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PAD FOOTING DESIGN AND

CONSTRUCTION PART 1

 PREPARED BY AHMAD HAKIMIBIN MAT NOR

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BEARING CAPACITYANALYSIS

BEARINGCAPACIT YFAILURE

Foundationconsiderationrest on densesand @ stifcohesive soil

a! Generalshear "ailure

#! Local shear"ailure

c!Punchin$shear "ailure

Foundationconsiderationrest on sand @cla%e% soil o"&ediu&co&'action

Foundationconsiderationrest on "airl%loose soil

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Plastic Analysis Of Ba!in" Ca#acity $T!%a"&i

III III

I

IIII

+

Zone I : Triangular Zone

Zone II : Zone of Radial Shear 

Zone III : Rainkine Passive Zone

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Allowable bearing capacity (qa)

The allowable bearing capacity , qa is the loading per unit area thatthe soil is able to support without unsafe oveent,

(here)*a + allowable bearing capacity

qult ! ultiate bearing capacity

"S ! safety factor

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Ulti'at ,a!in" ca#acity in c(&si- s(il$./lt*

 The #asic 'rinci'le in evaluatin$ the #earin$ ca'acit% o" cohesivesoil cla%e%! soil is #ast instroduced #% Ter,a$hi Ter,a$hi andPec-./012!3 

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Note ) e is the #ase o"natural lo$arith&s4a''ro5i&atel% 632/767

 The line on 8$ure 039re'resentin$ N: ;as"ound #% 'lottin$ valuesdeter&ined in studies

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Local Shear Failure

C> and ?>

qu ! c#$#c % &'(f  $#q % )*+& -$#&

Shear Stren$th 444 C and ?

Note)4 Loose sand and so"t cla% + Local shear"ailure-

ense Sand and ard Cla% + General shear"ailure@4? 1 D + General shear "ailure4? 60 D + Local shear "ailure

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Raah039

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EFFECT OF 3ATER TABLE ONBEARING CAPACITY 

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Cas III3 (hen the ;ater ta#le is located so that d B. the;ater ;ill have no efect on the ulti&ate #earin$ ca'acit%

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