PILECAP DESIGN CALCULATIONS
Project Name	:	Sample
Client Name	:	Sample
Engineer Name	:	Sample
Design File	:	D:\Bentley\Common data\Bentley Communities\ACI\ACI_M_Validation Sheets\STAAD file\RCDC-Staad-Demo -with RCC wall-Pilecap-1.rcdx
Analysis File	:	D:\Bentley\Common data\Bentley Communities\ACI\ACI_M_Validation Sheets\STAAD file\RCDC-Staad-Demo -with RCC wall.std
Analysis Last Modified	:	8/19/2020 6:09:29 PM

Definitions: 1. α = Coefficient of Thermal Expansion 2. ρact = Percentage steel provided 3. A1 = Area of Base for Load Transfer in 'sqm' 4. A2 = Area of Bearing under column in 'sqm' 5. AsfrPrv = Area of face reinforcement provided in 'sqmm' 6. AsfrReq = Area of face reinforcement required in 'sqmm' 7. AstPrv = Area of tensile reinforcement provided in 'sqmm/m' 8. AstReq = Area of tensile reinforcement required in 'sqmm/m' 9. AsvPrv = Area of shear reinforcement provided in 'sqmm/m' 10. AsvReq = Area of shear reinforcement required in 'sqmm/m' 11. Av = Location of section of shear-check from Pile Center 12. Beff = Effective Width for design for bending and shear in 'mm' 13. Beffsfr = Effective Width for design for Face Reinforcement in 'mm' 14. BMux = Factored Design Bending Moment for pile-cap along column D in 'kNm' 15. BMuy = Factored Design Bending Moment for pile-cap along column B in 'kNm' 16. Cx = Width of column in 'mm' 17. Cy = Length of column in 'mm' 18. D = Depth of Pilecap in 'mm' 19. Deff = Effective Depth of Pilecap in 'mm' 20. DfCol = Distance of Pile center to face of column in 'mm' 21. Icr = Moment of Inertia of concrete crack section in 'mm4' 22. Mcr = Cracking Moment 23. Mx = Bending Moment in column along Column D (from analysis) in 'kNm' 24. My = Bending Moment in column along Column B (from analysis) in 'kNm' 25. P = Axial load in pile due to Ptotal in 'kN' 26. Pcomb = Axial load in column for a load combination in 'kN' 27. Ppile = Axial Load on pile in 'kN' 28. Ptotal = Total vertical load on pile-cap for a load combination in 'kN' 29. Pmx = Axial load on pile due to moment Mx in 'kN' 30. Pmy = Axial load on pile due to moment My in 'kN' 31. sp = Spacing Between bars at outer most layer in 'mm' 32. Temp1 = Peak Hydration temperature in Degree 33. Temp2 = Seasonal Temperature Variations in Degree 34. Vc = Nominal shear strength provided by concrete in 'kN' 35. Vs Capacity = Shear strength capacity of provided shear reinforcement 'kN' 36. Vu = Design shear force in 'kN' 37. Vus = Design shear force for stirrups in 'kN' 38. Vs = Nominal shear strength provided by shear reinforcement, in 'kN' 39. Vx = Shear in Column along major axis (from analysis) in 'kN' 40. Vy = Shear in Column along minor axis (from analysis) in 'kN' 41. y = Neutral axis depth in 'mm' 42. φ = Strength reduction factor in shear 43. φ1 = Strength reduction factor in concrete bearing 44. Φ1Pnb = Bearing strength of column in 'kN'   Code References: ACI 318M - 2011 1. Ptmax : 10.3.5 2. Ptmin : 7.12.2.1/10.5.4 3. Pt : 10.3 4. Vc : 11.11.2.1 5. Vcper : 11.2.2 6. AvReq : 11.4.7 7. Min Shear Reinf : 11.4.6 8. Max Stirrup Spacing : 11.4.5 9. One Way Shear Criteria : 15.5 10. Load transfer : 10.14 11. fs,perm : 10.6.4 12. fc,perm : 10.2.7.1 13. Wcr : Eq 4.2(a)   BS 8007 (For Early / Initial Thermal Cracking) 1. Surface Zone for suspended slab : Figure A.1 2. Surface Zone for ground slab : Figure A.2 3. Factors for the calculation of minimum reinforcement : Table A.1   Design Code : ACI 318M - 2011   Pilecap No : PC23   Column No : C23 (600 mm X 800 mm) Member Ref. No : 1901           Concrete Grade : C20   Steel Grade : Fy420   Clear Cover : 50 mm Top of pile-cap below ground : 3.25 m         Density of Soil = 18 kN/cum Founding Depth = 4 m Pile Capacity in Compression = 1250 kN Pile Capacity in Tension = 150 kN Pile Capacity in Shear = 200 kN Pile Capacity Reduction = 0 % Pile Overloading = 10 % Pile Group Overloading = 10 % Pile Capacity Increase for EQ = 0 % Pile Capacity Increase for Wind = 0 % Live Load Reduction = 0 %         Consider Capacity Design : No   Consider Overburden Pressure : Yes           No. of Piles = 3   Pile Diameter = 750 mm Pile Spacing = 2.5 x Ø Pilecap Size = 2481 mm (edge) Pilecap Depth = 750 mm Pilecap Offset = 150 mm Soil Wt. + Pile-cap Wt. = 391.4 kN                   Check for Maximum Load on One Pile: Critical Load Combination : [8] : (LOAD 1: LOAD CASE 1) +0.75 (LOAD 2: LOAD CASE 2) +0.525 (LOAD 4: LOAD CASE 4 EQ-Y) Pcomb = 2964.38 kN Ptotal = Pcomb + (1 x Soil Wt.) + (1 x Pilecap Wt.)   = 3355.79 kN Mx = -136.59 kNm My = -6.44 kNm P = Ptotal/ No. of Piles   = 1118.6 kN Pmx = 84.12 kN Pmy = 0 kN         Maximum load on pile = 1202.71 kN Allowable load on pile = 1250 x 1.1   = 1375 kN   Check for Maximum Load on Pile Group: Critical Load Combination : [2] : (LOAD 1: LOAD CASE 1) +(LOAD 2: LOAD CASE 2) Pcomb = 3148.3 kN Ptotal = Pcomb + (1 x Soil Wt.) + (1 x Pilecap Wt.)   = 3539.71 kN Mx = -17.22 kNm My = -6.14 kNm         Maximum load on pile group = 3539.71 kN Allowable load on pile group = 3 x 1250 x 1.1   = 4125 kN   Check for Maximum shear on Pile Group: Critical Load Combination : [5] : (LOAD 1: LOAD CASE 1) +0.7 (LOAD 4: LOAD CASE 4 EQ-Y) Pcomb = 2442.7 kN Ptotal = Pcomb + (1 x Soil Wt.) + (1 x Pilecap Wt.)   = 2834.1 kN Mx = -172.1 kNm My = -5.17 kNm Vx = 2.61 kN Vy = -65.45 kN Maximum shear on pile group = sqrt(2.612 + -65.452) = 65.5 kN Shear capacity of pile group = 3 x 200 x 1 x 1   = 600 kN   Check for Uplift Load on Pile: No uplift in any pile   Design for Bending: Bottom Reinforcement Along Parallel Edge Critical Load Combination : [15] : 1.2 (LOAD 1: LOAD CASE 1) +1.6 (LOAD 2: LOAD CASE 2) Pcomb = 4054.19 kN Ptotal = Pcomb + (1.2 x Soil Wt.) + (1.2 x Pilecap Wt.)   = 4523.88 kN Mx = -23.23 kNm My = -8.19 kNm Ppile = Max Load on pile   = 1505.17 kN         Deff = 670 mm Beff = 1050 mm DfCol = 0.64 m BMux = Ppile X DfCol   = 959.55 kNm PtReq = 0.58 % AstReq (BM) = 3886.91 sqmm/m AstPrv = #25 @ 130 C/C   = 3897.77 sqmm/m   Top Reinforcement Along Parallel Edge D = 750 mm AstReq = Min Pt for Top Reinforcement X D X 1000   = 0.18% X 750 X 1000   = 1350 sqmm/m AstPrv = #16 @ 145 C/C   = 1369.38 sqmm/m   Bottom Reinforcement Along Perpendicular Edge Critical Load Combination : [19] : 1.2 (LOAD 1: LOAD CASE 1) +(LOAD 2: LOAD CASE 2) +1.4 (LOAD 4: LOAD CASE 4 EQ-Y) Pcomb = 3609.75 kN Ptotal = Pcomb + (1.2 x Soil Wt.) + (1.2 x Pilecap Wt.)   = 4079.44 kN Mx = -341.99 kNm My = -9.12 kNm Ppile = Max Load on pile   = 1570.42 kN         Deff = 690 mm Beff = 1050 mm DfCol = 0.68 m BMuy = Ppile X DfCol   = 1071.86 kNm PtReq = 0.61 % AstReq (BM) = 4234.98 sqmm/m AstPrv = #25 @ 115 C/C   = 4406.17 sqmm/m   Top Reinforcement Along Perpendicular Edge D = 750 mm AstReq = Min Pt for Top Reinforcement X D X 1000 = 0.18% X 750 X 1000   = 1350 sqmm/m AstPrv = #16 @ 145 C/C   = 1369.38 sqmm/m         Design for One Way Shear: Along Parallel Edge Critical Load Combination : [15] : 1.2 (LOAD 1: LOAD CASE 1) +1.6 (LOAD 2: LOAD CASE 2) Pcomb = 4054.19 kN Ptotal = Pcomb + (1.2 x Soil Wt.) + (1.2 x Pilecap Wt.)   = 4523.88 kN Mx = -23.23 kNm My = -8.19 kNm Ppile = Max Load on pile   = 1522.27 kN         Location of critical section is at d/2 from face of column Section Location from column center = 635 mm         Data for Piles       Pile No Load (kN) % covered Shear (kN) P1 1522.27 0 0 P2 1505.17 9.67 1359.67 P3 1496.44 9.67 1351.78   Design Shear Force (Vu) = Max. of (Shear due to P2, P3)   = 1359.67 kN Deff = 670 mm Beff = 2098.95 mm φVc = 853.45 kN Vu > φVc, Hence Provide Shear Reinforcement Vs = 674.96 kN Vs Permisible = 4150.83 kN AsvReq = 1000 X (Vs X 1000) / (fy X Deff)   = 2398.58 sqmm/m AsvPrv = 9928 sqmm/m   = 5L-#16 @ 100 C/C Vs Capacity = 2793.74 kN Vu < φVc+Vs Capacity  Hence Ok   Along Perpendicular Edge Critical Load Combination : [19] : 1.2 (LOAD 1: LOAD CASE 1) +(LOAD 2: LOAD CASE 2) +1.4 (LOAD 4: LOAD CASE 4 EQ-Y) Pcomb = 3609.75 kN Ptotal = Pcomb + (1.2 x Soil Wt.) + (1.2 x Pilecap Wt.)   = 4079.44 kN Mx = -341.99 kNm My = -9.12 kNm Ppile = Max Load on pile   = 1570.42 kN         Location of critical section is at d/2 from face of column Section Location from column center = 745 mm         Data for Piles       Pile No Load (kN) % covered Shear (kN) P1 1570.42 5 1491.97 P2 1259.37 77.16 287.58 P3 1249.64 77.16 285.36   Design Shear Force (Vu) = Max. of (Shear due to P1, P2+P3)   = 1491.97 kN Deff = 690 mm Beff = 1602.18 mm φVc = 676.37 kN Vu > φVc, Hence Provide Shear Reinforcement Vs = 1087.47 kN Vs Permisible = 3263.02 kN AsvReq = 1000 X (Vs X 1000) / (fy X Deff)   = 3752.48 sqmm/m AsvPrv = 15128 sqmm/m   = 8L-#16 @ 105 C/C Vs Capacity = 4384.09 kN Vu < φVc+Vs Capacity  Hence Ok   Design of Face Reinforcement: AsfrReq = SFR % X D X Beffsfr = 0.05 X 750 X 500 / 100 = 187.5 sqmm Asfr Prv = 3-#10 = 213 sqmm   Check for Load Transfer from Column to PileCap Critical Load Combination : [15] : 1.2 (LOAD 1: LOAD CASE 1) +1.6 (LOAD 2: LOAD CASE 2) P = 4054.19 kN A2 = 0.48 sqm A1 = 5.43 sqm Base Area = 5.43 sqm A1 < Base Area   Modification Factor = SquareRoot(A1/A2) < = 2 SquareRoot(A1/A2) = 3.36   Thus, Modification Factor = 2   Φ1Pnb = Φ1 x 0.85 x Modification Factor x A2 x Fck x 1000   = 0.65 x 0.85 x 0.48 x 2 x 20 x 1000   = 10608 kN Φ1Pnb > P, Hence Safe.