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DESIGN OF SPREAD FOOTINGS
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PUNCHING SHEAR (Two – way action)
(psi) '4 cc f v
shear For58.0
(MPa) 3
'cc
f v
τ 1
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WIDE BEAM SHEAR
(MPa) 6
'cc
f v
shear For58.0
(psi) '2cc
f v
FBD of efgh:
qU
τ2
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BENDING MOMENT
bendingFor90.0
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BENDING MOMENT
'59.01M 2u
c
y y f
f f bd
bendingFor90.0
Alternative equation
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)thickness(uniform 002.0min
65.0ksi4'05.085.01 c f
)thickness(variable 4.1
min y f
bmax 75.0
(MPa) 600
600'85.0
1 b
y y
c
f f
f
65.0MPa30'008.085.01 c f
(ksi) 000,87
000,87'85.0 1 b
y y
c
f f f
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Minimum length of embedment L d for reinforcing bars in tension :
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Development length for bond for compression bars is the largest of thefollowing:
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