,

IS 6403:1981( Reaffirmed 1997)

i Indian Standard

CODE OF PRACTICE FORDETERMINATION OF BREAKING CAPACITY

OF SHALLOW FOUNDATIONS

( First Revision)

Sixth Reprint FEBRUARY 1998

UK 624.151.5:624.131.52 :006.76

o C’O’oyr;ghf 1981

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

Gr 4 November 1981

●

IS 6403:1981

Indian Standard

CODE OF PRACTICE FORDETERMINATION OF BREAKING CAPACITY

OF SHALLOW FOUNDATIONS

( First Revision)$

Foundation

Chairman

PnoF DXNESH MOHAN

Members

DE R. IL BHAND~RI

Engineering Sectional Committee, BDC 43

Reprinting

Central Building Research Insti! ute ( CSIR ),Roorkee

Central Building Research Institute ( CSIR )Roorkec

CEXXF EN QXNEER Calcutta Port Trust, CalcuttaS rim S. GUHA ( .Mmrndt )

SHRI M. G. DLNDAVATE The Concrete Association of India, BombaySIiRI N. C. DUGQAL ( Alfematc )

DB R. K. DA8 GUPTA Simplex concrete Piles ( India ) Pvt Ltd, CalcuttaADDITIONAL CBIEr ENOINEEE ( Af@mat# )

SHIU A. G. DAETIDMZ In personal capacity ( 5 Hungerfard Road, 121 Hunger-ford Stwrt, Calcutta )

SERX V. C. DEBEPANDE The Pressure Piling Co ( I ) Pvt Ltd, BombayDIRECTOR ( CSMRS ) Central Water Commission, New Delhi

DLCPUTY131 RECTOB( CSMRS ) ( Afhrndt )SHRI A. H. DIVANJI Asia Foundations and Construction Co Pvt Ltd,

BombaySrm~A. N. JANQLE ( Alternate)

DR JAIJDItUI NARAm Indian Gcotechnic Society, New DelhiPrtor SWAMI SARAN ( Akmafc )

SHRI G. S. JLIN G. S. Jain & Associates, RoorkeeSHIt~ ASROX KUmAR JAIN ( Alt.rrrate )

JOINT DIRECTOR ( D ) National Buildings Organisatio,n, New DelbfSHRI SUNIL BEEY ( Alternate )

JO~STM ~DIREOTOR REBEAXCH Ministry of Railways ( RDSO )

‘ JOINT DIRTCCTOBRWIEAROE ( B & S ) ( Altwnatt )

( Con#inucd m Page 2 )

@ Zopyright 1981

BUREAU OF INDIAN STANDARDSThis publication is protected under the Indian Cop~ight Act ( XIV of 1957 ) andreproduction in whole or in part by any means except with written permission of thepublisher shall be deemed to be an infringement of copyright under the said Act.

,

1’5. Contlnutd Jrom piJAI~ I )

,i4tmbers Represmlin~

I}R R. K. KA’r’I’1 Indian Irrstitutc of Tec}mokrgy, Bombay-+Nc1]S. R. KIILKAR~r M, N. Dastur & Co Pvt Ltd, Calcutta

St(Rt S. ROY ( Altcnrate )>I!lii O, P. MA LHOTRA Public Works Department, Chandigarh Administr*-

-tion, Charv+!garh-), IJtf,4 P. M~,rllust Central Warchous,ng Corporation, New Dclhi<,,,<! \’. 1+,,MATHCR Machcnzics Limited, Bombay>IIEI ‘~. ~. D. k[UNSr Engineers India Limited, New Delhi

St+N1 ,M. lYENo Ai2 ( Alternate )]+11[, ohlBIR Sl~OK lingincer-in-Chief ’s Branch, Army Headquarters,

New DelhiMAJ H. K. BRUTANI ( A!t.rnate )

SIII~[ f{. K, PANTHAKY The Hindustan Construction Company Limited,Bombay

SHrzI V. M. MLDQm ( Af(crnatc ):iHR] M. R. PUXJA Ccmindia Co i.tri, Bombay

SR~l S. MUKIIRRJEE ( Afftrrratt )S}{R] ~. E. V. ~A13HVAN The Braithwaite Burn & Jcswp Construction Co Ltd,

Calcutta%I,i[ A. .A. IIAJw Vijayanagar Steel Plant ( St.rl Authority of India ),

New Delhip!c,>F (;,,P,4L~ANJAN Clniv=rsityO( R.oorkee,RoorkeeSlit+[ 1’. Y. !Y!:5BAFiAo Gammon India Limited, Bombay

>t{tt’1S. A, RrJnul ( ,4/twmrtc )\ u RTY. V. NArtASISS~A RACI Bok.ar~ka~~el Plant ( Steel Authority of India ),

!)11 \’. V. S. RAO iNagadi Consultants Pvt Ltd, Nrw DelhisiIni AHJUN RJJHSI~,; NANI Cement Corporation of India. New Delhi

SHR[ ~. S, SItIVA9TAVA ( Affernate )1)R A. SAKGLTNAN College of Engineering, Guindy

S!{BL S. BOrIMtNATnAN ( Af/trrrate IS,IRI K, R. SAXENA Public Works Department, Government of Andhra

Pradesh, HydcrabadI)R S. P SHRIVASTAVA [Jnitcd Technical Consultants Pvt Ltd, Ncw Delhi

r)~ R KAPUR ( ,4ffernafe )S[{]{l .~. slVA. >UltU ?vLnistry of Shipping and Transport, New Delhi

>11Rr 1). V. SIKKA [ Aftwnate )< .7r’~[tl,N,rk:~ul~r3 ENGINEER Central Public Works Department, New Delhi

( DWIIJNS )EXECIITIVW I?NoIN1713R

DIVJTONS ) V ( Af/wnaft ).HI{I hf D. TAM DEKAFt Bombay Port Trust, Bombay[)R ,4. VA HADARAJAN Indian Institute of Technology, Ncw Delhi

[)({ R. KANIBAJ ( Alternate )~Hi{l G. RAMAN, Director General, 1S1 ( Ex-ofi/io Member )

Director ( Civ Engg )

Secretnry

S~Rt K. M. MATIII-RDeputy Dlrcc!or ( Civ Engg ), 1s1

( Confinad on page 16)

2

,

Indian Standard

IS 6403:1981

CODE OF PMCTICE FORDETERhf~ATION OF BREAKING CAPACITY

OF SHALLOW FOUNDATIONS

( First Revision)

O. FOREWORD

0.1 This Indian Standard ( First Revision ) was adopted by the IndianStandards Institution on 30 January 1981, after the draft finalized by theFoundation Engineering Sectional Committee had been approved by theCivil Engineering Division Covncil.

0.2 The bearing capacity of foundations is needed for dimensioning thefoundation for any structure. Several methods are available for thedetermination of bearing capacity of shallow foundations anti thisstandard gives some of the methods which are commonly used for thepurpose. Comparison of the results shows that when each of the variousmethods is applied to different problems no one method consistently giveshigher or lower values of allowable bearing pressure. The designer musttherefore regard the methods as aids to design which cannot replace thecritical role of engineering judgement.

0.2.1 This standard was first published in 1971. The principal modi-fications ‘made in this revision are: (a) keeping its terminology in line withthat of other related Indian Standards, (b) giving’ generalized equationsfor calculation of ultimate bearing capacity, (c) including cone penetra-tion methods and (d) deleting adjustment for fine sand and silt.

0.3 For the purpose of <irciding whether a particular requirement ofthis stmdard is complied with, the final value, observed or calculated,expressing the result of a test or anaiysis, shall be rounded off inaccordance with IS: 2-1960*. The number of significant places retainedin the rounded off value should be the same as that of the specified valuein this standard.

●Rules for rounding off numerical values ( reci$td ).

3

,

I‘s,.

IS 6403:1981

1. SCOPE

1.1 This standard covers the procedure for determining the ultimatebearing capacity and allowable bearing pressure of shallow foundationsbased on shear and allowable settlement criteria.

2. TERMINOLOGY

2.0 For the purpose of this standard, the following definitions shallapply.

2.1 Tersrss Relating to Bearing Capacity

2.1.1 Net Loadinx Intensity — The net loading intensity on the foundationis the gross inttnsity of loading minus the weight of displaced soil above

the foundation b:tse.

2.1.2 lrltimatc Bearing Capacity — The irltensity of loading at the baseof the foundation which would cause sitear failure of the soil support.

2.1.3 Safe Bra ring Capacity — Maxirnunl intensity of loading that thefoundation will safely carry without the risk of shear failure of soilirrespective of any sert!ement that may occur.

2.1.4 Safe B~aring Preswre or Net Soil Pressure for spectjird settlement -

The iiltensity of )oading that will cause a permissible settlement or speci-fied settlement of the structure.

2.1.5 Allowable Bearin~ Capactty — The net intensity of loading whichthe found ati{~rl will carry without undergoing settlement in excess of rhepermissible value for the structure under consideration but not exceedingnet safe bearing capacity.

2.2 General Terms

2.2.1 Dmsip Index ( Relative Density ) — The ratio of the differencebetween the void ratios of cohesionless soil in the loosest state and anygiven state to the difference between its void ratios at the loosest anddensest states.

2.2.2 Efective Surcharge at the Base Level of Foundation — The intensityof vertical pressure at the base level of foundation, computed assumingtotal unit weight for the portion of soil above the water table and sub-merged unit weight for the portion below the water table.

2.2.3 Footing — A structure constructed in brickwork, masonry orconcrete under the base of a wall or column for the purpose of distribut-ing the load over a larger area.

2.2.4 Foundation — That part of a structure which is in direct contactwith so”il and transmits loads into it.

4

IS 6403:1981

2.2.5 Shallow Foundation — A foundation whose width is greater thanits depth. The shearing resistance of the soil in the sides of the found-ation is generally neglected.

3. SYMBOLS

3.1 For the purpose of this code and unless otherwise defined in the text,the following letter symbols shall have the meaning indicated againsteach:

A = Area of footing in cms

A’ =

B =

B’ =

b=c=

q -

c%=

D1 =

Dw =

d=

dc, da, dy =

e=

en =

CL =

H=

ic, ia, iy =

Xa =

L .

L’ =

N-

Effective area of footing in cmz

Width of strip footing, width of footing, sideof square footing, diameter of circular foot-ing in cm

Effective width of footing in cm

Half ‘of B

Cohesion in kgf/cms

Undrained cohesion of the top layer inkgf/cm*

Undrained cohesion of the lower clay layerin kg f/cm3

Depth of foundation in cm

Depth to water table in cm

Depth of top clay layer with undrainedcohesion Cl

Depth factors

Eccentricity of loading in cm

Eccentricity of loading along the width incm

Eccentricity of loading along the length incm

Horizontal component of loading in kgf

Inclination factors

Depth factor ( varies linearly from 1 fordepth Dt = O to 133 for depth Dr = B )

Length of footing in cm

Effective length of footing in cm

Corrected standard penetration value

X., ~’., Na, .iV’a, .Ny, N’y = Bearing capacity factors

5

IS 6403:1981

N~ =- tan’ ( tr14 i- d]2 )

g = Effective surcharge at the base level offoundation in kgf/cms

qa e Net soil pressure for a specified settlementof 25 mm in kg f/cm*

90 = Static cone penetration resistance in kgf/Cms

qu = Net ultimate bearing capacitygeneral shear failure in kgf/cmz

q’~ = Net ultimate bearing capacitylocal shear failure in kgf/cms

R u Relative density of soil

W = ~a~l;ection factor for location

fc, $a, $y = Shape factors

based on

based on

of water

a = Inclination of the load to the vertical indegrees

# == Angle of shearing resistance of soil indegrees

-f = Bulk unit weight of foundation soil kgf/cms

4. GENERAL

4.1 Sufficient number of undisturbed samples, about 40 to 100 mm indiameter or more or block samples should be obtained, where possible.These samples are for the determination of field density of soil andconducting tests for determining the relevant shear and consolidationparameters of the soil. Tests on soils shouId be conducted in accordance

with relevant parts of IS : 2720*.

I4.z Position and fluctuation of water table should be ascertained.

Reference may be made to 1S : 1892-1979t and 1S :2132-1972$ for

guidance regarding investigations and collection of data.

5. ULTIMATE NET BEARING CAPACITY

5.0 General — Three types of faihtre of soil support beneath thefoundations have been recognized, depending upon the deformationsassociated with the load and the extent of development of failure surface.

.—.*Me[hod. of test for soils.Kbdc of practice for subsurface investigations for foundations ( ,fi,II r.oi~ion ).~Code of practice for chin-walled tube sampling of soih ( fird rmision ).

6

IS 6403:1981

They are: a) general shear failure, b) local shear failure and c) punch-ing shear. The choice of which method of analysis is best suited in agiven situation is difficult to make, because only limited test data areavailable on full sized tlxmdations to verify the reliability of the computedbearing capacity. However, guidelines given in relevant clauses may beused for guidance. Wherever possible bearing capacity calculationsshall be made on the basis of shear strengtk parameters # and c obtainedfrom appropriate shear tests [ sw IS :2720 ( Parts XI and XIII)*] orfrom plate load test results as given in IS: M@N81t Oi from staticcone peuetratiou resistance ge obtained from static cone penetration testas given in IS : 4968( Part 111 )-1976$.

5.0.1 Effect of Eccentricity

a)

b)

Single Eccentricity — If the load has an eccentricity e, with respectto the centroid of the foundation in only one direction, then thedimension of the footing in the direction of eccentricity ehall bereduced by a length equal to 2 t. The modi%d dimension shallbe used in the bearing capacity equation and m determining theeffective area of the footing in resisting the load.Double ficentrici~ — If the load has double eccentricity m and en )wit h respect to the centroid of the footing then the effectivedimensions of the fating to be used in determining the bearingcapacity as well as in computing the effective area of the footingin resisting the load shall be determined as given below:

L’=L-2u=

B’=B-2e,

A’ =L’x B’

5.1 Soils with Cohesion and Angle of Shemissg Reeistatmce

5.1.1 The folIowing formulz shall be used for calculating ultimate netbearing capacity in the case of strip footings:

a) In case of general shear failure qa = cJVe + q ( .Na — 1 ) ++BY ~y

b) In case of local shear failure g’a = # c~e + g ( N’a – 1 ) -i-j ByWy

The values of No, Nc, Na, Ng, WY and My may be obtained fromTable 1.

● Methods of testfor soils: Part X1 Determination of shearstrength parametersof● speciroen tested in unconsolidated undrained triaxiat comprcmion without themcuuremeot of pore water pressure, and Part XIII Direct shear test ( Jrrt rmi~n ).

tMcthod of load test on soils ( Jaond rwijwn 1.$Method for subsurface sounding for soiix Part III Static aone penetration test

(Jr$l rm”,ion).

7

IS 6403: 1981

TABLE 1 BEARING CAPACITT FACTORS( CLIIA$85.1. I )

BSARIHO CAFAOITY FAOTOBa~. —.—.—-—-.~ .. ——.— — .. —-

Nc(Dc~ees)

Nq NY

0 5“14 1“00 0’00

5 649 1“57 0,4510 8.35 2’47 1,22

15 10”98 394 2.65

20 14:83 640 5.3925 2072 10”66 108830 3014 1840 224035 4612 !W30 480340 75.31 64”20 109’41

45 13888 13488 271-76

50 266.89 319”07 76F89

NOTIt — For obtaining valuet of N’e, N’q and N’y, calculate # - tan+(0671 an+j. Read Nc, Nq, and NY. from the Tahlc eorrrspnnding to the valueof +’ 1nwcad Of + which are values of N’c, N’q, N’y respectively.

5.1.2 The ultimate net bearing capacity obtained in 5.1.1 for stripfooting shall be modified to take into account, the shape of the footing,inclinatiori of loading, depth of embedment and effect of water table.The modified bearing capacity formula are given as under:

a) [n case of general shear}

= c,VC~edcic + g( .Ng — 1 ) ~adaiafailure qd + ~ BYNy~ydyiy W’

b) In case of local shear ~ = # tNc ICdcic + q( N’a - 1 ) Jadaiafailure g’d ~ + ~ ByN’ysydyiy W’

5.1.2.1 Tbe shape factors shall be as given in Table 2.

%

Oii)

iii)

iv)

TABLE 2 SHAPE FACTORS

sKAPlr Or ~ABE SHAPB FAOTOB~——.A.—A — t

#c $q JY

Continuous strip I’00 I.00 1“00Rcctanr,lc I +02 B/L l+ O”2B/L 1-0-4 B/L

Square 1“3 I “2 0“8Circle 1“3 1.2 06

Uie L?as the diameter in the bearing capacity formula.

5.1.2.2 The depth factors shall be as under:

ii. ===1 + 0-2 Dt/B q~

dq=dy=lfor~<l OO

dq = dy = 1 + 0“1 D1/B~~+ for ~ > 10°

NOTIt — The correction is to be applied only when back filIing is the with proparcompaction.

5.1.2.3 The inclination factor shall be as under:

‘C=’”=(’-%J“=(l--;Y5.1.2.4 E/Jbct of water tabla

a) If the water table .is likely to permanently remain at or below adepth of ( Dr + B ) beneath the ground level surrounding thefooting then W’ == 1.

b) If the water table is located at a depth D! or likely to rise to thebase of the footing or above then the value of W’ shall be takenas 0“5.

c) If the water table is likely to permanently got located at depthD! < Dw < ( Dr -!- B ), then the value of W’ be obtained byllnear interpolation.

5.2 Cohesionless Soil ( c = O ) — The u] timate net bearing capacityshall be calculated as given in 5.2.1 and 5.2.2.

5.2.1 Ba~cd on Relative Density — The formukz given in %1.1 and 5.1.2shall be used, together with relevant shear strength parameter.

5.2.1.1 The relative density as given in Table 3 shall be used asa guide to de[crrnine the method of analysis.

TABLE 3 METHOD OF ANALYSIS BASED ON RELATJVE DENSITY

SL ILE.LATIVEDENSITY VOID CONDXT]ON M~TSSOD ox AX?ALYOISNo. ( DEXa[TY IxTmE ) RATLO

i) C.:eater than 70 percent Less Deasc General shearthan0“55

ii) Less than 20 pcrccnt Greater Lowe Local chear ( as well uthan0.75

punching shear )

iii) 20 to 70 percent 0’55 to Medium Interpolate between0.75 i) and ii)

9

IIS 6403: 1981

5.2.2 Bated an S[andard Penetration Resistance Value — The standard:.:. penetration resistance shall be determined as per IS : 213! -1981 ● at a

number of selected points at intervals of 75 cm in the vertical directionc;r change of strata if it takes place earlier and the average value beneatheach point shall be determined between the level of the base of the foot-ing and the de~th equal to 1“5 to 2 times the width of foundation. Incomputing the average any individual value more than 50 percent greaterthan the average shall be neglected, but the values for all loose seamsshall be included.

5.2.2.1 The ultimate net bearing capacity shall be calculated fromfo]lowing formula ( covering effect of other factors as mentionedin 5.1.2 ):

gd=$’(~q– 1 ) ~Qdqia+ ~ ByNyqdyiy W’

Where # may be read from Fig. 1, Ny, ,Vq may be read fromTable 1, Sa, dQ, iq, syj dy, iy, and W’ may be obtained as in 5.1.

5.2.3 Method Based on Static Cone Penetration Test — The static cone pointresistance ‘gc’ shall be determined as per IS : 4968 ( Part 111 )- 1976t atnumber of selected points at intervals of 10 to 15 cm. The observedvalues shall be corrected for the dead weight of sounding rods. Thenthe average value at each one of the location shall be determined betweenthe level of the base of the footing and the depth equal to 1~ to 2 timesthe width of the footing. The average of the static cone point resistancevalues shall be determined for each one of the location and minimum ofthe average values shall be used in the design. The uitimate bearingcapacity of shallow strip footings on cohesionless soil deposits shall bedetermined from Fig. 2.

[ 5.3 Cohesive Soil ( when + = O )

5.3.1.1 The net ultimate bearing capacity immediately after cons-t~ii..tl(;,, on fairly saturated homogeneous cohesive soils shall be calculatedkmn following formula:

qd = cNe SC dc i=

where

Afc == 5“14.. ..—.—-— ...-— —*fite~ho~(u; sundard penetration test for soils ( jrJf rmijim ).~kfet}i(,d for subsurface sounding for soilw Part 111 Static cone penetration test

: firuxruriltin ).

. ,. .. ..

IS 6403:1981

I

.0

q

\>0

N

om

o“ u

_-— — \ zF- -— -i 0

a

0

\m

_____ 0- a

,1

——~+

i1

__.._]

I ‘ 1-–..+. -.. ~. _

I, 71

28 30 32 3fi 36 38 60 L’2 bb (+6

ANGLE OF INTERNLL FRICTION, C$ (DEGREES)

uuz

;

i%

:

FIG. 1 RELATIONSHIP BETWEEN ~ AND N

11

;.,

IS 6403: 1981

1,’,.8 tj c-m

FIG. 2 CHART FOR STATIC CONE TEST

The value c,f c shall be rrbtainet! from unetrnfil]wl compressivestrength test. Alternatively, it can also be de] ivecl from stalic cone test( JCg5.3.1.2). The values of JC, dc and ie ma:; be obtaint+ as it! 5.1 Ifthe shear strength for a depth of ~i3 beneath the founciatioll does notdepart from the average by more tl-san 50 percent, the average may beused in the calculation.

5.3.1.2 Alternately, cohesion c shall be determined from the staticcone point resistance qe using the empirical relaticmship shown below:

Soil Typ Poini Resiltcmct Vahscs Rarrgt of Undraintd( q. ) kgf/cm$, Cohesion { kg f/cm: )

Normally consol\- q. <20

dated claysq,/’:8 to gC/15

Over consolidated q. > 20clays

5.3.2 Two Lir~ertd Sjstem — In the case of two layered cohesive strilsystem ~’hich do not exhibit marked anisotropy the ultimate net bearingcapacity of a strip footing can be calculated by using the formula givenbe[,~w:

qa - c1 N.

where N= may be obtained from Fig. 3,

IS 6403:1981

5.3.3 Dcsiccatcd Soil — In the case of desiccated cohesive soils, the un-drained cohesion is likely to decrease along with depth and is likely togetstabilized atsomedeptll below grrJl]nd kvel, usually 3“5m, if otherfactors do not influence. If u plot of undrained cohesion, values asshown ir] Fig. 4 is obtained, anti where the pressure bulb falls within thedesiccated top soil the ultimate net bearing capacity shall be obtained

f]om Table 4.

c1

p

c,.

u

‘:~.;~~~/ f+-~____i‘ ~ ~ i 1,

;———.--~--..1 ---~--~-–- ;n~o!p.~

1“ i: ~P.—..- . . ..— <. ... . . ...!. —.l.— .’

,,1’. .. . . .., ~ ,. ... L....—-..i ‘“- ‘—’”-‘~’””––-;-

1’

~/ ~--- ~–+--- +.–.;-.–-.;-----~..-,/ 06— .——. ..-. —,—..—

‘/6 -----i---i--<--l- ---+-l- --::’!i

l---:VET/’-TT--l---TT----!i‘t

‘bflm”ttt--lFIG. 3 BEARING CAPACITY FACTORS FOR LAYERED

COHESIVE SOIL DEPOSITS

13

IS 6403:1981 .

--

A- DECREASE IN COHESION, CIN kgf/cm2 PER UNIT DEPTH OFFOUNDATION SOIL IN cm

FXG. 4 BEARING CAPACITY FACTORS FOR DESICCATED COHESIVE SOIL

TABLE 4 DATA FOR DETERMINING ULTIMATE NETBEARING CAPACITY

qd—c1

0’0 97

0“2 so

0“4 +5

0’6 40

0“8 “ !+6

1’0 3“2

A, c1 shall be obtained from the borehole data, and for a known valueof the width of the strip footing ‘B’, by trial and error qa can be

8ABestimated by matching ————with -f$.

qd

6. ALLOWABLE BEARING CAPACITY

6.1 The allowable bearing capacity shall be taken as either of thefollowing, whichever is less:

a) Net ultimate bearing capacity as obtained in 5 divided by suit-able factor of safety, that is, net safe bearing capacity.

14

.,,-.. .

IS 6403: 1981

b; ~he net soil pressure (~ec6.1.l ) that can beimposedon the basewi[t~out the settlement exceeding the permissible values as giveniri IS : 1904- 1978* to be determined for each structure and typeof soil, that is, safe bearing pressure.

6.1.1 Safe Bearing Prersure — The permissible settlements for differenttypes of soil formations are specified’in IS : 1904- ~978*. The methodsfor calculations of settlements for assumed pressure are specified inIS :8009 ( Part i )- 1976t; by calculating the settlements for two or threeprobable soil pressures and interpolating, the net soil pressure for per-missible settlement may be estimated.

*Code of practice for structural safety of buildings: Shallow foundation ( swofidrevision ).

tCode of practice for calculation of foundations: Part I Shallow foundationssubjcctcd to symmetrical static vertical loads.

15

IS 6403: 1981

( Continuedfrom )dgr 2 )

Ikaririg Capacitv of I?oundaiiorl Subctxnmittec, 13DC 43:4

BUREAU W INDIAN STANDARDS

Headquarters:

Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI 110002Telephones. 3230131, 3233375, 3238402Fax :91113234082, 91113239393, 91113239382

Tetegrams : Manaksanstha(Common to all Ofilces)

Central Laboratory: Te&@rone

Plot No. 20~, Sita Iv Sahibabad lndusVial Area, SAHIBABAD 201010 8-770032

Raglonal Offices:

Cantml : Manak Bhavan, 9 Bahadur Shah Zatar Marg, NEW DELHI 110002 3237617

“Eastern : 1/14 CIT Scheme Vll M, V.I.P. Road, Maniktola, CALCLJTTA700054 3378662

Northern : SCO 335-336, Sector 34-A, CHANDIGARH 160022 603843

Southern : C.I.T. Campus, IV Cross Road, CHENNAI 600113 2352315

tWestern : Manakalaya, E9 Behind Marol Tdephone Exchange, Andheri (East), 8329295MUMBAI 400093

Briwch offlcaa:

‘Pushpak’, Nurmohamed Shaikh Marg, Khanpur, AHMEDABAD 380001

$Paenya Industrial Area, 1st Stage, Bangalore - Tumkur Road,BANGALORE 560058

Gangotri Complex, 5th Floor, Bhadbhada Road, T. T. Nagar, BHOPAL 462003

Plot No, 62-63, Unit W, Ganga Nagar, BHUBANESHWAR 751001

Kaiaikathir Buildings, 670 Avinashi Road, COIMBATORE 641037

Plot No. 43, Sector 16 A, Mathura Road, FARIDABAD 121001

Savitri Complex, 116 G. T. Road, GHAZIABAD 201001

53/5 Ward No 29, R. G. Barua Road, 5UI By-lane, GUWAHATI 781003

5-8-58C, L. N. Gupta Marg, Nampally Station Road, HYDERABAD 500001

E-52, Chitararyan Marg, C-Scheme, JAIPUR 302001

117/41 8 B, Sarvodaya Nagar, KANPUR 208005

Seth Bhawart 2nd Floor, Behind Leela Cinema, Naval Kishore Road,LUCKNOW 226001

Patliputra Industrial Estate, PATNA 800013

T. C. No. 14/1421, University P. O. Palayam,THIRUVANANTHAPURAM 695034

NIT Building, Second Floor, Gokulpat Market, NAQPUR 440010

Institution of En@reers ( India ) Building, 1332 ShivaJi Nagar, PUNE 411005

“Sales Office is at 5“Chowringhea Approach, 1?O. Princap Street,CALCUTTA 700072

tSales Ofhce is at Novelty Chambers, Grant Road, MUMBAI 400007

&ales Otfrce is at “F’ Block, Unity Building, Narashimaraja Square,BANGALORE 560002

5501348

8394955

554021

403627

21 01 41

8-288801

8-71 1996

541137

201083

372925

218876

238923

262305

621 17

5251 71

323635

271085

3096528

2223971

Printedat NW India Pr&WrgPress, Khurp, Inda

*

AMENDMENT NO, 1 MAY 1984

TO

1S:6403-1981 CODE OF PRACTICE FOR DETERMINATIONOF BEARING CAPACITY OF SHALL(W FOUNDATIONS

(First /?0vi8ion)

Alterations---- -.

(Page 10, eb8e S.2,2, I.aetaentince)Substitute the folloving for the exhtlng sentence:

‘In computing the value, any individual value morethan 50 percent of the average calculated shall beneglected end average re-calculated (the values for

all loose seams shall however be included). t

(Page 13, cliwe 5.3.3):

a) Mte 3 - Substitute ‘around* for ‘usually’

b) Lhe 6 - Add the words ‘with the assumption

Of cylindrical failure surfacef after‘obtained’

(Page 13, Fig. 3) - Substitute ‘c2/clt for ‘cl/c2’.

(Page 14, Fig. 4, capt~m) - Substitute thefollowing for the existing caption:

‘Decreasing Cohesion vith Depth in Case of Kh?siccatedCohesive Soil’

(Page 14, Table 4 andctuaa 5.3.3) - Substitute

‘4AB’ for ‘6AEI’

‘d ~

1

,

(Page 25, chuse Cl. 1, line 3) -‘from standard penetration resistance’

(Page 15, cl.uuee 6.1.1) -Add thesentencein the end:

Add the wordsafter ‘pressure’.

follouing

‘TMs safe bearing pressure cm also be calculatedbased on plate load test (See 1S:1888-1982s).”

(Page 25, foot-noteWith ‘*’ nmk) .-Add thewords ‘of settlement’after ‘calculation’.

(Page 15, foot-note) - Add the following additionalfoot-note:

‘sMethodof load test on soils (second ZWV~8~~)t.

(73DC 43)