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Design of Pile Cap of Column at C (Intermediate Column

)
Assume, Diameter of pile cap = 500 mm
Assume, Capacity of pile cap = 450 mm
Axial load = 3278.538 KN MX = 54.47 KN-m MY = 40.71 KN-m
3278.538
∴ No. of piles = = 7.29 ≈ 8
450

Y
750 1250 625 625 1250 750

750
5 6 7 8
625
X X
625
1 2 3 4
750

Y
Reaction on The Pile:

P Mxx My y
R= n + ∑x
2 + ∑y
2

P1 = P2 = P3 =
Pile P Mxx My y R = R1 + R2
x y x2 y2
No. n ∑x
2
∑y
2 + R3

- - 409.81
1 3.516 0.391 -6.536 -8.142 395.139
1.875 0.625 7
- - 409.81
2 0.391 0.391 -2.179 -8.142 399.496
0.625 0.625 7
- 409.81
3 0.625 0.391 0.391 2.179 -8.142 403.854
0.625 7
- 409.81
4 1.875 3.516 0.391 6.536 -8.142 408.212
0.625 7
- 409.81
5 0.625 3.516 0.391 -6.536 8.142 411.423
1.875 7
- 409.81
6 0.625 0.391 0.391 -2.179 8.142 415.780
0.625 7
409.81
7 0.625 0.625 0.391 0.391 2.179 8.142 420.138
7
8 1.875 0.625 3.516 0.391 409.81 6.536 8.142 424.496

870 Check for One Way Shear: Maximum shear force = 1621.4.780) X 0.838 KN VU 1621.875 = 2076.780+420. about Y-Y due to pile no. 3.485 Y 1044.689 15409.689 & fck = 25 N/mm2. B. From Table 19.323 X 106 = 0. G-1.2.M. B.54 mm Let us provide 500 mm depth.3.625 = 1004.496+415.8 = (403.618 7239. 2076. B.541 + 50 + 16 + 2 = 452.725 N/mm2 τC τV For pt = 0.1(c)] Or. 5.139+399.625 3.6 = (395.1 & Cl.323 KN-m Check for Required Depth: For M20 & Fe415 material combination. d = 378.138+424.854+408. about X-X due to pile no.875 + (399.138 X 20 X 5250 X d2 Or. 2 = 426 mm AST Calculation: Direction Mu MU/bd2 pt AST Spacing X 2076.838 X 1000 τV Nominal shear stress = bd = 5250 X 426 = 0.212) X 0.323 KN-m b.7.625 = 2021. = 0.554 N/mm2 < .179 0.M.094 0.496+403. 1.8 = (411. 7 2 2 ∑x = ∑y = 15. 16 ∴ dprovided = 500 – 50 – 16 .7.323 2. about Y-Y due to pile no.5.898 2.2.423) X 1.M.4 = (395. Mu max = 0.496) X 1.854+420. = 378.625 + (408.496) X 0.188 KN-m b.139+411.898 KN-m MU max = 2076. 1.423+415.138) X 0. about X-X due to pile no.851 KN-m Bending Moment about Y-Y: a.541 mm 16 ∴ Dreqd.M.138fckbd2 [From Note of Cl.6.125 Bending Moment about X-X: a.625 = 1044. B. 38.212+424.

τC VUS = VU . for ∅ = 10 mm.6 = 8.98 KN/cm From Table 62 of SP 16. bd = 1621.838 X 103 – 0. Capacity of pile cap = 450 mm Axial load = 1778.49 KN-m 1778.817 d = 42.95 ≈ 4 450 Y 750 625 625 750 750 3 4 625 X X 625 1 2 750 Y Reaction on The Pile: P Mxx My y R= n + ∑x 2 + ∑ y2 Pile x y x2 y2 P1 = P2 = P3 = R = R1 + R2 . ∴ Shear design required. Diameter of pile cap = 500 mm Assume.554 X 5250 X 426 = 382.817 KN V US 382.436 ∴ No.436 KN MX = 122. Spacing = 60 mm Let us provide 10 ∅ 1-legged stirrup @ 60 mm c/c Design of Pile Cap of Column at C (Corner Column) Assume. of piles = = 3.

G-1. 16 ∴ dprovided = 400 – 50 – 16 .62 0.391 -48.3 = 2 X 395.322 5511.605) X 0.M.391 0.6 3 0.595 .996 0. about Y-Y due to pile no. P Mxx My y No.6 1 0.030 Y 555.6 4 0.563 1.902 0.000 493.12 mm Let us provide 400 mm depth.62 0.12 mm 16 ∴ Dreqd. 38.006 X 106 = 0.62 0. 1.M.391 0.12 + 50 + 16 + 2 = 359. d = 285.391 48.006 KN-m Check for Required Depth: For M20 & Fe415 material combination.62 444. 2 = 326 mm AST Calculation: Direction Mu MU/bd2 pt AST Spacing X 617.996 0.605 5 09 5 - 0.625 = 494.62 444. B.613+493.996 0.4 = 2 X 493.625 = 617.613 X 0.62 0. Mu max = 0.006 1. 1.391 0.000 493.996 0.2 or 3.391 -48.1(c)] Or.4 = (395.106 0. B. = 285.761 1.605 5 5 09 2 2 ∑x = ∑y = 1. n ∑x 2 ∑y 2 + R3 .62 444.583 5226.613 5 09 5 0.613 09 5 5 - 0. about X-X due to pile no.391 0.516 KN-m b.006 KN-m Bending Moment about Y-Y: B.62 0.605 X 0.M. about X-X due to pile no.138fckbd2 [From Note of Cl.761 KN-m MU max = 617.000 395. - 444. 2.6 2 0.625 = 555. 617.1 & Cl.000 395.138 X 20 X 5250 X d2 Or.563 Bending Moment about X-X: a.391 48.

for ∅ = 10 mm.218 X 1000 τV Nominal shear stress = bd = 2750 X 326 = 0.218 X 103 – 0. From Table 19.Check for One Way Shear: Maximum shear force = 889. bd = 889.6 = 13.983 d = 32.516 X 2750 X 326 = 426. Spacing = 50 mm Let us provide 10 ∅ 1-legged stirrup @ 50 mm c/c . = 0. τC VUS = VU .516 N/mm2 < ∴ Shear design required.983 KN V US 426.992 N/mm2 τC τV For pt = 0.218 KN VU 889.583 & fck = 25 N/mm2.1 KN/cm From Table 62 of SP 16.