RAFT

RAFT with Analytical Loads and Soil Support (Sub-grade Modulus)

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 RAFT

Applied Live load on Raft, KN/m2

Applied Super Imposed load on Raft, KN/m2

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 RAFT

Required Reinforcement (mm2/m)

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 RAFT
PUNCHING CHECK:
Punching Shear Check As Per ACI318-14
1- Input data
1-1 Section properties
Column size Parallel to Y) C1 350 mm
Column size Parallel to X) C2 1200 mm
Effective depth d 1200 mm
1-3 M aterials properties
Concrete strength f c' 45 MPa
Rebar yield stress fy 460 MPa
Shear Rebar yield stress f yt 460 MPa
1-4 Loading
Axial force Pu 10500.00 KN
Moment about Axis y M u1 (M y ) 600.00 KN.m
Moment about Axis x M u2 (M x ) 1100.00 KN.m
2- Applied stresses calculations
2-1 Critical Section properties ACI318M-14 Ref.
Punching shear is check ed on a perimeter 0.5d=600 mm from the column face. Table 8.7.7.1.2
Length parallel to x-x axis. b 1 2400 mm
Length perpendicular to y-y axis. b 2 1550 mm
Critical perimeter b 0 = 2b 1 +2b 2 7900 mm
A p = b 0 .d = 9480000.0 mm²
2-2 M oment M 1 parameters
γ f1 =1/[ 1+(2/3) √(b 1 / b 2 )] = 0.547 eq 8.4.2.3.2
γ v1 =1- γ f1 = 0.453 eq 8.4.4.2.2
8.81E+12 mm 4
2-3 M oment M 2 parameters
Length parallel to Moment Dir. b 2 1550 mm
Length perpendicular to Moment Dir. b 1 2400 mm
γ f2 =1/[ 1+(2/3) √(b 2 / b 1 )] = 0.651 eq 8.4.2.3.2
γ v2 =1- γ f2 = 0.349 eq 8.4.4.2.2
4.65E+12 mm 4
2-4 Stress due to applied loads
v u,A =P u /A p + γ v .M u1. C AB /Jc + γ v .M u2 .C AD /Jc = 1.21 N/mm² Clause 8.4.4.2.3
v u,B =P u /A p + γ v .M u1. C AB /Jc - γ v .M u2 .C BC /Jc = 1.08 N/mm²
v u,C =P u /A p - γ v .M u1. C CD /Jc - γ v .M u2 .C BC /Jc = 1.01 N/mm²
v u,D =P u /A p - γ v .M u1. C CD /Jc + γ v .M u2 .C AD /Jc = 1.13 N/mm²

20

15
v u.M1 = γ v .M u1. C AB
10/Jc 0.04 N/mm²
v u.M1 = γ v .M u1. C AD /Jc 0.06 N/mm²
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-80 -60 -40 -20 0 20 40 60 80
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-10

-15

-20

3- Check of capacity
3-1 Concrete capacity ACI318M-14 Ref.
For rectangular column β = l/b = 3.43 Clouse 22.6.5.2
Cap,vc shall be the smallest of (a), (b), and (c): table 22.6.5.2
(a) : v c3 = 0.33.λ.√f’ c . = 2.21 N/mm² table 22.6.5.2 case (a)
(a) : v c1 = 0.17(1+2/β).λ.√f’ c . = 1.81 N/mm² table 22.6.5.2 case (b)
(c) : v c2 = 0.083(2+40d/b 0 ).λ.√f’ c . = 1.76 N/mm² table 22.6.5.2 case (c)
ϕ for shear = 0.75 table 21.2.1. (b)
ϕ v c = ϕ Min( V c1 ,V c2 ,V C3 ) = 1.32 N/mm² table 22.6.5.2
3-1 Adequacy Check
Maximum Applied shear stress 1.21 N/mm²
Concrete shear capacity ϕ v c = 1.32 N/mm² table 22.6.5.2
capacity check vu < ϕvc OK
Shear Ratio 91%

4- punching shear reinforcement

So, Safe

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