Direct shear test (secondrevision)

Determination of density index(relative density) ofcohesionless soils (firstrevision)

Determination of total solublesolids @t revision)

Determination of dry density ofsoils inplace, by the sandreplacement method (firslrevision)

Code of practice for indexing andstorage of drill cores (firstrevision)

Code of practice for in-situ vaneshear test for soils (secondrevision)

Code of practice for subsurfaceexploration by pits, trenches,drifts and shafis @st revision)

Code of practice for presentationof drilling information and coredescription in foundationinvestigation (first revision)

Method for subsurface soundingfor soils :

Dynamic method using 50 mmcone without betonity slurry (firstrevision)

*

1

IS 11385:2008

1S No.

(Part 2): 1976

(Part 3): 1976

5529

(Part 1): 1985

(Part 2): 2006

6403:1981

6926:1996

7422

(Part 1): 1974

(Part 2): 1974

(Part 3): 1974

(Part4): 1985

(Part 5): 1992

9214:1979

15662:2006

15686:2006

Title

Dynamic method using cone andbentonite slurry (@z revision)

Static one penetration test (@3(revision)

Code of practice or in-situpermeability test:

Test in overburden (firstrevision)

Tests in bedrock (secondrevision)

Code of practice fordetermination of bearing capacityof shallow foundations (firstrevision)

Diamond core drilling — Siteinvestigation for river valleyprojects — Code of practice (firstrevision)

Symbols and abbreviations foruse in geological maps, sectionsand subsurface exploratory logs:

Abbreviations

Igneous rocks

Sedimentary rocks

Metamorphic rocks

Line symbols for formationcontacts and structural features

Method for determination ofmodules ofsubgrade reaction (k-value) of soils in the field

Recommendations forpreparation of geological andgeotechnical maps for river valleyprojects

Recommendations forpreparation of geological andgeotechnical maps for river valleyprojects

3 GENERAL CONDITIONS

3.1 All subsurface explorations should be precededby geological mapping on scales as given in 1S 15686,covering 100 m on either side.

3.2 The type and extent of exploration should be

commensurate with the size and importance of theproject and will depend upon the size of canal systemor the cross drainage structure. This should beneither too little, resulting in inadequate data, nortoo much, resulting in excessive cost and time.

3.3 Subsurface explorations in connection with acanal would cover suitable alternative alignments forthe main canal and its distributaries and will be carriedout to a specified depth, preferably up to a few metresbelow the proposed bed of the canal. In case of crossdrainage structures, the exploration should coveralso, the alternative suitable sites and up to thecritical depth below the proposed bottom of thefoundation. A complete programme of explorationshould be able to give information regarding thefollowing aspects:

a) Canals and distributaries

1)

2)

3)

4)

5)

Shearing properties, that is, cohesion andangle of internal friction of the bed andbank material;

In-situ moisture content and density ofthe bank and bed material;

Seepage characteristics or permeability ofbed and bank material;

Chemical test on ground water;

Ground water table, both in dry andmonsoon season, along the alignment;and

6) Grain size distribution of the material at thebed for calculating the critical velocityand rugosity of the canal.

b) Cross drainage structures

1)

2)

3)

4)

5)

Cohesion, angle of internal friction anddensity of the material up to critical depthbelow the proposed foundation level;

Bearing capacity of the soil or rock at theproposed foundation level;

Ground water table at the site of theproposed structures;

Possibility of liquefaction, if any, of thesandy material in foundation, underseismic condition; and

Silt factor for assessing scour depth.

4 STAGES OF EXPLORATION

4.1 The extent of foundation exploration required

L

IS 11385:2008 hfor a canal or a cross drainage structure of given sizevaries greatly from site to site, depending on thesubsurface conditions and cannot be adequatelyvisualized in advance. The exploration generallyproceeds in stages, the details of each stage growingout of the one before.

4.2 Explorations can be, however, generally sub-di vialed into four stages as given in 4.2.1 to 4.2.4.

4.2.1 Reconnaissance or Prefeasibility Stage

This shall comprise of selection of suitable alternativealignments of the canal and suitable alternative sitesi-orthe cross drainage works on the basis of regionaland local geology, relative impermeability of the area,::conomy of excavation and filling and foundationconditions. The geophysical methods forinvestigations during the reconnaissance stage maybe deployed to assess the thickness of overburdeni].~d bedrock configuration on various alternativesunder consideration. The investigations in this stagewill consist of a general field inspection by a qualifiedtrrgineering geologist and an engineer, for~~ssessment of the overall aspects of feasibility,economy and safety. On the basis of informationgathered at this stage and evaluations made aboutthe expected seepage in the canal, cost of excavationand filling, type and cost of foundation of crossdrainage structures, etc, planning of the detail fieldwork will be made.

4.2.2 Preliminary lnvestiga~ion or Feasibility Stage

4.2.2.1 Objectives, ~pes and methods of exploration

During this stage, certain essential data regardingthe canal and cross drainage structures would becollected. The coverage of exploration should beadequate for examination of the feasibility, whichincludes estimation of the cost, expected seepagelosses in the canal and stability of canal banks andcross drainage structures. This stage would alsoinclude studies for preliminary choice of the canalalignment, selection of the type of lining and thechoice of the type and depth of foundation for thecross drainage structures. The stage of explorati~nwill include the following methods:

a) Exploration by test pits; and

b) Exploration by augering/drilling.

4.2.3 Detailed Investigation or Detailed Pr~jectReport (DPR) Stage

4.2.3.1 In this stage of investigation, the datarequired for detailed design and preparation ofconstruction drawings should be collected. Closecoordination is essential between work of theorganizations for exploration, geology design and

construction. The design engineer and the geologistshould be closely associated with the explorationand they should be required to prepare an outline ofthe scope and extent of exploration.

4.2.3.2 Investigations at this stage would comprisethe following:

a)

b)

c)

d)

Intensive exploration for specific difficultreaches of the canal, where the banks needspecial protection against land slides, r

breaches, water logging, seepage, etc.

Additional drillings of the foundation of thecross drainage structures, to determine theactual condition of the foundation of each andevery component of the structures. Thepossibility of high submergence, sudden ●

drawdown of the embankments, seismiceffects, etc, have to be kept in mind at thisstage.

Ascertaining the relative merits and demeritsbetween the open foundation and well, raft orpile foundation under the piers and abutmentsspecial field shear tests may be used,wherever necessary.

Compaction methods to be determined forcanals in filling, from the reach by reachborrow material testing.

4.2.3.3 The engineer-in-charge slfould be consulted*

to get an idea of the type of foundation that waslikely to be provided at a later stage and accordinglythe depth of exploration should be fixed. The stageof exploration will include the following methods:

a)

b)

c)

Determination of the depth of water table, *

evaluation of field permeability anddetermination of salinity of the ground;

Field penetration and field density tests atthe sites of the foundation of the crossdrainage structures and along the alignmentof the canal; and

Laboratory tests on the disturbed andundisturbed samples for the determination ofengineering properties of the canal bed andbank material, borrow materials forembankment and proposed foundationmaterial of the cross drainage structures.

4.2.3.4 Choice of methods

Normally, for canals and cross drainage structuresof moderate size, exploration by trial pits and drill orauger holes would be sufficient. Some field tests ofpermeability and penetration would also benecessary.

3

II Iili I I ....~. —.. -——. — ..— . . . . ..-. —.

IS 11385:2008

4.2.3.5 Spacing

For canals, exploration by pits at spacing of 500 mdepending upon the nature of the soil may benecessary. However, wherever there is an apparentchange of characteristics, the pits may be dug ateven 200 m to 300 m spacing or closer, if required.Under the major cross drainage structures the holesor pits should be selected at specific points, wherethe proposed piers, wells and abutments are to berested.

4.2.3.6 Location

Explorative holes and pits should follow the centralline of the proposed canal alignment and also theaxis of the cross drainage structures.

4.2.3.7 Depth of exploration

a)

b]

4.2.4

In case of canals, exploration should reach atleast 3 m below the proposed bed of the canal.If the canal is to be in a rocky reach, this depthmay be reduced at the discretion of theengineer-in-charge. If the strata appear to bechanging, the depth of exploration should goup to an extent of canal depth below the bedlevel.

In case of cross drainage structures, the depthof the holes or pits should be up to the bottomof the expected bulb of pressure under theabutments or the piers or down to the hardfirm strata or rock, if available. In case of wellfoundations, however, the depth ofexploration should reach the stable strata,which can support the foundation safely (see1s4453).

Construction Stage

Construction stage exploration should aim at makingavailable data generally, for the evolution of specificfoundation problems and preparation of thefoundation after excavation and special precautionsto be taken along the canal as and when the projectis under actual execution.

5 METHODS OF EXPLORATION

5. t The following categories of methods may beused for subsurface exploration for canals and crossdrainage works:

a) Trial pits,

b) Borings ( auger boring and core drilling),

c) Field tests in-situ, and

d) Geophysical methods.

6 EXPLORATION BY PITS

6.1 Shallow or deep trial pits maybe used, accordingto the size of the canal, to investigate the engineeringproperties of the material, salinity of the ground,water table, seepage rate, etc, along the canalalignment. Similar investigation may be performed atthe proposed foundation of the cross drainagestructures of minor nature.

6.2 At the surface near the pit, the excavated materialshall be placed in an orderly manner around the pitand marked stakes shall be driven to indicate depthof pit from which the material is removed, in order tofacilitate logging and sampling.

6.3 The level of the water table and the level,location and rate of seepage flow in the test pitshould be recorded date wise.

7 EXPLORATION BY BORINGS

7.1 Borings provide the simplest method ofsubsurface investigation and sampling. They maybe used to indicate the subsurface strata and tocollect samples from each of the strata.

7.2 Borings may be made by several methodsdepending upon the importance of the work and onthe nature of the sub-soil strata. They are as below:

S1 No. For SoiIs For Rocks

(1) (2) (3)

i) Post hole auger Bore drillingii) Shell and auger (see IS 6926)

boring Short drilling(see IS 1892) (see IS 1892)

iii) Wash boring(see IS 1892)

iv) Rotary drilling(see IS 1892)

7.3 Auger Boring

7.3.1 Post Hole Auger

Hand operated post hole augers 100 mm to 300 mmin diameter may be used for exploration up to about6 m. However, with the aid of tripod, holes for greaterdepths can be excavated. Depth of augerinvestigations is limited by ground water table andalso by the presence of gravels and boulders.

7.3.1.1 Mechanically operated augers are alsoavailable and may be used in case of deep borings indifficult strata.

7.3.1.2 An auger boring is made by tuning the augerto desired depths into the soil, withdrawing it andremoving the soil for examining and sampling. Theauger is inserted in the hole again and the process is

4

repeated. Holes are usually bored without additionof water in loose, moderately cohesive moist sand.But in hard dry soils or cohesion less sands theintroduction of a small amount of water into the holewill very much facilitate the drilling and sampleextract ion.

7.3.2 Shell and Auger Borings

Pipe casing or shell is required in unstable soil, inwhich the bore hole collapses and especially wherethe boring is extended below the ground water level.Stabilisation of the hole, by means of bentonite slurry,can also be done. The inside diameter of the casingshould be slightly larger than the diameter of theauger used. Boring up to 200 mm dia and 25 m depthcan be done with manual operation. The casing isdriven to a depth not greater than the top of the nextsample and is cleaned out by means of the auger.

7.4 Core Drilling

7.4.1 Core drilling should be done in accordancewith IS 6926.

7.4.2 The accuracy and dependability of the recordsfurnished by diamond drilling depend largely uponthe size of the core in relation to the kind of materialdrilled, the percentage of core recovery andexperience of the drill crew. Recovery of core is muchmore important than the rapid progress in drillingthe hole, When drilling in soft materials, the watercirculation should be reduced or stopped entirelyand the core recovered ‘dry’.

7.4.3 Detailed history of mechanical operation ofdrilling including observations on the loss ofreturned water and its reappearance, difficultiesencountered should be included in the drilling report.

7.4.4 Percolation tests under specified pressuremay be done in drill holes, if needed, using packersas the drilling progresses.

8 FIELD TESTS

8.1 Field tests (in-situ) are those in which material istested without actual removal of the material from itsexisting position. Those applicable to stability ofcanal banks and foundation of cross drainage,structure are the following:

a) Strength tests

1) Penetration tests; and2) Shear tests.

b) Measurement of density of foundationmaterial.

c) Permeability tests.

d)

e)

IS 11385:2008

Determination of modulus of subgradereact ion(k-value) of soils in field asindicated in IS 9214.

Determination of safe bearing capacity byplate load test as per 1S 1888.

3.1.1 The necessity and the number of each type oflest to be conducted, depend on the type of materialmd its degree of variability.

B.2 Strength Tests

B.2. 1 Penetration Tests

8.2.1.1 These tests [see IS 2131, IS 4968 (Part 1 ),IS 4968 (Part 2) and 1S 4968 (Part 3)] consist ofmeasuring the resistance to penetration under staticor dynamic loading of different shaped tools. Thetests are empirical and have been developed fromexperience. They should be performed carefully inthe prescribed manner.

8.2.1.2 Static and dynamic penetration tests providesimple means of comparing the results of differentbore holes on the same site and for obtaining anindication of the bearing value of the soils and ofthe state of densification of non-cohesive soils. Co-rrelation between the number of blows obtained instandard (dynamic) penetration tests with relativedensity of non-cohesive soils and consistency ofsoil (that is, soft, medium, stiff, etc ) in cohesive soil(see IS213 1) and between penetration resistance instatic penetration tests with bearing capacity andrelative density of non-cohesive soils are given inseveral publications (see also IS 6403).

8.2.1.3 The number of tests should be fairly large tocover the entire critical foundation area.

8.2.2 Shear Tests

These tests (see IS 4434) measure the in-situ strengthof cohesive soils, which are too soft or sensitive forsampling.

8.3 Permeability Tests

8.3.1 Permeability ofa soil gives the measure of therate, by which water can flow through unit area of itunder unit hydraulic gradient. Knowledge of thepermeability of the soil is necessary in estimatingseepage through the canal banks in permeable soilsor fksured rock and in determining the type andnecessity of lining the canal.

8.3.2 Permeability is usually determined by in-situpumping in and pumping out tests [see IS 5529(Part 1) and IS 5529 ( Part 2 )] in holes or wells. Thistest is very important where loss of water from thecanal is not at all desirable and also where it maycause water logging in the neighborhood.

5

IS 11385:2008

8.4 Measurement of Density of Foundation Material

8.4.1 In-situ density of canal banks and offoundation material is used in stability analysis. Italso offers information on the state of compactionand to decide whether further compaction is needed.

8.4.2 The sand density method is used to determinethe in-place density by excavating a hole from ahorizontal surface, weighing the material excavatedand determining the volume of the hole by fillinr, itwith calibrated sand [see IS 2720 ( Part 28 )]. Thewater content [see IS 2720 (Part 2)] of the soil at thepiace of determination of in-situ density is neededto calculate the dry density of the soil. Othermethods, such as core cutter method and surfacenuclear gauge may be used.

8.4.3 This test is applicable to very shallow dep?hsonly, or to the depths of pits and trenches, where itis possible to perform the test up to the depthexcavated. The density determination at depthshould be made from undisturbed samples obtainedfrom depths, or by deep penetration tests in non-cohesive soils.

9 SAMPLING

9. I The methods employed for enabling for enablingcollection of samples for visual examination and forperformance of laboratory tests thereon have alreadybeen described in 6 to 8.

9.2 To take undisturbed samples from bore holes,properly designed sampling tools shall be used.These differ for cohesive and non-cohesive soils andfor rocks. Special samplers like piston sar,~plers and/or freezing or grouting techniques may have to beemployed in cases where samples are to be collectedfrom cohesion less sand which cannct be sampledby ordinary equipment and methods, particularlythose existing below ground water level.

9.3 Sufficient quantity of representative undisturbedsamples shall be collected for carrying out thenecessary tests.

9.4 While boring small diameter bore holes infoundation area of cross drainage works or alongthe canal alignment, the total material recovered ascore should be collected and stored in core boxes(see IS 4078 ). Samples of soil and rock should becollected and preserved in sealed bars to retain theirnatural water content. Samples should berepresentative of the material, as it is found in thearea.

9.5 Samples collected in the process of routineexploration are not as a rule satisfactory fordetermination of properties of soil in its natural

condition. For this purpose, undisturbed samplesshould be collected from large diameter bore holes(100 mm to 150 mm diameter minimum), or from theopen pits.

9.5.1 Bore hole samples should be 450 mm to600 mm long and should open pit samples 250 mm to.300 mm cubes. Every effort be made to preservesuch samples as nearly in their natural condition aspossible.

10 EDLAMINATIONAND TESTING OF SAMPLES

10.1 The samples of soils and rocks collected asdescribed in 9 should be examined and tested in thelaboratory, for determining their index andengineering properties. The various tests that areusually necessary are given in 10.2.

10.2 Tests for Soils

10.2.1 Visual and Manual Examination

This would give general description of the soil orrock in terms of colour, consistency, structure, etc,to help in general classification of the material.

10.2.2 Natural Moisture Content

Ithelps in assessment of pore pressure in thefoundation and backfill.

10.2.3 Liquid and Plastic Limits

Liquid and plastic limits are measures of waterabsorption qualities of clay. They give an indicationof the cohesiveness of soil and are also useful insoil classification [ see 1S2720 ( Part 5 )].

10.2.4 Particle Size Distribution

Knowledge of particle size distribution is of use forsoil classification and in understanding its specificfeatures such as density, permeability, etc:

10.2.5 Bulk Density

In case of canal banks and foundation of crossdrainage works, it is essential for computing theirstability.

10.’2.6 Permeability

Knowledge of permeability of the canal banks and ofthe foundation strata of the cross drainage structuresis necessary, for estimating the seepage loss, uplift,grouting requirements, etc.

10.2.7 Consolidation Characteristics

These are required for estimating the magnitude andrate of settlement due to consolidation in the canalbanks and also in the foundation of the crossdrainage structure.

6

IS 11385:2008

10.2.8 Swefling Tests

Swelling tests are useful for clays present in theembankment to assess the likely pressures the ciaywould exert on saturation. These tests should beconducted at the lowest moisture content that maybe obtained in the field.

10.2.9 Strength Characteristics

Strength characteristics of soil maybe determinedby unconfined compression test [see IS 2720(Part l)], direct shear test [see IS 2720 (Part 13)]and triaxial shear test.

10.2.10 Compaction Test

Compaction test may be required for comparison within-situ densities [see 1S 2720 ( Part 7 )] .

10.2.11 Relative Density

For cohesion less soil to assess the degree ofcompaction of the soil in-situ [see 1S 2720 (Part 14)]

10.2.12 Chemical Analysis

Chemical test may be performed on soil samples fromareas suspected to be saline, to determine solublesalt content [see 1S2720 (Part 21)].

11 RECORDING AND REPORTING OF DATA

11.1 General

Information collected from the explorations shouldbe recorded and presented in a systematic mannersuitable for convenient use. The locations of thecanal and crossdrainage structures and points ofexploration should be clearly indicated on a map.Trial pits and different types of bore holes should be

indicated on the location maps using suitablesymbols, in accordance with IS 7422 (Parts 1 to 5).

11.1.1 The scales used for maps should be inaccordance with 1S 15686.

11.2 Logging of Pits and Holes

11.2.1 Location

Every pit and hole should be definitely located on amap by being tied to a co-ordinate grid system. Thetop elevations should also be recorded in the map.

11.2.2 Identification

The holes and pits should all be numbered normallyin the order in which they are drilled and with suitablesymbols, as given in IS 7422.

11.2.3 Logs

A standard and exhaustive log form should be usedgiving as much information as possible ( see IS 4453)and IS 4464.

11.2.4 Description of Soils

The soils should be described in the logs and in therecords according to IS 1498.

11.3 Subsurface Sections in Foundations of CrossDrainage Structures

Sections showing subsurface conditions believed toexist should be prepared. The locations of thesections should be selected in a manner such thatthe information is presented in the best possible way.in the sections, different information like type andnature of subsurface materia!, C, ~ , natural moisturecontent, density, etc, may be shown for the differentstrata.

MGIPF--844 CePU of BIS/08-9-l 2-200&300 BOckS

7

Bureau of Indian Standards

BJS is a statutory institution established under the Bureau ofIndian Standards Act, 1986 to promote harmoniousdevelopment of the activities of standardization, marking and quality certification of goods and attending toconnected matters in the country.

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BIS has the copyright of all its publications. No part of these publications maybe reproduced in any form withoutthe prior permission in writing of BIS. This does not preclude the flee use, in course of implementing the standard,of necessary details, such as symbols and sizes, type or grade designations. Enquiries relating to copyright beaddressed to the Director (Publications), BIS.

Review of Indian Standards

Amendments are issued to standards as the need arises on the basis of comments. Standards are also reviewedperiodically; a standard along with amendments is reafhned when such review indicates that no changes areneeded; if.the review indicates that changes are needed, it is taken up for revision. Users of Indian Standardsshould ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of‘BIS Catalogue’ and ‘Standards: Monthly Additions’.

This Indian Standard has been developed from Dot: No. WRD 05 (455).

Amendments Issued Since Publication

Amendment No. Date of Issue Text Affected

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{

28329295,2832785828327891,28327892

AHMEDABAD. BANGALORE. BHOPAL. BHUBANESHWAR. COIMBATORE. FARIDABAD.GHAZIABAD. GUWAHATI. HYDERABAD. JAIPUR. KANPUR. LUCKNOW. NAGPUR.PARWANOO. PATNA. PUNE. RAJKOT. THIRUVANATHAPURAM. VISAKHAPATNAM.

)%n[ed al the Manager, Govt of India Press, Farldabad

Text1: (Reaffirmed - 2012)