Design Abutment Foundation
Page 1
2.0 Design of Substructure 2.1 Design of Abutment Section of Abutment 0.25
0.4
40 m Standard DoR Superstructure 10 Nos of Span 215.5 Deck Level Concrete Grade 3 All Concrete M30
1.5
0.3 A6 A7
1.0
0.5 0.61
A5
0.5
3.4
A2
0.9
3.5
210.5 HFL
0.00 A3
3.50 6.50 Y
1.0020
A1
206.7 AGL 203.00 LBL
0.01 4.005 A4
x
0.4
A
204.60 SBL 1.50
1.50
0.30
A8
203.1 CTL This prelimanry section is defined by considering hydrological analysis and geotechnical recommendation
T
SBL = Stem Bottom Level CTL = Cap Top Level AGL = Average Ground Level
Material Properties Concrete grade Steel grade Allowable stress of steel in tension and shear Allowable stress of steel in direct compression Allowable compressive stress in concrete in flexure Allowable comp. stress in concrete in direct compression Modular ratio (m) Neutral axis factor The resisting moment coefficient
(fck) (fe) Sst = Ssc = Scbc = Scc = m=
30 500 240 205 10.00 7.5
N/mm² N/mm² N/mm² N/mm² N/mm² N/mm²
10
k
0.29
j
0.90
R
1.33
IRC:21-2000, 303.2.1, Table 9,10 Levels High Flood Level Average Ground Level Total depth of longitudinal Girder including Slab Provided Clear free board Level of Deck Surface Thickness of abutment cap Top level of Footing/cap (SBL) Thickness of Footing/Cap Bottem level of Footing/Cap (FBL) Thickness of Bearing Thickness of Bearing concrete Pad Hence the total height of abutment H=
Abutment_openFoundation
210.5 206.7 3.00 1.5 215.50 0.9 204.60 1.50 203.10 0.3 0.2 10.90
m m m m m m m m m m m m
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 2
As per IRC : 6-2000, 217.1 for Equivqlent live load Surcharge Equivalent Height of Abutment Length of Abutment Span Length
1.2 12.1 11 40
H eq= L=
m m m m
Approach Slab Diamensions Thickness of approach slab Length of Approach Slab Width of Approach Slab Ballast Wall Width of Ballast wall Length of Ballast wall Wing Wall Thickness of wing wall
0.3 m 33.50 50 m 11 m 0.4 m 11 m 0.4 m
Soil Data & Seismic Data Unit weight of backfill soil Unit weight of concrete Horizontal seismic coefficient Vertical seismic coefficient 0.36 Zone Factor (z) Importance Factor(I) 1
conc
A l b t th th Angle between the wallll andd earth Angle of internal friction of soil Angle of friction between soil and wall
16 kN/m³ 24 kN/m³ 0.150 0.075
Degree 0 35 16
Analysis and Design of Abutment Stem Area and C.G Calculation with respect to bottom of stem point A 2
Area (m ) CG-X CG-Y Weight (KN) Symbol A1 1.76 0.20 5.45 464.64 A2 1.35 1.15 6.95 356.40 A3 9.750 1.13 3.25 2574.00 A4 0.98 2.00 2.17 257.40 A5 5.95 -1.17 8.77 57.12 A6 3.50 -1.75 10.40 33.60 A7 0.13 -0.13 10.35 33.00 Total 23.41 3776.16 C G ffrom A C.G 1 0020 1.0020 4 005 4.005 Position of C.G From Superstructure Load Point 0.0080
Forces on the Abutment Total Dead Load from superstructure Total Critical Live load Excluding impact Total Critical Live load including impact
4280.00 KN 1186.00 KN
Earth Pressure force (Including live load surcharge) Total Static earth p pressure = 0.5* * Heq² * tan²(45° ( - / /2)*L ) = Which act at a distance from abutment base (0.42*Heq)
Effect of buyoncy
I.F
1.0978
1282.6 KN
[IRC:6-2000, 217.1] 3491.4575 KN 5.082 m
[IRC:6-2000, 216.4 (a)]
Area of stem at top = Depth of submerged part of abutment = Area of stem at base = Area of stem at HFL = Volume of submerged part of abutment = Taking 1/2 of the volume, Net upward force due to buyoncy =
Abutment_openFoundation
16.5 5.90 19.8 19.495385 115.92138 -579.6069
m² m m² m² m³ kN
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 3
Frictional force due to resistance of bearings For Pot Bearing Vertical dead Load Total No of Bearing Per Abutment
2140 kN 2 2 250000 mm 8.56 kN/mm2
Contact area of Pot Bearing (Assuming size 500mmX500mm) Contact Stress (sp) Pot bearing constant (k) Maximum i Friction i i C Coefficient ffi i μmax =
1.00 0.065
Maxmimum Frictional Force Total Lateral force due to frictional resistance of bearings, Lateral force due to frictional resistance of bearings,
138.36 kN 276.72 kN 276.72 kN
Breaking Force:( As Per IRC:6-2000, 214.2) Braking force = 20% of the weight of the design vehicle (Class A) And this force acts along the bridge at 1.2m above the road level Total weight of the IRC Class A vehicle = Therefore braking force length =
12.10 m from base 543.29 543 29 kN 54.329 kN
Seismic Forces on Abutment [IRC : Seismic Forces Due to back fill and Approach Slab are also considered.
Horizontal seismic forces: Superstructure: Abutment: Backfill soil mass: This forces will act at 0.5 Heq
642.00 566.42 523.72 6.05
kN kN kN m
Vertical seismic forces: Superstructure: Abutment:
321.00 kN 283.21 kN
Loads and Moment Calculation The transverce forces and moments are not calculated since it will not be critical due to high moment of inertia. Taking Moments on C.G of Abutment Load Horizon Vertical H i V i l Coefficient Vertical force Horizontal Lever arm, Particular tal force Lever arm, (kN) (m) IRC:6-2000, (kN) (m) 202.3 combination I Superstructure dead load
Dry case, Non-seismic 1
Increment factor for allowable stresses*
4280.00
Moment (kN.m) 1
0.01
34.17 10.24
Live load
1
1282.55
0.01
Abutment
1
3776.16
0.00
Soil mass
1
0.00 3491.46
5.08
17743.59
Tractive/Braking force
1
54.33
12.10
657.38
Frictional force
1
276.72
7.40
2047.76
3822.51
24.58
20493.14
Total combination VI
9338.71 Dry case, Seismic
Increment factor for allowable stresses*
Abutment_openFoundation
1.5
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation Non seismic forces Superstructure dead load Live load Abutment Soil mass
Page 4 1
4280.00
1.01
0.5
641.28
0.01
4322.80 5.12
1
3776.16
0.00
0.00
1
3491.46
5.08
Tractive/Braking force
0.5
27.16
12.10
17743.59 328.69
Frictional force
0.5
138.36
7.40
1023.88 5074.36
Additi l seismic Additional i mi forces f r Superstructure
1
321.00
0.008
642.00
7.90
Abutment
1
283.21
0.000
566.42
4.01
2268.63
Soil mass Total
1
523.72 5389.13
6.05
3168.50 33935.57
9301.65
combination I-a Flooded case, Non-seismic
Increment factor for allowable stresses*
1
Superstructure dead load
1
4280.00
0.01
34.17
Live load
1
1282.55
0.01
10.24
Abutment
1
3776.16
0.00
Soil mass
1
0.00 3491.46
5.08
17743.59
Tractive/Braking force
1
54.33
12.10
657.38
Frictional force
1
276.72
7.40
2047.76
Buyoncy
1
3822.51
24.58
20493.14
Total combination VI-a Non seismic forces Superstructure dead load Live load Abutment Soil mass
-579.61 8759.10
Flooded case, Seismic
Increment factor for allowable stresses*
1.5
1
4280.00
0.01
0.5
641.28
0.01
34.17 5.12
1
3776.16
0.00
0.00
1
3491.46
5.08
Tractive/Braking force
0.5
27.16
12.10
328.69
Frictional force
0.5
138.36
7.40
1023.88
Buyoncy
1
17743.59
-579.61
Additional seismic forces Superstructure
1
321.00
0.01
642.00
7.90
5074.36
Abutment
1
283.21
0.00
566.42
4.01
2268.63
Soil mass
1
523.72
6.05
Total
8722.04
Maximum Loads
9338.71
Increment factor for allowable stresses*
3168.50
5389.13
29646.94
5389.13
33935.57
IRC:6-2000, 202.3
Abutment_openFoundation
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 5
2.1.1 Design of abutment stem Section Abutment Stem will be designed as compression member with uniaxial moment. Overall Thickness of Stem at base Length of the abutment Gross cross sectional area of the stem percentage of longitudinal tensile reinforcement the percentage of longitudinal compressive reifnrocement Percentage of steel to be provided as per IRC:21-2000, IRC:21 2000 306.2.2 306 2 2 Total percentage of longitudinal reinforcement = Then the initial total area of reinforcement Net area of concrete Let the effective cover (referring to the CG of bars) Hence the effective depth
D= L= Ag =
1800 mm 11000 mm 19800000
pst psc
Asc = Ac = cover (d')= d_eff =
0.25 0.13 03 0.3 0.38 75240 19724760 65 1735
mm² % % % % OK mm² mm² mm mm 4
Moment of inertia I = 4.788.E+12 mm Section modulus Z = 5.519.E+09 mm³ Radius of gyration SQRT(I/Z*L) k= 501 mm Height of the abutment (upto abutment cap) 6500 mm Effective length (height) factor (IRC:21-2000, 306.1.2, Table 13) = 1.75 Effective height of the abutment 11375 mm Ratio of Effective length : Radius of gyration = 22.71 Hence it is treated as a Short Column Th di t The directt comp. stress, Scc_cal = P/(Ac+1.5*m*Asc) N/mm² The comp. stress in bending Scbc_cal = M/Z N/mm² Interaction Condition to be satisfied: [Scc_cal/Scc] + [Scbc_cal/Scbc] = <1 Comp. Stress Non-Seismic Case Seismic Case [Scc_cal/Scc] + [Scbc_cal/Scbc] Condition Scc_cal = 0.45 0.45 0.431 Non sesmic <1 Satisfied Scbc_cal = 3.71 6.15 0.674 Sesmic <1 Satisfied Reinforcement Calculation Reinforcement Tensile reinforcement (AS1+AS2) Compressive Reinforcement
Area (mm2)
Bar dia (mm)
49500
25740 Total area of tensile reinforcement Ast= Total area of compressive reinforcement Asc= (AS3+AS4)
Nos 25 105 20
85
Total provided area of longitudinal steel =
Spacing (mm) c/c 100 AS1 130 51542 26704 80700 0.408
AS2 mm² mm² mm² % OK
Provided Nos 110 85
Check For Shear Critical shear force at the base 3822510.67 N Effective area of the section 19800000 mm² Shear Stress 0.193 N/mm² Permissible Shear Stress 0 270 N/mm² 0.270 [IRC:21-2000, Table 12B]
Abutment_openFoundation
OK
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 6
Check For Cracked or Uncracked Section For uncracked section (Scbc_cal - Scc_cal) < 0.25*(Scc_cal + Scbc_cal) Case (Scbc_cal - Scc_cal) 0.25*(Scc_cal + Scbc_cal) Section is Non seismic condition: 3.27 1.04 Cracked Seismic condition: 5.70 1.65 Cracked As The Section is cracked Reinforcement and section should be checked for cracked condition Critical Neutral axis x 555.16 mm The resultant Stress Scb 4 081 N/mm² 4.081 Stress in tension reinforcement: Ss = m*Scb*(D-d'-x)/x = 86.74 N/mm² < 240 OK Stress in compression reinforcement: Ssc = 1.5m*Scb*(x-d')/x = 54.05 N/mm² < 205 OK
Abutment_openFoundation
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 7
Distribution Bar calculation Let the percentage of distribution bars be
20 % of the total longitudinal reinforcement
Hence, area of distribution bars = Let's use bars of 16 mm Unit area = Total number of distribution bars on each face of the stem = Spacing @ Provided spacing 160 mm and bar dia is No of Bar 56 on each face of stem Development / Lap length to be provided where necessary =
16139.932 201.06 mm² 41 160 16 mm
mm² nos mm c/c (AS3)
1150 mm
Summary of reinforcement of abutment stem Section
AS3 AS1
AS3
Ø 16 @ 160 c/c
AS1
AS3
Ø 25 @ 100 c/c
Ø 16 @ 160 c/c
AS3
Ø 25 @ 100 c/c
Ø 20 @ 130 c/c
Ø 20 @ 130 c/c
Above curtailment
Below curtailment
AS3 AS1
Ø 20 @ 130 c/c
Height of curtailmnet No Curtailment
Ø 25 @ 100 c/c AS3 Ø 16 @ 160 c/c
AS3 AS1
Ø 20 @ 130 c/c
Ø 25 @ 100 c/c
2.1.2 Design of Abutment Cap Calculation of Vertical Load Superstructure Dead Load 4280 Live Load Including Impact 1282.6 Total Load 5562.6 Total Load per Girder 2781.3 No of Longitidunal Girder 2 Depth of Abutment Cap D= 900 Check For Punching Stress: Bearing Size provided L= 500 B= 500 au p = ks(0 au_p ks(0.16 16*sqrt(fck)) sqrt(fck)) Allowable punching Stress = Where ks is minimum of 1 and 0.5 + bc
and bc = B/L
So, ks = Allowable punching Stress tau_p = Total Punching Stress Developed au_developed = V/Po*D
where Po is perimeter of affected Area = 2 (2D+L+B) Po So, Punching Stress Developed au_developed =
KN KN KN KN mm mm mm
1 1 0.876 N/mm²
5600 mm 0.5518 N/mm²
< 0.876 N/mm² Ok As depth is safe for punching no additional reinforcement is required. Providing nominal reinforcement. Reinforcement Bar dia (mm) Reinforcement along length of cap 12 Stirrups around the cap 10 And Provide 2 layers of 8 mm bar mesh of length L: Breadth : Abutment_openFoundation
Nos 28 62 650 mm 650 mm
Spacing (mm) c/c provided
175 175
Level AC1 AC2
AC3
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 8
Summary of reinforcement of abutment Cap Section Ø8mm 2 layers of bar mesh AC3 Ø 10 @ 175 mmc/c AC2
Ø 12 @ 175 mmc/c AC1 Ø 10 @ 175 mmc/c AC2 Ø8mm 2 layers of bar mesh AC3
Ø 12 @ 175 mmc/c AC1
2.1.3 Design of Back Wall/DirtWall Total Horizontal force due to earth pressure including live load surcharge is given by 0.5.s.(height of ballast wall+1.2(eq live load surcharge))2.tan2(45°-/2)*L= which acts at a distance 0.42H from backwall base of Total Seismic earth pressure Including live load surcharge is given by (0.5* g Ka_dyn*H² *L) = Horizontal component of this force = This force acts at 0.5*H, hence lever arm = Self weight of backwall these act at a distance from backwall toe of Moment due to earth pressure about abutment base Moment due to seismic forces Moment due self weight Total Moment about backwall toe Total Base Shear Providing 40 mm cover and total thickness of ballast wall is & dia of main bar & Distribution bar are 25 mm & So, available effective depth = Critical neutral axis, xc = Lever arm , Z =
Scbc*deff/((Sst/m)+Scbc) deff-xc/3
Required area of tensile steel (M/Z*Sst) =
420.16 KN 1.764 m
63.02 kN 2.1 m 316 8 kN 316.8 0.2 m 741.17 kN.m 132.35 kN.m 63.36 kN.m 936.88 kNm 483.19 kN 400 mm 12 mm respectively 322.5 mm 94.85 mm 290.88 mm
13420.09 mm²
So, No of main bar 28 @ spaicng 405 mm c/c Provided Reinforcement Nos Reinforcement Dia of Bar Spacing (mm) c/c provided 210 53 Main Bar (Back Face) 25 Distribution Bar (Horizontal bar at 12 300 11 each face) Compression Bar (Front Face) 20 260 43
Abutment_openFoundation
>300
mm
Level AB1 AB3 AB2
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 9
Summary of reinforcement of Back Wall 250
400 100
Ø 20 AB7
Ø 25 @ 210 mmc/c AB1 Ø 12 @ 300 mmc/c AB3 250 Ø 10 AB5
Ø 20 @ 260 mmc/c AB2 Ø 10 AB6
250
Ø 16 AB8
Ø 16 AB4
2.1.3 Design of Pile Foundation 0.25
0.4
1.5
03 0.3 A6 A7
1.0
0.5
3
0.61 A5
0.5
3.4
A2
0.9
0
3.5
210.5 HFL
A3
10.90
3.50
12.40
6.50 Y
206.7 AGL 203 LBL
A1 0.12
A4
x
3.43
A
204.6 SBL 1.50
1 50 1.50
0.3
A8
203.1 CBL 2.80
1.80 7.40
2.80
195.962 MSL 20.00
183.10 FL ** FL = Foundation Level
Abutment_openFoundation
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 10 210.5
HFL 14.538
206.7
AGL 3.60
203.10
2.10 7.14
195 962 195.962
MSL 6.122603013
20.00
12.86 189.839397
level of fixity
6.74 183.10
Foundation level
0.7 3.00 13.40
7.40 3.00
Length of Pile cap Along Brodge Axis = Length of Pile Cap Across Bridge Axis = Depth of Fixity from maximum Scour Level = (IS 2911 part I section II, Appendix C, Adopting Max value) Diameter Di t off Pile Pil = Depth of Pile = No of Pile in one row = (Along Bridge Axis) No of Row = Total No of Pile (n) = Embedded length of Pile = Thickness of Pile Cap = IRC 78:2000 Cl 709.5
Factor of Saftey FS = IRC 78:2000 Cl 709.3 offset of pile cap from the outer face of outermost pile =
Abutment_openFoundation
7.40 m 13.40 m 6.12 m 1m 20.00 m 3 5 15 12.86 1.50 m OK 2.5 0.2 m Ok
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 11
Center to center distance of the piles Along Bridge Axis (Xi) = Across Bridge Axis (Yi) = Width of Pile Group (Outer Surface of The piles) along Axis (B) = Width of Pile Group (Outer Surface of The piles) across Axis (L) = Area Enclosed by pile Groups (Ag) =
3.00 3.00 6.70 12.70
m m m m 2 85.09 m
Area and C.G Calculation with respect to CG of Pile Cap Area (m2) CG-X Symbol CG-Y Weight (KN) A1 1.76 0.70 6.95 464.64 A2 1.35 -0.25 8.45 356.40 A3 9.75 -0.05 4.75 2574.00 A4 0.98 -0.70 3.67 257.40 A5 5.95 -1.63 10.27 57.12 A6 3.50 2.65 11.90 33.60 A7 0.13 1.03 11.85 33.00 A8 11.10 0.00 0.75 2930.40 Total 34.51 6706.56 C.G from CL of cap -0.0064 3.427 m Position of superstructure load point CG of pile cap= Position of C.G From Superstructure Load Point Height of Abutment (H) Height of Abutment Including Cap (H') Length of Abutment (L) Over all Length of Cap (L') Horizontal Nonseismic Forces Forces due to breaking force Horizontal forces due to reisitence of bearing Earth pressure (0.5* g * H² * tan²(45° - f/2)*L) at 0.42H Vertical Nonseismic Forces Live Load Dead Load from superstructure Dead load of Abutment and Footing Vertical Load of Soil Mass Vertical Load of Approach Slab Horizontal seismic forces:
-0.01 0.12 10.90 12.40 11.00 7.40
m
m m m m m
kN 54.329 276.72 3491.46
kN 1282.55 4280.00 6706.56 2685.76 277.2
kN
Approach Slab
642.00 1005.98 402.86 41.58
Vertical seismic forces:
kN
Superstructure
321.00 502.99 201.43 20.79
Superstructure Abutment and footing Soil mass
Abutment and footing Soil mass Approach Slab
Buyoncy (IRC:6-2000, (IRC:6 2000, 216.4 (a) Upward pressure due to buyoncy =
Abutment_openFoundation
-1981 kN at
Vertical lever arm m 4.20 8.90 5.71 Horizontal lever arm m 0.12 0.12 0.12 2.29 1.94 Vertical lever arm m 9.40 3.43 6.20 12.25 Horizontal lever arm m 0.12 0.12 2.29 1.94 -0.01 m
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 12
115.92 82.14
Volume of Submerged part of Stem Volume of cap
Loads and Moment Calculation Particular
combination I Superstructure dead load
Load Moment Moment Horizon Vertical Coefficient Vertical force Horizontal Lever arm, Along Axix tal force Lever arm, Along Axis (kN.m) (kN) (m) IRC:6-2000, (m) (kN.m) (+ve) (kN) (-ve) 202.3 Dry case, Non-seismic 1
Increment factor for allowable stresses*
4280.00
1
0.12
498.35
Live load
1
1282.55
0.12
149.34
Abutment
1
6706.56
0.12
780.88
Soil mass/earth pressure
1
2685.76
2.29 3491.46
Approach Slab
1
277.2
Tractive/Braking force
1
276.72
8.90
Frictional force
1
54.33
4.20
3822.51
18.81
Total combination VI Non seismic forces
1.94
15232.07 Dry case, Seismic
5.71
13783.24 538.76
Increment factor for allowable stresses*
2462.84 228.18 15750.56
2691.03
1.5
Superstructure dead load
1
4280.00
0.12
Live load
1
1282.55
0.12
498.35 149.34
Abutment
1
6706.56
0.12
780.88
Soil mass/earth pressure
1
2685.76
2.29 3491.46
Approach Slab
1
277.20
5.71
13783.24
1.94
Tractive/Braking force
1
276.72
8.90
2462.84
Frictional force
1
54.33
4.20
228.18
Additional seismic forces Superstructure
1
321.00
0.116
642.00
9.40
37.38
6034.80
Abutment
1
502.99
0.116 1005.98
3.43
58.57
3447.94
Soil mass
1
201.43
2.294
402.86
6.20
462.00
2497.76
Approach Slab
1
20.79
1.944
41.58
12.25
40.41
509.36
15810.15
15180.88
Total
16257.50
combination I-a Flooded case, Non-seismic Superstructure dead load
1
5914.94 Increment factor for allowable stresses*
4280.00
1
0.12
498.35
Live load
1
1282.55
0.12
149.34
Abutment
1
6706.56
0.12
780.88
Soil mass
1
2685.76
Approach Slab
1
277.2
Tractive/Braking force
1
276.72
8.90
2462.84
Frictional force
1
54.33
4.20
228.18
Buyoncy
1
Total combination VI-a Non seismic forces
2.29 3491.46
-1980.61
13783.24 538.76
-0.01
13251.46 Flooded case, Seismic
5.71
1.94
-12.7 3822.51
15737.82
Increment factor for allowable stresses*
Superstructure dead load
1
4280.00
0.12
Live load
1
1282.55
0.12
149.34
Abutment
1
6706.56
0.12
780.88
Soil mass
1
2685.76
Approach Slab
1
277.20
Tractive/Braking force
1
276.72
8.90
Frictional force
1
54.33
4.20
Buyoncy
1
-1980.61
Abutment_openFoundation
498.35
2.29 3491.46
5.71
1.94
-0.01
2691.03
1.5
13783.24 538.76 2462.84 228.18 -12.7
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 13
Additional seismic forces Superstructure
1
321.00
0.12
642.00
9.40
37.38
6034.80
Abutment
1
502.99
0.12 1005.98
3.43
58.57
3447.94
Soil mass
1
201.43
2.29
402.86
6.20
462.00
2497.76
Approach Slab
1
20.79
1.94
41.58
12.25
40.41
509.36
16336.16
15180.88
Total
14297.67
Increment factor for allowable stresses* Summary of Loads Particular/Load cases Vertical force (kN)
5914.94 IRC:6-2000, 202.3
Horizontal force (kN)
Moment Along Axis (kN.m)
Non Seismic case Dry (comb. I) 15232.07 3822.51 Flooded (comb. I-a) 13251.46 3822.51 Seismic case Dry (comb. VI) 16257.50 5914.94 Flooded (comb VI-a) 14297.67 5914.94 Max Loads: 16257.50 5914.94 Maximum load on individual piles Maximum and Minimum Load is given by
Moment Across Axix (kN.m)
15750.56 15737.82
2691.03 2691.03
15810.15 16336.16 16336.16
15180.88 15180.88 15180.88
V max = [V/n] + (Mxx*Xmax)/ Xi² + (Myy*Ymax)/ Yi² V min = [V/n] - (Mxx*Xmax)/ Xi² - (Myy*Ymax)/ Yi²
Moment of Inertia of Piles Xi²=
90.00 m²
Yi²=
1134.00 m²
Maximum Load will be on outermost pile So, X max = Y max = Particular/Load cases Vertical force (kN) f
3.00 6.00
Vmax
Vmin
Non Seismic case Dry (comb. I) 15232.07 1554.73 Flooded (comb. I-a) 13251.46 1422.26 Seismic case Dry (comb. VI) 16257.50 1691.16 Flooded (comb VI-a) 14297.67 1578.04 g of Pile Design Concrete grade Steel grade Allowable stress of steel in tension and shear Allowable stress of steel in direct compression Allowable compressive stress in concrete in flexure Allowable comp. stress in concrete in direct compression Modular ratio (m) Neutral axis factor The resisting moment coefficient
Cover Horizontal Force Per Pile
Recommended Pile Capacity
Hmax from soil Investigation
476.21 254.83 344.60 254.83
1650 1650
OK OK
476.51 394.33 336.35 394.33
2475 2475
OK OK
(fck) (fe) Sst = Ssc = Scbc = Scc = m=
30 500 240 205 10.00 7.5 0.29
j
0.90
R
Abutment_openFoundation
N/mm² N/mm² N/mm² N/mm² N/mm² N/mm²
10
k
Non Seismic Seismic
Remark
1.33
80 mm 254.8 kN 394.3 kN
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 14
Abutment_openFoundation
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 15
2.74E+04 MN/m2
Elasticity of Concrete,
4 4.91E-02 m
Moment of Inertia, Soil Type
Cohensionless Soil
Calculation for Cohesionless Soil
Calculation for Cohesive Soil
Calculate
Not Applicable
ηh
5 MN/m3
3 20000 kN/m
k1 ((IS :2911/Part1/Sec2-2010/Table 4))
(T bl 3 IS 2911) (Table
K orr ηh h
Stiffness Factor T
3.06 m 12.86 m
Embedded length of Pile (Le)
L1
4000
Relative Stiffness Factor, R
0.8 m
Embedded length of pile, Le
7.14 m
L1
12.86 m
7.14 m
L1/T
2.3
L1/R
8.88
Lf/T
2
Lf/R
1.950
Lf
6.12
Lf
Non Seismic Case
Seismic Case
1689.63
Fixed End Moment, MF Reduction Factor, m
1.6 m
2614.52 KNm
0.85
0.85 (IS :2911/Part1/Sec2-2010/Fig. 3, Fixed Head /Amend
Actual maximum moment, M
1436.18
2222.34 KNm
Maximum Axial Force (kN)
1554.73
1691.16
Design For Non Seismic Case
Sectional area of pile = (Ag) Let Provide main reinforcement 1.5 % of Sectional area Total Area of reinforcement Let Provide 25 mm dia bars. Provided Number of Bar 24 Provide in one row Spacing between the bars = 130 Cover provided Let provided diameter of transverse reinforcement the diameter up to the line of reinforcement Dc So Area of Steel Provided (As) So Area of Concrete (Ac) Check for Section capacity of Stem Equivalent area of Section Ae = Ac+(1.5m-1)*As= Equivalent moment of inertia of section Ie = (PI*D^4/64) + (m-1)*As*Dc² / 8
785398.2 mm² 11780.972 mm² (AP5) mm 75 10 850 11780.972 785398.2
mm mm mm mm² mm²
950331.8 mm² 4
6.23E+10 mm
3 124681958 mm 1.636 N/mm² 11.519 N/mm² 1.3700 !!! !!! 1.3460 !!!
Ze = 2*Ie/D = Scc = P/Ae = Scb = M/Ze = (Scc/Sacc + Scb/Sacb) =
Seismic Case:
(Scc/Sacc + Scb/Sacb) =
Summary of reinforcement of Pile Section
Provide 24 nos of 25 mm dia bars Lateral Ties Minimum volume of lateral reinforcement per meter length of pile Volume of tie of 10 mm tie Number of Ties per meter of pile = & Spacing =
APL1 0.3 %
3 2356194.49 mm 3 207261.7 mm 12
84.00
Abutment_openFoundation
mm c/c APL2
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 16
Summary of reinforcement of Pile Section
Ø 25 @ 24 Nos APL1
Ø 10 @ 84 mmc/c APL2 Design of Pile Cap
(Assumed Maximum Loaded Pile at outermost edge)
3.00 2.1 3.00
Bending Moment at the face stem = (per meter width of pile cap) Neutral Axis Factor Xc [m*Scbc/m*Scbc+Sst] = Lever Arm Z [1-Xc/3] = Moment of Resistance Factor R [Scbc/2*Z*Xc] = Minimum Effective depth requireq deff_min [sqrt(M/R*b] =
1325.2 kN-m 0.29 0.90 1.33 999.53 mm
Provided Over all Depth Cover provided (Top and Cover) S effective So, ff ti actual t l depth d pth deff
1500 mm 75 mm 1425 mm Ok 2 4295.9 mm
Area of Reinforcement required Ast [M/Z*deff*Sst] = Provided Reinforcement Reinforcement Tensile Reinforcement (Bottom) Bothway Top Bar (distribution bar) Top Reinforcement Bothway
Dia of Bar 25
Spacing (mm) c/c provided
Nos Per meter Total
120
9
Level
112.00 APC1+2 62.00
Ast Provided (Bottom) 4417 9 mm 4417.9 mm² > Ast required OK Min 0.12 % of gross area 25 mm Ast Provided (Top)
Abutment_openFoundation
120 mm c/c 4090.6 mm² 0.29 %
APC3+4 112 OK
62
Rapti Bridge Design 5_3_Pile.xls
Design Abutment Foundation
Page 17
Check For Shear Shear Force =
Seismic Case
441.41
Non Seismic Case
kN N/mm2
Shear Stress Developed = 0.3098 Reinforcement % = 0.31 N/mm2 Permissible shear Stress = 0.3588 Check For Punching Stress Depth of Section = All Allowable bl punching hi pressure, tau_p = kks(0.16*sqrt(fck)) (0 16* (f k)) Where, ks = the minimum of 1 and 0.5+bc = bc = B/L = 1
285.26
OK
N/mm2
OK
1500.00 mm
So, allowable punching Stress Provide Nominal Chair bar
kN N/mm2
0.2002 0.31 0.2392
Punching stress developed = 10 dia @
1.0 2 0.876 N/mm 2 0.17 N/mm 700 mm spacing
tau_p =
OK APC6
Summary of reinforcement of Pile Cap and Pile Section
Ø 10 @ 700c/c APC6
Ø 25 @ 120c/c APC3&APC4
3 Nos 10 mm bar Periphery APC5
Ø 25 @ 120c/c ( ) (APC1&APC2)
Ø 25 @ 24 Nos APL1
Ø 10 @ 84 mmc/c APL2
Abutment_openFoundation
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
1
2.0 Design of Substructure 2.1 Design of Pier
Section of Pier A
B
0.75 1.48 TPL
1
2.500
2.500
212
2.00 4.45 BPL
210.00
HFL
210.5
LBL
203
SBL
201.50
7.50 2.45
10.50 2.60
12.10
1.60
1.60
FBL 13.40
7.40
This prelimanry section is defined by considering hydrological analysis and geotechnical recommendation Material Properties Concrete grade Steel grade Allowable stress of steel in tension and shear Allowable stress of steel in direct compression Allowable compressive stress in concrete in flexure Allowable comp. stress in concrete in direct compression Modular ratio (m) Neutral axis factor k j The resisting moment coefficient R IRC:21-2000, 303.2.1, Table 9,10 Levels High Flood Level Lowest Bed Level of pier Level of Deck Surface Thickness of Pier cap (overall Thickness) Total depth of longitudinal Girder including Slab Top level of pier cap (TPL) Pier_CAP+STEM
199.9
SBL = Stem Bottom Level FBL = Footing Bottom Level
(fck) (fe) Sst = Ssc = Scbc = Scc = m=
30 500 240 205 10.00 7.5 10 0.32 0.89 0.95
210.5 203.00 215.5 2.00 3.00 212.00
N/mm² N/mm² N/mm² N/mm² N/mm² N/mm²
m m m m m
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
Top level of Footing (SBL) Thickness of Footing/Cap Bottem level of Footing/Cap (FBL) Thickness of Bearing Including Pad Hence the total height of Pier Soil Data & Seismic Data Unit weight of backfill soil Unit weight of concrete Horizontal seismic coefficient Vertical seismic coefficient
201.50 1.60 199.90 0.5 12.10
H= conc
Forces on the Pier at Point Distance from center Total Dead Load from superstructure (kN) Total Critical Live load excluding impact (kN)
2
16 kN/m³ 24 kN/m³ 0.150 0.075 Degree
Design of Pier Cap
Angle between the wall and earth Angle of internal friction of soil Angle of friction between soil and wall
m m m m m
0 32 16
A -2.50 2140.00 641.28
B 0.00 0.00 0.00
C 2.50 2140.00 641.00
Moment at the edge of the stem shaft
Due to dead load of the cap itself = Due to dead load from superstructure = Due to live load excluding impact = Due to Impact load =
427.38 5136 1539.0621 769.53105 7871.97
Hence Total Moment
Neutral Axis Factor Xc [m*Scbc/(m*Scbc+Sst)] = Lever Arm Z [1-Xc/3] = Moment of Resistance Factor R [[Scbc*Z*Xc]] = Assuming b=1 m Minimum Effective depth requireq deff_min [sqrt(M/R*b] =
Kn m Kn-m Kn-m Kn-m Kn-m Kn-m 0.29 0.90 2.65 1008.28 mm
Provided Over all Depth Cover provided (Top and Cover) Diameter of bar So, effective actual depth deff
2000 80 32 1824
Distance of the bearing center from the face of stem = Cap To be designed as Corbel Determination of Crobel Geometry Concrete grade 30 N/mm² Cover 40 mm h= 2.00 m d= 1.944 m av= 1 824 m 1.824
1200 mm
Width of Crobel (b) Total Vertical Load (V)
mm mm mm mm Ok
4.45 m 5562.28 KN
Pier_CAP+STEM
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
3
Calculation of Force as Strut and Tie Model
Calculation of x and z x= 0.1 d z= d-0.45x Cotb = av/z =
0.19 m 1.86 m 0.982
Sinb =
0.713
Cosb =
0.701
Fc = V/Sinb =
6000.06 KN
x=
160 mm
Now Ft =
ok
6577.30 KN 15120 23 mm22 15120.23
Area off Steel A S lA As= Area of Steel Considering Cantilever Area of Reinforcement required Ast [M/Z*deff*Sst] = Provide 32 mm bars at spacing Provided area of tensile reinforcement = Reinforcement at the bottom (compression side) Provide 25 mm bars at spacing
2
19937 mm 180.00 mm c/c, so nos of bars are 20106 mm2 OK AP1 AP6 200.00 mm c/c, so nos of bars are 2
11290 mm
Provided area of tensile reinforcement = Check for Shear Shear force at the critical section Due to dead load of the cap itself =
25
23
AP2
392.49 kN Pier_CAP+STEM
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
Due to dead load from superstructure = Due to live load excluding impact = Due to Impact load = Total Shear force Shear Stress developed, tau = V/(B*D) Allowable shear stress for the section (IRC:21-2000, Table 12A) = Percentage of longitudinal steel (tension+compression), pt = Allowable shear stress (IRC:21-2000, Table 12B) =
4
4280 kN 1282.55175 kN 641.275875 kN V= 6596.31763 kN 0.74115928 N/mm² 2.2 Section ok for shear 0.387 % tc = 0.264 < 0.741 Shear reinforcement is required Shear resisted by the longitudinal steel and concrete section = tc * B * d_eff = 2141033 N Shear force to be resisted by shear reinforcement Vus = 4455284 N Providing 8 legs of 16 mm Ø bars The shear steel area Asv = 1608.50 mm² Spacing of bars Sst * Asv *d_eff / Vus = 125 mm c/c Check for shear at bearings Check shear at a distance 1.20 m from the face of the stem Total Depth of beam at the bearing = 1510 mm Effective Depth of beam at the bearing= 1414 mm Shear forces: Due to dead load of the cap itself = 160.85 kN Due to dead load from superstructure = 4280.00 kN Due to live load excluding impact = 1282.55 kN Due to Impact load = 641.28 kN Total V= 6364.68 kN Shear Stress developed, tau = V/(B*D) 0.95 N/mm² Allowable shear stress for the section (IRC:21-2000, Table 12A) = 2.20 Section ok for shear Percentage of longitudinal steel (tension+compression), pt = 0.499 % Allowable shear stress (IRC:21-2000, Table 12B) = 0.320 N/mm² Shear resisted by the longitudinal steel and concrete section = tc * B * d_eff = 2012711 N Shear force to be resisted by shear reinforcement Vus = 4351971 N Providing 8 legs of 16 mm Ø bars The shear steel area Asv = 1608.50 mm² Spacing of bars Sst * Asv *d_eff / Vus = 125 mm c/c AP3 Ski reinforcement i f 0 1% off gross sectional i l area off the h beam b Skin @ 0.1% 8117 mm²² For each side = 4058 mm² each side Providing 16 mm bars 5 layers mm c/c, hence, 6 nos each side Provided area at each side = 10 leged 12064 mm² each side OK AP4 Check for punching shear 12 mm AP5 Average depth of section at bearing, i.e. at 1.2 m from the stem face= 1489.8 mm All Allowable bl punching hi pressure, tau_p = kks(0.16*sqrt(fck)) (0 16* (f k)) Where, ks = the minimum of 1 and 0.5+bc = 1 bc = B/L = 1 hence, tau_p = 2.27 Total punching stress developed = tau_punch = V/Lo*D Where Lo = perimeter around the critical plane = 2*(2D+L+B) = 6369.18 mm Hence, tau_punch = 0.0002 N/mm² Which is < 2 2712 OK 2.2712
Pier_CAP+STEM
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
5 Ø 32 @ 180 mm c/c AP6
Summary of reinforcement of Pier Cap
Ø 32 @ 180 mm c/c AP1
Ø 16 @ 5 layers AP4 Ø 32 @ 180 mm c/c AP1 Ø 16 @ 125 mm c/c AP3
Ø 16 @ 5 layers AP4 Ø 25 @ 200 mm c/c AP2
Ø 12 @ 5 layers AP5 Ø 25 @ 200 mm c/c AP2
Design of Pier Stem Length of stem column (between the surfaces of the restrains) Diameter of column D Effective length of column (IRC:21-2000, 306.2.1) [ effective length factor 1.2 ] Forces on the Pier at Point from superstructure
Impact factor
A B Distance from center -2.5 0 Dead Load (kN) 1 2140.00 0.00 Live load (kN) 1.098 641.28 0.00 Analysis y and Design g of pier p Stem Dead Load Dead Load From Superstructure Dead Load due to pier cap Dead Load of Pier Stem Total Dead Load Breaking Force:( As Per IRC:6-2000, 214.2) A)) Brakingg force = 20% of the weight g of the design g vehicle (Class ( Height of deck surface from the pier cap= And this force acts along the bridge at 1.2m above the road level Total weight of the IRC Class A vehicle = Therefore braking force length = Moment Due to Breaking Force
Effect of buyoncy
L=
10500 mm 2600 mm 12600 mm
Le =
Total Load Total Load CG of Load (absolute) (incl. impact) wrt center, m C (excl. impact)
2.5 2140.00 641.00
4280.00 4280.00 1282.28 1407.72
0.000 -0.001
8560.0 kN 702.00 kN 1083.10 kN 10345 kN
3.3 m 15.00 m from base 700 kN 140 kN 2100 kN-m
[IRC:6-2000, 216.4 (a)]
Area of stem at top = Depth of submerged part of Pier = Volume of submerged part of pier = Net upward force due to buyoncy = Live Load Live Load Excluding Impact = which will act at eccentricity ('CG of Load wrt center) Critical moment due to live load eccentricity
Pier_CAP+STEM
5.309 9.00 47.78 -477.84
m² m m³ kN
2564.55 kN -0.001 m -1.379375 kN-m
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
6
Frictional force due to resistance of bearings (temperature effect)
Lateral force due to frictional resistance of bearings, And this force acts along the bridge at Moment due to temperature effect
138.36 kN 10.50 m from base of stem 1452.80 kN-m
Force due to water current Exposed height to water current perimeter Area exposed Maximum mean velocity m/sec Maximum velocity, Sqrt(2)*V, (IRC:6-2000,213.3), V = Shape factor for square end (IRC:6-2000, 213.2), K = Pressure intensity =0.5KV² (IRC:6-2000, 213.2) = Hence force due to water current = Moment due to water current Seismic Forces on Seismic Forces Due to back fill and Approach Slab are also considered. Horizontal seismic forces: Forces (kN) Lever Arm (m) Superstructure: 1284.00 10.50 Pier cap 105.30 9.50 Pier stem 162.46 4.25 Total 1551.76 Vertical seismic forces: Superstructure: 642.00 Pier cap 52.65 Pier stem 81.23 Total 775.88
Pier_CAP+STEM
9.00 36.76 2.2 3.11 0.66 3.1944 78.28 704.49
m m
kN kN-m
Moment (kN-m) 13482.00 1000.35 690.47 15172.82
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
7
Loads and Moment Calculation Vertical Horizontal load along Horizontal Moment along load, P traffic(Y-Y) load across traffic (Y-Y) traffic (XX)
Combination combination I Dry case, Non-seismic Increment factor for allowable stresses* Total Dead load 1 10345.10 10345 10 Live load 1 2564.55 Tractive/Braking force 1 140.00 140.00 2100.00 Frictional force 1 138.36 1452.80 Total 13049.65 278.36 0.00 3552.80 combination VI Dry case, Seismic Increment factor for allowable stresses* Non seismic forces Total Dead load Live load Tractive/Braking force Frictional force Seismic forces Total
1 1 1 1 1
10345 10 10345.10 2564.55 140.00
1 -1.38
-1.38 1.5
-1.38
140.00 2100.00 138.36 1452.80 775.88 1551.76 1551.76 15172.82 13825.53 1830.13 1551.76 18725.63 combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* Total Dead load 1 10345.10 Live load 1 2564.55 Tractive/Braking force 1 140.00 140.00 2100.00 Frictional force 1 138.36 1452.80 Buyoncy 1 -477.84 Water Current 1 78.28 Total 12571.81 278.36 78.28 3552.80 combination VI-a Flooded case,, Seismic Increment factor for allowable stresses* Total Dead load 1 10345.10 Live load 1 2564.55 Tractive/Braking force 1 140.00 140.00 Frictional force 1 138.36 Buyoncy 1 -477.84 1452.80 Water Current 1 78.28 Seismic forces 1 775.88 1551.76 1551.76 15172.82 Total 13347.69 1830.13 1630.04 16625.63 Maximum Loads 13825.53 1830.13 1630.04 18725.63
Pier_CAP+STEM
Moment across traffic (X-X)
15172.82 15171.44 1 -1.38
704.49 703.11
1.5 -1.38
704.49 15172.82 15875.94 15875.94
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Cap and Stem
Non Seismic Case
8
Seismic Case
Resultant Critical forces: Vertical Load, P = 13049.65 kN Horizontal Load, H = 289.16 kN Moment, M = 3621.71 kN.m Increment factor for allowable stresses* IRC:6-2000, 202.3 Sectional area of stem = (Ag) Let Provide main reinforcement 1.5 % of Sectional area Total Area of reinforcement Let Provide 32 mm dia bars. Provided Number of Bar 100 Provide in one row Spacing between the bars = 77 Cover provided Grade of Concrete and Steel same as in Pier Cap Let provided diameter of transverse reinforcement the diameter up to the line of reinforcement Dc So Area of Steel Provided (As) So Area of Concrete (Ac) Check for Section capacity of Stem Equivalent area of Section Ae = Ac+(1.5m-1)*As= Equivalent moment of inertia of section Ie = (PI*D^4/64) + (m-1)*As*Dc² / 8
13825.53 kN 2450.80 kN 24100.24 kN.m
5309291.6 mm² 79639.3738 mm² (AP7) mm 40 mm 12 2480 80424.7719 5228866.8
mm mm mm² mm²
6354813.6 mm² 4
2.7997E+12 mm
3
Ze = 2*Ie/D = Scc = P/Ae = Scb = M/Ze =
2153577520 mm 2.054 N/mm² 1.682 N/mm² 0.4420 <1 Satisfied
Scc = P/Ae = Scb = M/Ze =
2.176 N/mm² 11.191 N/mm² 0.9394 <1 Satisfied
(Scc/Sacc + Scb/Sacb) =
Check For Seismic Case
Check the section for shear Resultant critical horizontal force: Shear stress developed, tau = Percentage of longitudinal steel (as provided)= Allowable shear stress tc = Hence, No shear reinforcement required. Provide nominal. Provide 12 mm circular rings @
125 mm c/c
Diameter of ring (mm)
Provide
500 mm c/c
(AP9)
12 mm Support bar @
Ø 12 @ 500 mm c/c (AP9)
2450795 0.462 1.515 0.482
N N/mm² % N/mm²
Satisfied 2520 (AP8)
Ø 32 @ 77 mm c/c (AP7)
Ø 32 @ 77 mm c/c (AP7) Ø 12 @ 125 mm c/c (AP8) Ø 12 @ 125 mm c/c (AP8) 6 no
Ø 12 @ 125 mm c/c (AP8)
Ø 12 @ 125 mm c/c (AP8) Ø 12 @ 125 mm c/c (AP6A) Pier_CAP+STEM
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
1
2.0 Design of Substructure 2.1 Design of Pier Section of Pier A
B
1.48 TPL
1
2.500
2.500
212
2.00 4.45 BPL
210.00
HFL
210 5 210.5
LBL
203
SBL
201 50 201.50
7.50 2.45
10.50 2.60
12.10
1.60
1.60
FBL 13.40
199.9
7.40
22
MSL
193.700
FL 177.9 This prelimanry section is defined by considering hydrological analysis and geotechnical recommendation Material Properties Concrete grade Steel grade Allowable stress of steel in tension and shear Allowable stress of steel in direct compression Allowable compressive stress in concrete in flexure Allowable comp. stress in concrete in direct compression Modular ratio (m) Neutral axis factor k j The resisting moment coefficient R
Pier_Foundation
SBL = Stem Bottom Level FBL = Footing Bottom Level MSL = Maximum Scour Level (fck) (fe) Sst = Ssc = Scbc = Scc = m=
30 500 240 205 10.0 7.5 10 0.29 0.90 1.33
N/mm² N/mm² N/mm² N/mm² N/mm N/mm² N/mm²
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
2
IRC:21-2000, 303.2.1, Table 9,10 Levels High Flood Level Maximum Scour level for Pier Level of Deck Surface Thickness of Pier cap (overall Thickness)
210.5 203 215.5 2 212 201.5 1.6 199.9 0.5 12.10
Top level of pier cap (TPL)
Top level of Footing (SBL) Thickness of Footing/Cap Bottem level of Footing/Cap (FBL) Thickness of Bearing Hence the total height of Pier Soil Data & Seismic Data Unit weight of backfill soil Unit weight of concrete Horizontal seismic coefficient Vertical seismic coefficient
H= conc conc
Angle between the wall and earth Angle of internal friction of soil Angle of friction between soil and wall Length of stem column (between the surfaces of the restrains) Diameter of column D Effective length of column (IRC:21-2000, 306.2.1) [ effective length factor 1.2 ] Forces on the Pier at Point from superstructure
Impact factor
Distance from center Dead Load (kN) 1 Live load (kN) 1.098 Forces at bottom of Footing Dead Load Dead Load From Superstructure Dead Load due to pier cap Dead Load of Pier Stem
A -2.50 2140.00 641.28
m m m m m
16 kN/m³ kN/m³ 24 kN/m 0.150 0.075 Degree 0 32 16 10500 mm 2600 mm 12600 mm
L= Le =
Total Load Total Load CG of Load (absolute) (incl. impact) wrt center, m C (excl. impact)
B 0.00 2.50 0.00 2140.00 0.00 641.00
4280.00 4280.00 1282.28 1407.72
0.000 -0.001
8560 kN 702.00 kN 1083.10 kN 3807.74 kN
D d lload Dead d off ffooting ti
Total Dead Load Breaking Force:( As Per IRC:6-2000, 214.2) Braking force = 20% of the weight of the design vehicle (Class A) Height of deck surface from the pier cap= And this force acts along the bridge at 1.2m above the road level Total weight of the IRC Class A vehicle = Therefore braking force length = Moment Due to Breaking Force
Effect of buyoncy
m m m m
14153 kN
3.3 m 16.60 m from base 700 kN 140 kN 2324 kN-m
[IRC:6-2000, 216.4 (a)]
Volume of submerged part of pier = Net upward force due to buyoncy =
127.11 m³ -1271.12 kN
Pier_Foundation
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
3
Live Load Live Load Excluding Impact = which will act at eccentricity ('CG of Load wrt center) Critical moment due to live load eccentricity
2564.55 kN -0.001 m -1.379375 kN-m
Frictional force due to resistance of bearings (temperature effect) Lateral force due to frictional resistance of bearings, And this force acts along the bridge at Moment due to temperature effect
138.36 kN 12.10 m from base 1674.18 kN-m
(From S. Sir) Force due to water current Exposed height to water current perimeter Area exposed Maximum mean velocity m/sec Maximum velocity, Sqrt(2)*V, (IRC:6-2000,213.3), V = 2000 213 2) K = Shape factor for square end (IRC:6 (IRC:6-2000, 213.2), Pressure intensity =0.5KV² (IRC:6-2000, 213.2) = Hence force due to water current = Moment due to water current Seismic Forces on Seismic Forces Due to back fill and Approach Slab are also considered. Horizontal seismic forces: Forces ((kN)) Lever Arm ((m)) Superstructure: 1027.20 12.10 Pier cap 105.30 11.10 Pier stem 162.46 5.85 Footing 571.16 0.80 Total 1866.13 Vertical seismic forces: Superstructure: 642.00 Pier cap 52.65 Pier stem 81.23 Footing 285.58 Total 1061.46
Pier_Foundation
10.60 43.29 2.2 3.11 0 66 0.66 3.1944 92.19 977.24
m m
kN kN-m
Moment ((kN-m)) 12429.12 1168.83 950.42 456.93 15005.30
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
4 210.5
HFL 16.8
203
LBL
199.90
3.10
1.50 6.20
193.7
MSL 4.9
22
15.80 188.8
level of fixity
10.90 177 90 177.90
Foundation level
0.7 3.00 13.40
1
7.40 3.00 Length of Pile cap Along Brodge Axis = Length of Pile Cap Across Bridge Axis = Depth of Fixity from maximum Scour Level =
0.7 7.40 m 13.40 m 4.9 m
(IS 2911 part I section II, Appendix C, Adopting Max value) Di Diameter off Pil Pile = Depth of Pile = No of Pile in one row = (Along Bridge Axis) No of Row = Total No of Pile (n) = Embedded length of Pile = Thickness of Pile Cap = 709 5 IRC 78:2000 Cl 709.5
Factor of Saftey FS = IRC 78:2000 Cl 709.3 offset of pile cap from the outer face of outermost pile = Center to center distance of the piles Along Bridge Axis (Xi) = Across Bridge Axis (Yi) =
Pier_Foundation
1m 22.00 m 3 5 15 15.80 1.60 m OK 2.5 0.20 m Ok 3.00 m 3.00 m
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
5
6.70 m 6.70 m
Width of Pile Group (Outer Surface of The piles) along Axis (B) = Width of Pile Group (Outer Surface of The piles) across Axis (L) =
44.89 m
Area Enclosed by pile Groups (Ag) = Loads and Moment Calculation
2
Vertical load, Horizontal load along Horizont Moment along P traffic(Y-Y) al load traffic (Y-Y) across traffic (XX)
Factor Combination combination I Dry case, Non-seismic Increment factor for allowable stresses* Total Dead load 1 14152.84 Live load 1 2564.55 Tractive/Braking force 1 140.00 140.00 2324.00 Frictional force 1 138.36 1674.18 Total 16857.39 278.36 0.00 3998.18 combination VI Dry case, Seismic Increment factor for allowable stresses* Non seismic forces Total Dead load Live load Tractive/Braking force Frictional force Seismic forces T l Total
1 0.5 0.5 0.5 1
14152.84 1282.28 70.00
Non Seismic case Dry (comb. I) Flooded (comb. I-a) Seismic case Dry (comb. VI) Flooded (comb VI-a) Max Loads:
force (kN)
1 -1.38
-1.38 1.5
-0.69
70.00 1162.00 69.18 837.09 1061.46 1866.13 1866.13 15005.30 16566 58 16566.58 2005 31 1866.13 2005.31 1866 13 17004 39 17004.39 combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* Total Dead load 1 14152.84 Live load 1 2564.55 Tractive/Braking force 1 140.00 140.00 2324.00 Frictional force 1 138.36 1674.18 Buyoncy 1 -1271.12 Water Current 1 92.19 92 19 Total 15586.27 278.36 92.19 3998.18 Flooded case, Seismic Increment factor for allowable stresses* combination VI-a Total Dead load 1 14152.84 Live load 0.5 1282.28 Tractive/Braking force 0.5 70.00 70.00 Frictional force 0.5 69.18 Buyoncy 1 -1271.12 1674.18 Water Current 1 92.19 1 1061.46 1866.13 1866.13 15005.30 Seismic forces Total 15295.46 2005.31 1958.32 16679.48 Summary of Loads Moment Particular/Load cases Vertical Horizontal force (kN)
Moment across traffic (X-X)
Moment Along Axis (kN.m)
-1.38
977.24 977 24 975.86 1.5 -0.69
977.24 15005.30 15981.85
Across Axix (kN.m)
16857.39 15586.27
278.36 293.23
3998.18 3998.18
-1.38 975.86
16566.58 15295.46 16857.39
2739.28 2802.90 2802.90
17004.39 16679.48 17004.39
15004.61 15981.85 15981.85
Pier_Foundation
15005.30 15004 61 15004.61 1
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
6
Maximum load on individual piles Maximum and Minimum Load is given by V max = [V/n] + (Mxx*Xmax)/ Xi² + (Myy*Ymax)/ Yi² V min = [V/n] - (Mxx*Xmax)/ Xi² - (Myy*Ymax)/ Yi²
Moment of Inertia of Piles Xi²=
90.00 m²
Yi²=
270.00 m²
Maximum Load will be on outermost pile So, X max = Y max = Particular/Load cases Vertical force (kN)
3.00 6.00
Vmax
Vmin
Non Seismic case Dry (comb. I) 16857.39 1257.07 Flooded (comb. I-a) 15586.27 1194.04 Seismic case Dry (comb. VI) 16566.58 2004.69 Flooded (comb VI-a) 15295.46 1930.83 Design of Pile Concrete grade Steel grade Allowable stress of steel in tension and shear Allowable stress of steel in direct compression Allowable compressive stress in concrete in flexure Allowable comp. stress in concrete in direct compression Modular ratio (m)
Recommended Pile Capacity from soil Investigation
H max
990.58 884.13
18.56 19.55
1650 1650
OK OK
204.19 108.56
182.62 186.86
2475 2475
OK OK
(fck) (fe) Sst = Ssc = Scbc = Scc = m=
30 500 240 205 10.00 7.5
k j
0.90
g moment coefficient The resisting
R
1.33
Non Seismic Seismic
Pier_Foundation
N/mm² N/mm² N/mm² N/mm N/mm² N/mm² N/mm²
10
Neutral axis factor
Cover Horizontal Force Per Pile
Remark
0.29
80 mm 19.5 kN 186.9 kN
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
7
Pier_Foundation
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
8
2.74E+04 MN/m 4.91E-02 m4
Elasticity of Concrete, Moment of Inertia, Soil Type
2
Cohensionless Soil
Calculation for Cohesionless Soil
Calculation for Cohesive Soil
Calculate
Not Applicable
ηh
5 MN/m3
(Table 3 IS 2911) Stiffness Factor T Embedded length of Pile (Le)
L1
K or ηh 3.06 m 15.80 m
Lf/T
2 6.12
15.80 m
L1
3.10 m
L1/R
0.72
Lf/R
1.950
Lf
Moment MF Fixed End Moment,
8.3 m Seismic Case
Non Seismic Case 90 15 90.15
Reduction Factor, m
861 67 KNm 861.67
0.85
Actual maximum moment, M Maximum Axial Force (kN)
4.3 m
Embedded length of pile, Le
1.0
Lf
4
Relative Stiffness Factor, R
3.10 m
L1/T
3 20000 kN/m
k1 ((IS :2911/Part1/Sec2-2010/Table 4))
0.85 (IS :2911/Part1/Sec2-2010/Fig. 3, Fixed Head /Amendent)
76.62
732.42 KNm
1257.07
2004.69
Design For Non Seismic Case
Sectional area of pile = (Ag) Let Provide main reinforcement 1.8 % of Sectional area Total Area of reinforcement Let Provide 20 mm dia bars. Provided Number of Bar 46 Provide in one row Spacing between the bars = 68 Cover provided Let provided diameter of transverse reinforcement the diameter up to the line of reinforcement Dc So Area of Steel Provided (As) So Area of Concrete (Ac) Check for Section capacity of Stem Equivalent area of Section Ae = Ac+(1.5m-1)*As= Equivalent moment of inertia of section Ie = (PI*D^4/64) + (m-1)*As*Dc² / 8
785398.2 mm² 14137.1669 mm² (AP5) mm 80 10 840 14451.3262 770946.8
mm mm mm mm² mm²
973265.4 mm² 6.535E+10 mm
3
130690254 mm 1.292 N/mm² 0 586 N/mm² 0.586 N/ ² 0.2308 <1 Satisfied 0.56 Satisfied
Ze = 2*Ie/D = Scc = P/Ae = S b = M/Z Scb M/Ze = (Scc/Sacc + Scb/Sacb) = (Scc/Sacc + Scb/Sacb) = Seismic Case: Summary of reinforcement of Pile Section 46 nos of 20 mm dia bars Provide
Volume of tie of 10 mm tie Number of Ties per meter of pile = & Spacing =
PLP1 mm
2
2356194.49 mm
3
207261.7 mm 12
3
Ast provided = 14452.00 Lateral Ties Minimum volume of lateral reinforcement per meter length of pile
84.00
Pier_Foundation
4
ok 0.3 %
mm c/c
PLP2
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
9
Summary of reinforcement of Pile Section
Ø 20 @ 46 Nos PLP1
Ø 10 @ 84 mmc/c PLP2 Design of Pile Cap From Face
1.3 1.70 3.00
Bending Moment at the face of Column = Neutral Axis Factor Xc [m*Scbc/m*Scbc+Sst] = Lever Arm Z [1-Xc/3] = Moment of Resistance Factor R [Scbc/2*Z*Xc] = Minimum Effective depth requireq deff_min [sqrt(M/R*b] b] = ff i [sqrt(M/R
1271.63 kN-m 0.29 0.90 1.33 979 131 mm 979.131
Provided Over all Depth Cover provided (Top and Cover) So, effective actual depth deff
1600.00 mm 75 mm 1525 mm Ok
Area of Reinforcement required Ast [M/Z*deff*Sst] =
3852.05 mm
Pier_Foundation
2
Rapti Bridge Design 5_3_Pile.xls
Design of Pier Foundation
10
Provided Reinforcement Nos Reinforcement Tensile Reinforcement (Bottom) Bothway Top Bar Top Reinforcement Bothway f
Dia of Bar 25
Spacing (mm) c/c provided 120
mm² > Ast required OK
mm² %
Nos 62 112
OK
1.0 tau_p =
Punching stress developed =
700 mm spacing
PPC3+4
mm c/c
1600.00 mm
So, allowable punching Stress
Providing Nominal Chair Bar 10 dia @
Level
62.00 PPC1+2 112.00
9
Ast Provided (Bottom) 4417.86 Min 0.12 % of gross area 25 mm 120 Ast Provided (Top) 4090.62 0.26824
Check For Punching Stress Depth of Section = Allowable punching pressure, tau_p = ks(0.16*sqrt(fck)) Where, ks = the minimum of 1 and 0.5+bc = bc = B/L = 1
Total
Per meter
0.876 N/mm
2
0.20 N/mm OK
2
PPC6
Ø 10 @ 700c/c PPC6 Ø 25 @ 120c/c PPC3 & PPC4
3 Nos 10 mm bar Periphery PPC5
Ø 25 @ 120c/c (PPC1 & PPC2)
Ø 20 @ 46 Nos PLP1
Ø 10 @ 84 mmc/c PLP2
Pier_Foundation
Rapti Bridge Design 5_3_Pile.xls
Re
Bar Bending Schedule
Bar Bending Schedule of Abutment Cap Shape
Label
AC1
Dia
10870
Length( Unit Weight Weight(Kg) m) (Kg)/m
Nos
12
28
10.870
0.888
270.215
10
62
5.310
0.617
203.351
8
4
16.000
0.395
25.253
2
Total Weight
1770 AC2
835 2x50
600
AC3
Pitch 75 mm bothways, 2 layers
500
Total No of Abutment
498.819 997.638
Bar Bending Schedule of Abutment Stem Shape
Label
Dia
Length (m)
Nos
Unit Weight Weight(Kg) (Kg)/m
450 AS1
8750
25
110
9.650
3.853
4090.341
8750
20
85
9.65
2.466
2022.860
16
56
23.540
1.578
2080.626
450 450 AS2
450 10870 AS3
900
900
10870 Total No of Abutment
2
Total Weight
Abutment Detailing
8193.827 16387.654
Rapti Bridge Design 5_3_Pile.xls
Bar Bending Schedule
Bar Bending Schedule of Abutment Back Wall Shape
Label
Dia
Length (m)
Nos
Unit Weight Weight(Kg) (Kg)/m
250 AB1
4400
25
53
6.47
3.853
1321.356
20
43
5.42
2.466
574.761
12
11
22.24
0.888
217.195
16
41
1.82
1.578
117.775
10
82
0.65
0.617
32.861
10
41
0.4
0.617
10.111
570 1250
250 AB2 4600 570
10870 AB3 250
AB4
220
500
250
300
700 100 500
AB5 75
75
250
AB6 75
75
AB7
10920
20
1
10.92
2.466
26.930
AB8
10920
16
3
10.920
1.578
51.706
Total No of Abutment
2
Total Weight
Abutment Detailing
2352.696 4705.392
Rapti Bridge Design 5_3_Pile.xls
Bar Bending Schedule
Bar Bending Schedule of Pile per Abutment / Pile Cap Shape
Label
Dia
Length (m)
Nos
Unit Weight Weight(Kg) (Kg)/m
200 APL1
21350
APL2
25.00
360.00
21.6
3.853
29894.365
10.00
3840.00
2.74
0.617
6484.447
1350
25
112
10.0
3.853
4294.184
1350
25
62
15.9
3.853
3805.809
1350
25
112
10.0
3.853
4294.184
1350
25
62
15.93
3.853
3805.809
10
3
41.8
0.617
77.314
10
22
34.32
0.617
465.511
50 dia =
APC1
840
1350 7250
APC2
1350 13230
APC3
7250
1350
APC4
1350
13230
200
APC5
13230
7270
200
400
18 nos 200
1316.0
APC6
400
19 nos
bothway @ spacing
700.00 mm c/c
Total No of Cap
2
Total Weight
Abutment Detailing
53121.623 106243.25
Rapti Bridge Design 5_3_Pile.xls
Bar Bending Schedule
Bar Bending Schedule of Pier Cap Shape
Label
AP1
400
AP2
400
7340
Dia
400
Nos
Length
Unit Weight (Kg)/m
Weight(K g)
32
25
8.14
6.321
1286.40
25
23
8.54
3.858
757.84
16
59
19.300
1.580
1799.54
16
5
53.56
1.578
422.678
400 2600
2570
4290 8 Legs Average H= 840
AP3
AP4
Averaage 4370
2520
1840
7340 10 nos
AP5
7340
12
75
7.34
0.888
488.742
AP6
7340
32
24
7.34
6.313
1112.159
Total No of Pier
9
Pier Detailing
Total Weight
5867.3631 52806.268
Rapti Bridge Design 5_3_Pile.xls
Bar Bending Schedule
Bar Bending Schedule of Pier Stem Shape
Label
AP7
Dia
11100
Nos
Length
Unit Weight (Kg)/m
Weight(K g)
32
100
11.5
6.321
7269.60
12
68
8.217
0.889
496.69
12
34
2.644
0.889
79.91 7846.1998 70615.799
400 150
AP8 Dia =
AP9
2520 50
2544
Total No of Pier
9
Pier Detailing
Total Weight
Rapti Bridge Design 5_3_Pile.xls
Bar Bending Schedule
Bar Bending Schedule of Pile per Abutment / Pile Cap Shape
Label
Dia
Length (m)
Nos
Unit Weight (Kg)/m
Weight (Kg)
200 PLP1
23460
PLP2
690.00
23.7
2.466
40260.89
10.00
4220.00
2.74
0.617
7126.137
1450
25
112
10.15
3.853
4380.50
1450
25
62
16.13
3.853
3853.59
1450
25
112
10.15
3.853
4380.50
1450
25
112
16.13
3.853
6961.33
10
3
41.56
0.617
76.87
10
22
36.32
0.617
492.64
50 dia =
PPC1
20.00
840
1450 7250
PPC2
1450 13230
PPC3
1450
PPC4
1450
7250
13230
7300 2200
13280
PPC5
19 nos
200
400
200
1416
APC6
400
18 nos
bothway @ spacing
700.00 mm c/c
Total No of Pier
9
Pier Detailing
Total Weight
67532.449 607792.04
Rapti Bridge Design 5_3_Pile.xls