Substructure_Final_.pdf

Section of Abutment 0.25 0.3 1.00

288.3 Deck Level0.2

1.0 A6 A7 0.5 2.30.5

A5 0.180.0 A2 1

0.0 0.1 284 HFLA3

3.005.30

Y 0.6294 A1 0.1706 280.32 MSL3.438 A4

x

A 279.52 SBL1.20 0.20

1.70 A8T 277.82 FBL

This prelimanry section is defined by considering SBL = Stem Bottom Levelhydrological analysis and geotechnical recommendation FBL = Footing Bottom Level

MSL = Maximum Scour LevelMaterial PropertiesConcrete grade (fck) 20 N/mm²Steel grade (fe) 500 N/mm²Allowable stress of steel in tension and shear Sst = 240 N/mm²Allowable stress of steel in direct compression Ssc = 205 N/mm²Allowable compressive stress in concrete in flexure Scbc = 6.67 N/mm²Allowable comp. stress in concrete in direct compression Scc = 5 N/mm²Modular ratio (m) m = 11Neutral axis factor k 0.32

j 0.89The resisting moment coefficient R 0.95IRC:21-2000, 303.2.1, Table 9,10LevelsHigh Flood Level 284 mMaximum Scour level for abutment 280.32 mTotal depth of longitudinal Girder including Slab 2.3 mProvided Clear free board 2.00 mLevel of Deck Surface 288.30 mThickness of abutment cap 1.00 mTop level of Footing (SBL) 279.52 m Thickness of Footing/Cap 1.70 mBottem level of Footing/Cap (FBL) 277.82 mThickness of Bearing 0.18 mHence the total height of abutment H= 8.78 m

2.0 Design of Substructure2.1 Design of Abutment

Substructure Kamala Khola_Bridge Project

As per IRC : 6-2000, 217.1 for Equivqlent live load Surcharge1.2 m

Equivalent Height of Abutment H eq= 9.98 mLength of Abutment L= 7.2 mSpan Length 36.95 mApproach Slab DiamensionsThickness of approach slab 0.2 mLength of Approach Slab 3.00 mWidth of Approach Slab 7.2 mBallast WallWidth of Ballast wall 0.3 mLength of Ballast wall 7.2 mWing WallThickness of wing wall 0.4 mSoil Data & Seismic DataUnit weight of backfill soil γ 16 kN/m³Unit weight of concrete ω_conc 24 kN/m³Horizontal seismic coefficient αΗ 0.120Vertical seismic coefficient αν 0.060

DegreeAngle between the wall and earth α 0Angle of internal friction of soil φ 30Angle of friction between soil and wall δ 16Analysis and Design of Abutment StemArea and C.G Calculation with respect to bottom of stem point A

Symbol Area (m2) CG-X CG-Y Weight (KN)A1 2.63 0.15 4.39 455.16A2 1.00 0.80 5.80 172.80A3 5.830 0.78 2.65 1007.42A4 0.53 1.27 1.77 91.58A5 0.00 0.00 7.78 0.00A6 0.00 0.00 8.28 0.00A7 0.13 -0.13 8.33 21.60Total 10.12 1748.56C.G from A 0.6294 3.438Position of C.G From Superstructure Load Point 0.1706


Forces on the AbutmentTotal Dead Load from superstructure 2222.4 KNTotal Critical Live load including impact 1302.9 KNEarth Pressure force (Including live load surcharge) [IRC:6-2000, 217.1]Total Static earth pressure = 0.5* γ * Heq² * tan²(45° - φ/2)*L = 411.89685 KNWhich act at a distance from abutment base (0.42*Heq) 4.1916 mEffect of buyoncy [IRC:6-2000, 216.4 (a)]

Area of stem at top = 8.64 m²Depth of submerged part of abutment = 4.48 mArea of stem at base = 10.08 m²Area of stem at HFL = 9.8572075 m²Volume of submerged part of abutment = 44.659345 m³

Taking 1/2 of the volume, Net upward force due to buyoncy = -223.2967 kNFrictional force due to resistance of bearings (temperature effect)Coefficient of thermal expansion of concrete (C) = 0.000009Length of main girders (L) 36950 mmWidth of girder (a) 400 mmAssume width of elastomeric bearing (parallel to span) (b) 300 mmAssume thickness of elastomeric bearing (T) 50 mmDifferential temperature in celcius (dt) 30 degreeNumber of main girders = 3Assume Shear modulus of elastomer (G) 1.2 N/mm² (range 0.6 to 1.2)Elongation of the girder (D) = C*L*dt 9.9765 mmPlan area of the bearing (A) = 120000 mm²Longitudinal force transmitted to the pierF = G*A*D / T = 28.73232 kN per bearingTotal force from all bearings 86.20 kNLateral force due to frictional resistance of bearings, 86.20 kN(From S. Sir)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 9.98 m from baseTotal weight of the IRC Class A vehicle = 543.29 kNTherefore braking force length = 54.329 kNSeismic Forces on Abutment [IRC : Seismic Forces Due to back fill and Approach Slab are also considered.Horizontal seismic forces:

Superstructure: 266.69 kNAbutment: 209.83 kNBackfill soil mass: 49.43 kNThis forces will act at 0.5 Heq 4.99 m

Vertical seismic forces:Superstructure: 133.34 kNAbutment: 104.91 kN


Loads and Moment CalculationThe transverce forces and moments are not calculated since it will not be critical due to high moment of inertia.

ParticularLoad Coefficient IRC:6-2000, 202.3

combination I Dry case, Non-seismic Increment factor for allowable stresses* 1Superstructure dead load 1 2222.40 0.80 1777.92Live load 1 1302.87 0.80 1042.30Abutment 1 1748.56 -0.63 -1100.57Soil mass 1 411.90 4.19 1726.51Tractive/Braking force 1 54.33 9.98 542.20Frictional force 1 86.20 6.30 543.04Total 5273.84 552.42 20.47 4531.40

combination VI Dry case, Seismic Increment factor for allowable stresses* 1.5Non seismic forces

Superstructure dead load 1 2222.40 0.80 1777.92Live load 0.5 651.44 0.80 521.15Abutment 1 1748.56 -0.63 -1100.57Soil mass 1 411.90 4.19 1726.51Tractive/Braking force 0.5 27.16 9.98 271.10Frictional force 0.5 43.10 6.30 271.52Additional seismic forcesSuperstructure 1 133.34 0.800 266.69 6.48 1834.82Abutment 1 104.91 -0.629 209.83 3.44 655.38Soil mass 1 49.43 4.99 246.64Total 4860.66 1008.10 6204.47

combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* 1Superstructure dead load 1 2222.40 0.80 1777.92Live load 1 1302.87 0.80 1042.30Abutment 1 1748.56 -0.63 -1100.57Soil mass 1 411.90 4.19 1726.51Tractive/Braking force 1 54.33 9.98 542.20Frictional force 1 86.20 6.30 543.04Buyoncy 1 -223.30Total 5050.54 552.42 20.47 4531.40

combination VI-a Flooded case, Seismic Increment factor for allowable stresses* 1.5Non seismic forces

Superstructure dead load 1 2222.40 0.80 1777.92Live load 0.5 651.44 0.80 521.15Abutment 1 1748.56 -0.63 -1100.57Soil mass 1 411.90 4.19 1726.51Tractive/Braking force 0.5 27.16 9.98 271.10Frictional force 0.5 43.10 6.30 271.52Buyoncy 1 -223.30Additional seismic forcesSuperstructure 1 133.34 0.80 266.69 6.48 1834.82Abutment 1 104.91 -0.63 209.83 3.44 655.38Soil mass 1 49.43 4.99 246.64Total 4637.36 1008.10 6204.47

Maximum Loads 5273.84 1008.10 6204.47

Increment factor for allowable stresses* IRC:6-2000, 202.3

Vertical force (kN)

Horizontal Lever arm, (m)

Horizontal force

(kN)

Vertical Lever arm,

(m)

Moment (kN.m)


2.1.1 Design of abutment stem SectionAbutment Stem will be designed as compression member with uniaxial moment.Overall Thickness of Stem at base D = 1400 mmLength of the abutment L = 7200 mmGross cross sectional area of the stem Ag = 10080000 mm²percentage of longitudinal tensile reinforcement pst 0.25 % the percentage of longitudinal compressive reifnrocement psc 0.11 %Percentage of steel to be provided as per IRC:21-2000, 306.2.2 0.3 %Total percentage of longitudinal reinforcement = 0.36 % OK

Then the initial total area of reinforcement Asc = 36288 mm²Net area of concrete Ac = 10043712 mm²Let the effective cover (referring to the CG of bars) cover (d')= 65 mmHence the effective depth d_eff = 1335 mm

Moment of inertia I = 1.428.E+12 mm4

Section modulus Z = 2.139.E+09 mm³Radius of gyration SQRT(I/Z*L) k = 385 mmHeight of the abutment (upto abutment cap) 6300 mmEffective length (height) factor (IRC:21-2000, 306.1.2, Table 13) = 1.75Effective height of the abutment 11025 mmRatio of Effective length : Radius of gyration = 28.61Hence it is treated as a Short ColumnThe direct comp. stress,Scc_cal = P/(Ac+1.5*m*Asc) N/mm²The comp. stress in bendingScbc_cal = M/Z N/mm²Interaction Condition to be satisfied:

[Scc_cal/Scc] + [Scbc_cal/Scbc] = <1

Comp. Stress Non-Seismic Case Seismic Case [Scc_cal/Scc] + [Scbc_cal/Scbc] ConditionScc_cal = 0.50 0.46 0.4 <1 Satisfied

Scbc_cal = 2.12 2.90 0.4 <1 Satisfied

Reinforcement Calculation

Reinforcement Area (mm2) Bar dia (mm) Nos Spacing (mm) c/cProvided Nos

Tensile reinforcement (AS1+AS2) 25200 32 32 150 AS1+AS2 49

11088 25 23 150 AS3+AS4 49

Total area of provided tensile reinforcement = Ast = 25736 mm²Total area of provided compressive reinforcement = Asc = 11290 mm²Total provided area of longitudinal steel = 37026 mm²

0.367 % OKCheck For ShearCritical shear force at the base 552422.81 NEffective area of the section 10080000 mm²Shear Stress 0.055 N/mm²Permissible Shear Stress 0.258 N/mm² OK

[IRC:21-2000, Table 12B]

Compressive Reinforcement (AS3+AS4)


Check For Cracked or Uncracked SectionFor uncracked section (Scbc_cal - Scc_cal) < 0.25*(Scc_cal + Scbc_cal)Case (Scbc_cal - Scc_cal) 0.25*(Scc_cal + Scbc_cal) Section isNon seismic condition: 1.62 0.65 CrackedSeismic condition: 2.44 0.84 CrackedAs The Section is cracked Reinforcement and section should be checked for cracked conditionCritical Neutral axis x 607.34 mmThe resultant Stress Scb 2.632 N/mm²Stress in tension reinforcement:Ss = m*Scb*(D-d'-x)/x = 34.69 N/mm² < 240 OKStress in compression reinforcement:Ssc = 1.5m*Scb*(x-d')/x = 38.78 N/mm² < 205 OK

Curtailment of BarAssume the amount of reinforcement to be curtailed 50 %And curtailment will be at 3.50 m from the base of stemThickness of stem at point of curtailment 1267.9 mmEffective depth of stem 1202.9 mmAmount of longitudinal Reinforcement Asc = 18144 mm²Net area of concrete Ac = 9129056.6 mm²Area of tensile reinforcement = Ast = 12868 mm²Area of provided compressive reinforcement = Asc = 5645 mm²

I = 1.044E+12 mm4

Forces and Moment at curtailment Z = 1.736E+09 mm³Particular

Non seismic forcesSuperstructure dead load 1 2222.40 0.80 1777.92Live load 0.5 651.44 0.80 521.15Abutment 1 833.77 0.60 502.12Soil mass 1 805.23 2.72 2191.51Tractive/Braking force 0.5 27.16 6.48 176.03Frictional force 0.5 43.10 2.80 120.68Additional seismic forcesSuperstructure 1 133.34 0.800 133.34 2.98 504.04Abutment 1 50.03 0.629 50.03 3.36 199.37Soil mass 1 48.31 2.72 131.49Total 3890.98 1107.2 6124.30

The direct comp. stress,Scc_cal = P/(Ac+1.5*m*Asc) = 0.413 N/mm²The comp. stress in bendingScbc_cal = M/Z = 3.53 N/mm²So,

[Scc_cal/Scc] + [Scbc_cal/Scbc] = 0.612 <1 OK

The condition of tensile stress at the extreme fibre of concrete:(Scbc_cal - Scc_cal) < 0.25*(Scc_cal + Scbc_cal) 3.114 > 0.985

Section is CrackedAs The Section is cracked Reinforcement and section should be checked for cracked conditionCritical Neutral axis x 449.18 mmThe resultant Stress Scb 2.638 N/mm²Stress in tension reinforcement:Ss = m*Scb*(D-d'-x)/x = 44.50 N/mm² < 240 OKStress in compression reinforcement:Ssc = 1.5m*Scb*(x-d')/x = 37.23 N/mm² < 205 OK


Horizontal force

(kN)

Vertical Lever arm,

(m)

Moment (kN.m)

Vertical force (kN)


Check for shear

Critical shear, V = 1107175 NEffective area, A = 9129056.6 mm²

Tensile reinforcement area = 12867.964 mm²Compression reinforcement area = 5645.0493 mm²Hence total reinforcement area = 18144 mm²Percentage of steel provided = 0.199 %

Shear stress developed, tau= 0.1213 N/mm²Permissible shear stress with longitudinal reinforcement = 0.204 N/mm²

OKReinforcement Area (mm2) Bar dia (mm) Nos Spacing (mm) c/c calculated/provided

Tensile reinforcement 12868 32 16 480 300 AS1Compressive Reinforcement 5645 25 12 650 300 AS3Maximum allowded spacing is 300 mm Hence provide at sapcing of 300 mm

Let the percentage of distribution bars be 10 % of the total longitudinal reinforcement

Hence, area of distribution bars = 3702.6026 mm²Let's use bars of 12 mm Unit area = 113.1 mm²Total number of distribution bars on each face of the stem = 17 nos

Spacing @ 330 mm c/cProvided spacing 300 mm and bar dia is 12 mm (AS5)

No of Bar 17 on each face of stem

Distribution Bar calculation


AS5 AS5

AS1 Ø 12 @ 300 c/c AS1+AS2 Ø 12 @ 300 c/c

Ø 32 @ 300 c/c AS3 Ø 32 @ 150 c/c AS3+AS4

Ø 25 @ 300 c/c Ø 25 @ 150 c/c

Above curtailment Below curtailment

AS3AS1 Ø 25 @ 300 c/cØ 32 @ 300 c/c Height of curtailmnet

AS5Ø 12 @ 300 c/c AS3+AS4

AS1+AS2 Ø 25 @ 150 c/cØ 32 @ 150 c/c

2.1.2 Design of Abutment CapCalculation of Vertical Load

Superstructure Dead Load 2222.4 KNLive Load Including Impact 1302.9 KNTotal Load 3525.3 KNTotal Load per Girder 1175.1 KNNo of Longitidunal Girder 3

Depth of Abutment Cap D = 1000 mmCheck For Punching Stress:

Bearing Size provided L= 400 mmB= 300 mm

Allowable punching Stress = τau_p = ks(0.16*sqrt(fck))

Where ks is minimum of 1 and 0.5 + bc and bc = B/L 0.75So, ks = 1

Allowable punching Stress tau_p = 0.716 N/mm²Total Punching Stress Developed τau_developed = V/Po*Dwhere Po is perimeter of affected Area = 2 (2D+L+B)

Po 5400 mmSo, Punching Stress Developed τau_developed = 0.2176 N/mm²

< 0.716 N/mm² OkAs depth is safe for punching no additional reinforcement is required. Providing nominal reinforcement.

Reinforcement Bar dia (mm) Nos Spacing (mm) c/c provided LevelReinforcement along length of cap 16 20 200 AC1Stirrups around the cap 12 36 200 AC2And Provide 2 layers of 10 mm bar mesh of

length L: 550 mm AC3Breadth : 450 mm

Summary of reinforcement of abutment stem Section


Ø10mm 2 layers of bar mesh AC3Ø 12 @ 200 mmc/c AC2

Ø 16 @ 200 mmc/c AC1

Ø 12 @ 200 mmc/c AC2

Ø 16 @ 200 mmc/c AC1 Ø10mm 2 layers of bar mesh AC3

2.1.3 Design of Back Wall/DirtWallTotal Horizontal force due to earth pressure including live load surcharge is given by

0.5.γs.(height of ballast wall+1.2(eq live load surcharge)) 2.tan2(45°-φ/2)*L= 234.91 KN

which acts at a distance 0.42H from backwall base of 1.47 mTotal Seismic earth pressure Including live load surcharge is given by

(0.5* g Ka_dyn*H² *L) =Horizontal component of this force = 28.19 kNThis force acts at 0.5*H, hence lever arm = 1.75 m

Self weight of backwall 119.2 kNthese act at a distance from backwall toe of 0.15 m

Moment due to earth pressure about abutment base 345.32 kN.mMoment due to seismic forces 49.33 kN.mMoment due self weight 17.8848 kN.mTotal Moment about backwall toe 412.54 kNmTotal Base Shear 263.10 kNProviding 40 mm cover and total thickness of ballast wall is 300 mm & dia of main bar & Distribution bar are 32 mm & 12 mm respectivelySo, available effective depth = 212 mm

Critical neutral axis, xc = Scbc*deff/((Sst/m)+Scbc) 49.62 mmLever arm , Z = deff-xc/3 195.46 mm

Required area of tensile steel (M/Z*Sst) = 8794.09 mm²

So, No of main bar 12 @ spaicng 650 mm c/c >300 mmProvided Reinforcement

Reinforcement Dia of Bar Spacing (mm) c/c provided Nos LevelMain Bar (Back Face) 32 300 25 AB1

12 300 9 AB3Compression Bar (Front Face) 25 300 25 AB2

Summary of reinforcement of abutment Cap Section

Distribution Bar (Horizontal bar at each face)


250 300

Ø 20 AB7Ø 32 @ 300 mmc/c AB1

Ø 12 @ 300 mmc/c AB3250

Ø 10 AB5Ø 25 @ 300 mmc/c AB2

250 Ø 10 AB6

Ø 16 AB8

Ø 16 AB42.1.3 Design of Abutment Foundation

0.25 0.3 1

0.21.0 A6 A7 0.5 2.3

0.5A5 0.18

0.0 A2 1

0.0 0.1A3 8.78

3.00 10.48

5.30Y A1 3.63

0.28 A4x 2.76

A1.20 0.2

1.70 A8

3.25 1.40 2.75 T7.40

Area and C.G Calculation with respect to Foundation at point T

Symbol Area (m2) CG-X CG-Y Weight (KN)A1 2.63 4.00 6.09 455.16A2 1.00 3.35 7.50 172.80A3 5.83 3.40 4.35 1007.42A4 0.53 2.88 3.47 91.58A5 0.00 4.15 9.48 0.00A6 0.00 4.15 9.98 0.00A7 0.13 4.28 10.03 21.60A8 12.58 3.70 0.85 2173.82Total 22.70 3922.39

Summary of reinforcement of Back Wall


C.G from T 3.63 2.762 mPosition of C.G From Superstructure Load Point 0.28 mPosition of superstructure load point From toe= 3.35 mHeight of Abutment (H) 8.78 mHeight of Abutment Including Footing (H') 10.48 mLength of Abutment (L) 7.20 mOffsets of the base slab provided from the edge of abutment stem 0.40 m both sideOver all Length of Footing (L') 8.00 mHorizontal Nonseismic Forces kN Vertical lever arm mForces due to breaking force 54.329 11.68Horizontal forces due to reisitence of bearing 86.20 8.00Earth pressure (0.5* g * H² * tan²(45° - f/2)*L) at 0.42H 411.90 4.91Vertical Nonseismic Forces kN Horizontal lever arm mLive Load 1302.87 3.35Dead Load from superstructure 2222.40 3.35Dead load of Abutment and Footing 3922.39 3.63Vertical Load of Soil Mass 3287.232 3.70Vertical Load of Approach Slab 103.68 3.58Horizontal seismic forces: kN Vertical lever arm mSuperstructure 266.69 8.18Abutment and footing 470.69 2.76Soil mass 394.47 5.24Approach Slab 12.44 10.38Vertical seismic forces: kN Horizontal lever arm mSuperstructure 133.34 3.35Abutment and footing 235.34 3.63Soil mass 197.23 2.53Approach Slab 6.22 2.65Buyoncy (IRC:6-2000, 216.4 (a)

Upward pressure due to buyoncy = -1453 kN at 3.63 m

Volume of Submerged part of Stem 44.66Volume of Footing 100.64Loads and Moment Calculation

The transverce forces and moments are not calculated since it will not be critical due to high moment of inertia.

ParticularLoad Coefficient IRC:6-2000, 202.3

combination I Dry case, Non-seismic Increment factor for allowable stresses* 1Superstructure dead load 1 2222.40 3.35 7445.05Live load 1 1302.87 3.35 4364.63Abutment 1 3922.39 3.63 14224.30Soil mass/earth pressure 1 3287.232 3.70 411.90 4.91 12162.76 2020.60Approach Slab 1 103.68 3.58 370.66Tractive/Braking force 1 86.20 8.00 689.58Frictional force 1 54.33 11.68 634.56Total 10838.58 552.42 24.59 38567.39 3344.74

combination VI Dry case, Seismic Increment factor for allowable stresses* 1.5Non seismic forces

Superstructure dead load 1 2222.40 3.35 7445.05Live load 0.5 651.44 3.35 2182.31Abutment 1 3922.39 3.63 14224.30Soil mass/earth pressure 1 3287.23 3.70 411.90 4.91 12162.76 2020.60Approach Slab 1 103.68 3.58Tractive/Braking force 0.5 43.10 8.00 344.79

Vertical Lever arm,

(m)

Stabilizing Moment (kN.m)

Overturning Moment

(kN.m)

Vertical force (kN)


Horizontal force

(kN)


Frictional force 0.5 27.16 11.68 317.28Additional seismic forcesSuperstructure 1 133.34 3.350 266.69 8.18 446.70 2181.51Abutment 1 235.34 3.626 470.69 2.76 853.46 1299.85Soil mass 1 197.23 2.525 394.47 5.24 498.02 2067.01Approach Slab 1 6.22 2.650 12.44 10.38 16.49 129.14Total 10753.06 1626.44 37829.08 8360.19

combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* 1Superstructure dead load 1 2222.40 3.35 7445.05Live load 1 1302.87 3.35 4364.63Abutment 1 3922.39 3.63 14224.30Soil mass 1 3287.232 3.70 411.90 4.91 12162.76 2020.60Approach Slab 1 103.68 3.58 370.66Tractive/Braking force 1 86.20 8.00 689.58Frictional force 1 54.33 11.68 634.56Buyoncy 1 -1452.99 3.63 -5269.2Total 9385.58 552.42 33298.20 3344.74

combination VI-a Flooded case, Seismic Increment factor for allowable stresses* 1.5Non seismic forces

Superstructure dead load 1 2222.40 3.35 7445.05Live load 0.5 651.44 3.35 2182.31Abutment 1 3922.39 3.63 14224.30Soil mass 1 3287.23 3.70 411.90 4.91 12162.76 2020.60Approach Slab 1 103.68 3.58 370.66Tractive/Braking force 0.5 43.10 8.00 172.39Frictional force 0.5 27.16 11.68 158.64Buyoncy 1 -1452.99 3.63 -5269.2Additional seismic forcesSuperstructure 1 133.34 3.35 266.69 8.18 2628.21 2181.51Abutment 1 235.34 3.63 470.69 2.76 2153.31 1299.85Soil mass 1 197.23 2.53 394.47 5.24 2565.03 2067.01Approach Slab 1 6.22 2.65 12.44 10.38 145.63 129.14Total 9306.29 1626.44 38608.06 8029.15

Increment factor for allowable stresses* IRC:6-2000, 202.3Check for Stability and Bearing Pressure

Factors of safety (IRC:78-2000, 706.3.4) For Non Seismic For SeismicAgainst overturning 2 1.5Against sliding 1.5 1.25Against deep seated failure 1.25 1.15Frictional coefficient (IRC:78-2000, 706.3.4) (f) = 0.5Maximum Allowable Bearing Pressure (q) = 480 kN/m²Total Length of footing (B) = 8.00 m

B/6 = 1.33


Summary of Loads per meter

Particular/Load cases

Dry (comb. I) 1354.8221 69.052851 4820.92 418.09245Flooded (comb. I-a) 1173.19792 69.052851 4162.28 418.09245

Dry (comb. VI) 1344.1326 203.30551 4728.64 1045.02Flooded (comb VI-a) 1163.28602 203.30551 4826.01 1003.64Check

Dry Flooded

Stability against overturning (MS/MO) 11.53 9.955 2 > than allowableOkStability against sliding (f*V/H) 9.81 8.49 1.5 > than allowableOkEccentricity e1 = B/2 - (MS-MO)/V < B/6 0.75 0.81 1.33 <than allowableOkMax net pressure = (V/B)*(1+6e/B) < q 264.6 235.6 480 < than allowableOkMin net pressure = (V/B)*(1- 6e/B) > 0 74.1 57.7 0 > than allowableOk

Stability against overturning (MS/MO) 4.52 4.808 1.5 > than allowableOkStability against sliding (f*V/H) 3.31 2.86 1.25 > than allowableOkEccentricity e1 = B/2 - (MS-MO)/V < B/6 1.26 0.71 1.33 <than allowableOkMax net pressure = (V/B)*(1+6e/B) < q 326.7 223.3 480 < than allowableOkMin net pressure = (V/B)*(1- 6e/B) > 0 9.3 67.5 0 > than allowableOk

Design of Footing

Calculation of moments and shear forces at the footing due to base pressure

7.40

4.154.65

3.25 2.75

H A B Tσmin σH σT σmax

Case I Case VI Case VI-aEffective moment, M = (MS-MO) 4402.83 3744.2 3683.61 3822.36Critical downward load, V = 1354.82 1173.20 1344.13 1163.29Distance of CG of forces, X = M/V 3.25 3.19 2.74 3.29Eccentricity, e=(B/2)-X 0.75 0.81 1.26 0.71Maximum pressure at Toe, σmax = 264.65 235.58 326.73 223.30Minimum pressure at Heel, σmin = 74.06 57.72 9.31 67.53Upward pressure (shear) at B, σt = 193.82 169.48 208.77 165.41Upward pressure (shear) at A, σh = 157.76 135.83 148.71 135.94Moment at B due to upward pressure 1232.27 1026.8 819.41 1082.78Moment at A due to upward pressure 538.48 442.3 294.56 477.05

At Point B

AllowableCalculated value

Seismic case

Overturning Moment

(kN.m)

Vertical force (kN)

Non Seismic case

Non seismic case

Horizontal force (kN)

Seismic case

Remark

Stabilizing Moment (kN.m)

Moment and shear forces due to base pressure

Non seismic cases Seismic cases

Moment and forces due to Soil and Abutment

Case I-aDescription


Self weight of Toe Slab 112.2Negative force (Lift) due to buyoncy -23.375Seismic Loads 6.73At Point ASelf weight of Heel Slab 132.6Negative force (Lift) due to buyoncy -27.625Downward force due to soil 456.56Seismic Loads 7.96

Case I Case VI Case VI-aMoment and forces due to Soil and AbutmentDownward force at B 112.2 88.825 118.93 95.56Downward force at A 589.16 561.5 597.12 569.49Downward Moment at B 154.28 122.13 163.532 131.391Downward Moment at A 957.39 912.5 970.31 925.42Resultant forces at Toe and Heel

Net Bending moment at heel, A -418.90 -470.2 -675.8 -448.4Net Bending moment at toe, B 1077.99 904.6 655.88 951.39Net Shear Force at heel, A -431.40 -425.7 -14.82 -433.55Net Shear Force at toe, B 81.62 80.7 89.83 69.85Critical Forces and Moments

Critical Moment at Toe Side 1077.99 kN-m per meterCritical Mement at Heel Side -675.75 kN-m per meterCritical Shear Forces at Toe Side 89.83 kN per meterCritical Shear Forces at Heel Side -433.55 kN per meterDesign of Toe Slab

Neutral Axis Factor Xc [m*Scbc/m*Scbc+Sst] = 0.23Lever Arm Z [1-Xc/3] = 0.922Moment of Resistance Factor R [Scbc/2*Z*Xc] = 0.7193Minimum Effective depth requireq deff_min [sqrt(M/R*b] = 1224.2 mmProvided Over all Depth 1700 mmCover provided (Top and Cover) 70 mmSo, effective actual depth deff 1630 mm Ok

Area of Reinforcement required Ast [M/Z*deff*Sst] = 2988.8 mm2

Provided Reinforcement

Per meter TotalTensile Reinforcement (Bottom) 32 120 9 67.00 AF1

25 200 5 41.00 AF3Ast Provided (Bottom) 7238.2 mm² > Ast required OKAst Provided (Top) 2454.4 mm²

Design of Heel Slab

Neutral Axis Factor Xc [m*Scbc/(m*Scbc+Sst)] = 0.23Lever Arm Z [1-Xc/3] = 0.922Moment of Resistance Factor R [Scbc/2*Z*Xc] = 0.7193Minimum Effective depth requireq deff_min [sqrt(M/R*b] = 969.27 mmProvided Over all Depth 1700 mmCover provided (Top and Cover) 70 mmSo, effective actual depth deff 1630 mm Ok

Area of Reinforcement required Ast [M/Z*deff*Sst] = 1873.5 mm2

NosSpacing (mm) c/c providedReinforcement

Compression Reinforcement (Top)

Dia of Bar

Case I-a

Level

Non seismic cases Seismic casesDescription


Provided Reinforcement

Per meter TotalTensile Reinforcement (Bottom) 32 200 5 41.00 AF2

25 300 4 27.00 AF4Ast Provided (Bottom) 4021.2 mm² > Ast required OKAst Provided (Top) 1963.5 mm²

Distribution Bars:

Provide 20 % of Longitudinal Bars as distribution bars of dia 16 mm

490.87 250 12 AF51447.65 130 22 AF6

392.70 250 17 AF5804.25 250 17 AF6

Check For Shear (IRC:21-2000, 304.7.1.3)Toe Heel

Maximum Shear stress developed (V/b*deff) 0.0528 0.255 N/mm²Total longitudinal reinforcement provided (%) 0.570 0.352 %Allowable shear stress without shear reinforcement OK 0.322 0.253 !!!

Additional Shear Reinforcement is required NO YES

Ø 0 @ 0c/c Shear bars bothway AF7

Ø 25 @ 300 mm c/c AF4 Ø 25 @ 200 mm c/c AF3

Ø 16 @ 250 mm c/c AF5 Ø 16 @ 250 mm c/c AF5Ø 16 @ 130 mm c/c AF6

Ø 32 @ 200 mm c/c AF2 Ø 32 @ 120 mm c/c AF1

Ø 16 @ 250 mm c/c AF6 Ø 16 @ 130 mm c/c AF6

Spacing (mm) c/c providedReinforcement

Toe Side

Reinforcement Dia of Bar

Nos

Spacing (mm) c/c providedNos

Level

Level

Summary of reinforcement of Abutment Footing

Compression Reinforcement (Top)

Bottom Face BarHeel Side

Bottom Face Bar

Top Face Bar

Top Face Bar

Area of steel required


Section of Pier

A B C 1.05TPL 285.82

2.500 2.500 2.40

3.00

BPL 283.426.60

HFL 2841.90 8.30

2.80

10.10 MSL 278.22

SBL 277.52

1.80 1.80

FBL 275.727.00 7.00


MSL = Maximum Scour LevelMaterial Properties

Concrete grade (fck) 25 N/mm²Steel grade (fe) 500 N/mm²Allowable stress of steel in tension and shear Sst = 240 N/mm²Allowable stress of steel in direct compression Ssc = 205 N/mm²Allowable compressive stress in concrete in flexure Scbc = 8.33 N/mm²Allowable comp. stress in concrete in direct compression Scc = 6.25 N/mm²Modular ratio (m) m = 10Neutral axis factor k 0.32

j 0.89The resisting moment coefficient R 0.95IRC:21-2000, 303.2.1, Table 9,10Levels

High Flood Level 284 mMaximum Scour level for Pier 278.2 mLevel of Deck Surface 288.3 mThickness of Pier cap (overall Thickness) 2.40 m

2.0 Design of Substructure2.2 Design of Pier Cap & Stem

1.20


Top level of pier cap (TPL) 285.82Top level of Footing (SBL) 277.52 m Thickness of Footing/Cap 1.80 mBottem level of Footing/Cap (FBL) ( 2.5m Below Max Scour Depth) 275.72 mThickness of Bearing 0.18 mHence the total height of Pier H= 10.10 mSoil Data & Seismic Data

Unit weight of backfill soil γ 16 kN/m³Unit weight of concrete ω_conc 24 kN/m³Horizontal seismic coefficient αΗ 0.120Vertical seismic coefficient αν 0.060

DegreeAngle between the wall and earth α 0Angle of internal friction of soil φ 32Angle of friction between soil and wall δ 16

Forces on the Pier at Point A B CDistance from center -2.50 0.00 2.50Total Dead Load from superstructure (kN) 764.61 693.19 764.61

Total Critical Live load including impact (kN) 364.75 417.54 321.84

Moment at the edge of the stem shaftDue to dead load of the cap itself = 207.94 Kn-mDue to dead load from superstructure = 1682.1332 Kn-mDue to live load excluding impact = 802.4478 Kn-mDue to Impact load = 401.2239 Kn-mHence Total Moment 3093.74 Kn-mNeutral Axis Factor Xc [m*Scbc/(m*Scbc+Sst)] = 0.26Lever Arm Z [1-Xc/3] = 0.91Moment of Resistance Factor R [Scbc*Z*Xc] = 1.96Assuming b=1 mMinimum Effective depth requireq deff_min [sqrt(M/R*b] = 1255.32 mmProvided Over all Depth 2400 mmCover provided (Top and Cover) 40 mmDiameter of bar 32 mmSo, effective actual depth deff 2344 mm OkDistance of the bearing center from the face of stem = 1100 mmCap Can be designed as cantileverArea of Reinforcement required Ast [M/Z*deff*Sst] = 6016.258 mm2

Provide 32 mm bars at spacing 150.00 mm c/c, so nos of bars are 20

Provided area of tensile reinforcement = 16085 mm2 OK AP1Reinforcement at the bottom (compression side)Provide 20 mm bars at spacing 220.00 mm c/c, so nos of bars are 14

Provided area of tensile reinforcement = 4398 mm2 AP2Check for Shear

Shear force at the critical sectionDue to dead load of the cap itself = 246.24 kNDue to dead load from superstructure = 1529.212 kNDue to live load excluding impact = 729.498 kNDue to Impact load = 364.749 kN

Design of Pier Cap


Total Shear force V = 2869.699 kNShear Stress developed, tau = V/(B*D) 0.398569306 N/mm²Allowable shear stress for the section (IRC:21-2000, Table 12A) = 1.9 Section ok for shearPercentage of longitudinal steel (tension+compression), pt = 0.291 %Allowable shear stress (IRC:21-2000, Table 12B) = tc = 0.233 < 0.399

Shear reinforcement is requiredShear resisted by the longitudinal steel and concrete section = tc * B * d_eff =

1639942 NShear force to be resisted by shear reinforcement Vus = 1229757 NProviding 4 legs of 16 mm Ø barsThe shear steel area Asv = 804.25 mm²Spacing of bars Sst * Asv *d_eff / Vus = 365 mm c/cCheck for shear at bearings

Check shear at a distance 1.10 m from the face of the stemTotal Depth of beam at the bearing = 1705 mmEffective Depth of beam at the bearing= 1649 mmShear forces:Due to dead load of the cap itself = 115.05 kNDue to dead load from superstructure = 1529.21 kNDue to live load excluding impact = 729.50 kNDue to Impact load = 364.75 kN

Total V = 2738.51 kNShear Stress developed, tau = V/(B*D) 0.54 N/mm²Allowable shear stress for the section (IRC:21-2000, Table 12A) = 1.90 Section ok for shearPercentage of longitudinal steel (tension+compression), pt = 0.414 %Allowable shear stress (IRC:21-2000, Table 12B) = 0.306 N/mm²Shear resisted by the longitudinal steel and concrete section = tc * B * d_eff =

1515200 NShear force to be resisted by shear reinforcement Vus = 1223307 NProviding 4 legs of 16 mm Ø barsThe shear steel area Asv = 804.25 mm²Spacing of bars Sst * Asv *d_eff / Vus = 200 mm c/c AP3Skin reinforcement @ 0.1% of gross sectional area of the beam 7032 mm²For each side = 3516 mm² each sideProviding 16 mm bars 200 mm c/c, hence, 12 nos each sideProvided area at each side = 2413 mm² each side

AP4Check for punching shear

Average depth of section at bearing, i.e. at 1.55 m from the stem face= 2118 mm

Allowable punching pressure, tau_p = ks(0.16*sqrt(fck))Where, ks = the minimum of 1 and 0.5+bc = 1

bc = B/L = 0.75hence, tau_p = 0.8

Total punching stress developed = tau_punch = V/Lo*DWhere Lo = perimeter around the critical plane = 2*(2D+L+B) = 8882.727273 mmHence, tau_punch = 0.000100982 N/mm²

Which is < 0.8 OK


Ø 16 @ 200 mm c/c AP4 Ø 32 @ 150 mm c/c AP1Ø 32 @ 150 mm c/c AP1

Ø 16 @ 200 mm c/c AP3

Ø 16 @ 200 mm c/c AP4Ø 20 @ 220 mm c/c AP2

Ø 20 @ 220 mm c/c AP2

Length of stem column (between the surfaces of the restrains) L = 8300 mmDiameter of column D 2800 mmEffective length of column (IRC:21-2000, 306.2.1) Le = 9960 mm[ effective length factor 1.2 ]

Impact factor

A B C

Total Load (absolute)

(excl. impact)

Total Load (incl. impact)

CG of Load wrt center, m

Distance from center -2.5 0 2.5

Dead Load (kN) 1 764.61 693.19 764.61 2222.40 2222.40 0.000Live load (kN) 1.105 364.75 417.54 321.84 1104.13 1219.81 -0.097Analysis and Design of pier Stem

Dead Load

Dead Load From Superstructure 4444.8 kNDead Load due to pier cap 798.34 kNDead Load of Pier Stem 871.91 kN

6115 kNBreaking 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= 2.48 mAnd this force acts along the bridge at 1.2m above the road level 3.68 m Total weight of the IRC Class A vehicle = 543.29 kNTherefore braking force length = 108.658 kNMoment Due to Breaking Force 399.8614 kN-mEffect of buyoncy [IRC:6-2000, 216.4 (a)]Area of stem at top = 6.158 m²Depth of submerged part of Pier = 6.48 mVolume of submerged part of pier = 39.90 m³Net upward force due to buyoncy = -399.01 kN

Forces on the Pier at Point from superstructure

Summary of reinforcement of Pier Cap

Design of Pier Stem

Total Dead Load


Live Load

Live Load Excluding Impact = 2208.26 kNwhich will act at eccentricity ('CG of Load wrt center) -0.097 mCritical moment due to live load eccentricity -214.525 kN-mFrictional force due to resistance of bearings (temperature effect)Coefficient of thermal expansion of concrete (C) = 0.000009Length of main girders (L) 36950 mmWidth of girder (a) 400 mmAssume width of elastomeric bearing (parallel to span) (b) 300 mmAssume thickness of elastomeric bearing (T) 50 mmDifferential temperature in celcius (dt) 30 degreeNumber of main girders = 3Assume Shear modulus of elastomer (G) 1.2 N/mm² (range 0.6 to 1.2)Elongation of the girder (D) = C*L*dt 9.9765 mmPlan area of the bearing (A) = 120000 mm²Longitudinal force transmitted to the pierF = G*A*D / T = 28.73232 kN per bearingTotal force from all bearings 86.20 kNLateral force due to frictional resistance of bearings, 86.20 kNAnd this force acts along the bridge at 8.30 m from base of stemMoment due to temperature effect 715.43 kN-m(From S. Sir)Force due to water currentExposed height to water current 4.34 mperimeter Area exposed 19.10 mMaximum mean velocity m/sec 1.5

Maximum velocity, Sqrt(2)*V, (IRC:6-2000,213.3), V = 2.12Shape factor for circular end (IRC:6-2000, 213.2), K = 0.66Pressure intensity =0.5KV² (IRC:6-2000, 213.2) = 1.485Hence force due to water current = 18.90 kNMoment due to water current 82.08 kN-mSeismic Forces on

Seismic Forces Due to back fill and Approach Slab are also considered.Horizontal seismic forces:

Forces (kN) Lever Arm (m)Superstructure: 533.38 8.30 4427.03Pier cap 95.80 7.10 680.18Pier stem 104.63 2.95 308.65Total 733.81 5415.86

Vertical seismic forces:

Superstructure: 266.69Pier cap 47.90Pier stem 52.31Total 366.90

Moment (kN-m)


Loads and Moment CalculationVertical

load, PHorizontal load along

traffic(Y-Y)Horizontal load across

traffic (X-X)

Moment along traffic (Y-Y)

Moment across traffic

(X-X)

combination I Dry case, Non-seismic Increment factor for allowable stresses* 1Total Dead load 1 6115.05Live load 1 2208.26 -214.53Tractive/Braking force 1 108.66 108.66 399.86Frictional force 1 86.20 715.43Total 8431.97 194.85 0.00 1115.30 -214.53

combination VI Dry case, Seismic Increment factor for allowable stresses* 1.5Non seismic forcesTotal Dead load 1 6115.05Live load 0.5 1104.13 -107.26Tractive/Braking force 0.5 54.33 54.33 199.93Frictional force 0.5 43.10 357.72Seismic forces 1 366.90 733.81 733.81 5415.86 5415.86Total 7640.41 831.23 733.81 5973.51 5308.60

combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* 1Total Dead load 1 6115.05Live load 1 2208.26 -214.53Tractive/Braking force 1 108.66 108.66 399.86Frictional force 1 86.20 715.43Buyoncy 1 -399.01Water Current 1 18.90 82.08Total 8032.96 194.85 18.90 1115.30 -132.45

combination VI-a Flooded case, Seismic Increment factor for allowable stresses* 1.5Total Dead load 1 6115.05Live load 0.5 1104.13 -107.26Tractive/Braking force 0.5 54.33 54.33Frictional force 0.5 43.10Buyoncy 1 -399.01 715.43Water Current 1 18.90 82.08

Seismic forces 1 366.90 733.81 733.81 5415.86 5415.86

Total 7241.40 831.23 752.71 6131.30 5390.68

Maximum Loads 8431.97 831.23 752.71 6131.30 5390.68

Resultant Critical forces: Vertical Load, P = 8431.97 kNHorizontal Load, H = 1121.39 kNMoment, M = 8164.08 kN.m

Increment factor for allowable stresses* IRC:6-2000, 202.3Sectional area of stem = (Ag) 6157521.6 mm²Let Provide main reinforcement 1.2 % of Sectional areaTotal Area of reinforcement 73890.25921 mm²Let Provide 32 mm dia bars. Provided Number of Bar 92 (AP5)

Spacing between the bars providing in two layers = 87 mm

Cover provided 100 mmGrade of Concrete and Steel same as in Pier CapLet provided diameter of transverse reinforcement 12 mm the diameter up to the line of reinforcement Dc 2560 mmSubstructure Kamala Khola_Bridge Project

So Area of Steel Provided (As) 73990.79018 mm²So Area of Concrete (Ac) 6083530.8 mm²Check for Section capacity of StemEquivalent area of Section Ae = Ac+(1.5m-1)*As= 7119401.9 mm²Equivalent moment of inertia of section Ie = (PI*D^4/64) + (m-1)*As*Dc² / 8

3.5627E+12 mm4

Ze = 2*Ie/D = 2544789202 mm3

Scc = P/Ae = 1.184 N/mm²Scb = M/Ze = 3.208 N/mm²

(Scc/Sacc + Scb/Sacb) = 0.57 <1Satisfied

Check the section for shear

Resultant critical horizontal force: 1121392 NShear stress developed, tau = 0.182 N/mm²Percentage of longitudinal steel (as provided)= 1.202 %Allowable shear stress tc = 0.432 N/mm² Satisfied

Hence, No shear reinforcement required. Provide nominal.Provide 12 mm circular rings @ 120 mm c/c Diameter of ring (mm) 2600

(AP6)

Ø 32 @ 87 mm c/c (AP5)

Ø 32 @ 87 mm c/c (AP5)

Ø 12 @ 120 mm c/c (AP6)

Ø 12 @ 120 mm c/c (AP6) Ø 12 @ 120 mm c/c (AP6)

Ø 12 @ 120 mm c/c (AP6)

Summary of reinforcement of Pier Stem


Section of Pier

A B C 1.05TPL 285.82

2.500 2.500 2.40

3.00

BPL 283.426.60

HFL 2841.90 8.30

2.80

10.10 MSL 278.22

SBL 277.52

1.80 1.80

FBL 275.727.00 7.00


MSL = Maximum Scour LevelMaterial Properties

Concrete grade (fck) 20 N/mm²Steel grade (fe) 500 N/mm²Allowable stress of steel in tension and shear Sst = 240 N/mm²Allowable stress of steel in direct compression Ssc = 205 N/mm²Allowable compressive stress in concrete in flexure Scbc = 6.67 N/mm²Allowable comp. stress in concrete in direct compression Scc = 5 N/mm²Modular ratio (m) m = 10Neutral axis factor k 0.32

j 0.89The resisting moment coefficient R 0.95IRC:21-2000, 303.2.1, Table 9,10Levels

High Flood Level 284 mMaximum Scour level for Pier 278.22 mLevel of Deck Surface 288.3 m

2.0 Design of Substructure2.3 Design of Pier Foundation

1.2


Thickness of Pier cap (overall Thickness) 2.4 mTop level of pier cap (TPL) 285.82Top level of Footing (SBL) 277.52 m Thickness of Footing/Cap 1.8 mBottem level of Footing/Cap (FBL) ( 2m Below Max Scour Depth) 275.72 mThickness of Bearing 0.18 mHence the total height of Pier H= 10.10 mSoil Data & Seismic Data

Unit weight of backfill soil γ 16 kN/m³Unit weight of concrete ω_conc 24 kN/m³Horizontal seismic coefficient αΗ 0.120Vertical seismic coefficient αν 0.060

DegreeAngle between the wall and earth α 0Angle of internal friction of soil φ 32Angle of friction between soil and wall δ 16Length of stem column (between the surfaces of the restrains) L = 8300 mmDiameter of column D 2800 mmEffective length of column (IRC:21-2000, 306.2.1) Le = 9960 mm[ effective length factor 1.2 ]

Impact factor

A B C

Total Load (absolute)

(excl. impact)

Total Load (incl. impact)

CG of Load wrt center, m

Distance from center -2.50 0.00 2.50Dead Load (kN) 1 764.61 693.19 764.61 2222.40 2222.40 0.000Live load (kN) 1.105 364.75 417.54 321.84 1104.13 1219.81 -0.097Forces at bottom of Footing

Dead Load

Dead Load From Superstructure 4445 kNDead Load due to pier cap 798.34 kNDead Load of Pier Stem 871.91 kNDead load of footing 2116.80 kN

8232 kNBreaking 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= 2.48 mAnd this force acts along the bridge at 1.2m above the road level 3.68 m Total weight of the IRC Class A vehicle = 543.29 kNTherefore braking force length = 108.658 kNMoment Due to Breaking Force 399.861 kN-mEffect of buyoncy [IRC:6-2000, 216.4 (a)]Volume of submerged part of pier = 84.00 m³Net upward force due to buyoncy = -840.01 kNLive Load

Live Load Excluding Impact = 2208.26 kNwhich will act at eccentricity ('CG of Load wrt center) -0.097 mCritical moment due to live load eccentricity -214.525 kN-mFrictional force due to resistance of bearings (temperature effect)Coefficient of thermal expansion of concrete (C) = 0.000009Length of main girders (L) 36950 mm

Total Dead Load

Forces on the Pier at Point from superstructure


Width of girder (a) 400 mmAssume width of elastomeric bearing (parallel to span) (b) 300 mmAssume thickness of elastomeric bearing (T) 50 mmDifferential temperature in celcius (dt) 30 degreeNumber of main girders = 3Assume Shear modulus of elastomer (G) 1.2 N/mm² (range 0.6 to 1.2)Elongation of the girder (D) = C*L*dt 9.9765 mmPlan area of the bearing (A) = 120000 mm²Longitudinal force transmitted to the pierF = G*A*D / T = 28.73232 kN per bearingTotal force from all bearings 86.20 kNLateral force due to frictional resistance of bearings, 86.20 kNAnd this force acts along the bridge at 10.10 m from baseMoment due to temperature effect 870.59 kN-m(From S. Sir)Force due to water currentExposed height to water current 5.55 mperimeter Area exposed 24.40 mMaximum mean velocity m/sec 1.5

Maximum velocity, Sqrt(2)*V, (IRC:6-2000,213.3), V = 2.12Shape factor for square end (IRC:6-2000, 213.2), K = 0.66Pressure intensity =0.5KV² (IRC:6-2000, 213.2) = 1.485Hence force due to water current = 24.16 kNMoment due to water current 134.01 kN-mSeismic Forces on

Seismic Forces Due to back fill and Approach Slab are also considered.Horizontal seismic forces:

Forces (kN) Lever Arm (m)Superstructure: 533.38 10.10 5387.10Pier cap 95.80 8.90 852.62Pier stem 104.63 4.75 496.99Footing 254.02 0.90 228.61Total 987.82 6965.33

Vertical seismic forces:

Superstructure: 266.69Pier cap 47.90Pier stem 52.31Footing 127.01Total 493.91

Moment (kN-m)


Loads and Moment CalculationVertical

load, PHorizontal load along

traffic(Y-Y)Horizont

al load across

traffic (X-X)

Moment along traffic (Y-Y)

Moment across traffic

(X-X)

combination I Dry case, Non-seismic Increment factor for allowable stresses* 1Total Dead load 1 8231.85Live load 1 2208.26 -214.53Tractive/Braking force 1 108.66 108.66 399.86Frictional force 1 86.20 870.59Total 10548.77 194.85 0.00 1270.45 -214.53

combination VI Dry case, Seismic Increment factor for allowable stresses* 1.5Non seismic forcesTotal Dead load 1 8231.85Live load 0.5 1104.13 -107.26Tractive/Braking force 0.5 54.33 54.33 199.93Frictional force 0.5 43.10 435.29Seismic forces 1 493.91 987.82 987.82 6965.33 6965.33Total 9884.22 1085.25 987.82 7600.55 6858.07

combination I-a Flooded case, Non-seismic Increment factor for allowable stresses* 1Total Dead load 1 8231.85Live load 1 2208.26 -214.53Tractive/Braking force 1 108.66 108.66 399.86Frictional force 1 86.20 870.59Buyoncy 1 -840.01Water Current 1 24.16 134.01Total 9708.76 194.85 24.16 1270.45 -80.52

combination VI-a Flooded case, Seismic Increment factor for allowable stresses* 1.5Total Dead load 1 8231.85Live load 0.5 1104.13 -107.26Tractive/Braking force 0.5 54.33 54.33Frictional force 0.5 43.10Buyoncy 1 -840.01 870.59Water Current 1 24.16 134.01Seismic forces 1 493.91 987.82 987.82 6965.33 6965.33Total 9044.21 1085.25 1011.98 7835.92 6992.07

Dry, Comb I 10548.77 194.85 0.00 1270.45 -214.53Flooded, Comb I-a 9708.76 194.85 24.16 1270.45 -80.52

Dry, Comb VI 9884.22 1085.25 987.82 7600.55 6858.07Flooded, Comb VI-a 9044.21 1085.25 1011.98 7835.92 6992.07Check for Stability and Bearing Pressure

Factors of safety (IRC:78-2000, 706.3.4) For Non Seismic For SeismicAgainst sliding 1.5 1.25Frictional coefficient (IRC:78-2000, 706.3.4) (f) = 0.5Maximum Allowable Bearing Pressure (q) = 480 kN/m²σ max = (P/A) + (M/Z)

Summary of Load

Non-seismic cases

Seismic cases


σ min = (P/A) - (M/Z) where, σ max = Maximum base pressure (should not exceed the allowable bearing capacity)

σ min = Minimum base pressure (should be > 0, no tension in soil allowed)P = Total vertical load on baseM = Moment at the baseZ = Section modulus of the footing base = bh² / 6A = Area of basef = Frictional coefficient (IRC:78-2000, 706.3.4)

Section modulusAlong the traffic Zyy = 57.17 m³Across the traffic Zxx = 57.17 m³Area of Base A= 49 m2

Stability against sliding: f*(P/H) > factor of safetyH = Horizontal force at the base

237.50 ok 193.06 ok 27.07 ok220.36 ok 175.91 ok 24.91 ok334.67 ok 68.76 ok 4.55 ok321.65 ok 47.50 ok 4.17 ok

211.53 ok 219.03 ok NA196.73 ok 199.55 ok 200.96 ok321.68 ok 81.75 ok 5.00 ok306.89 ok 62.27 ok 4.47 ok

Design of Pier Foundation footing section

Clear cover 35 mm Diameter of main bars: Y-Y : 25 mmX - X : 32 mm

Along Traffic Across Traffic

2.1 2.80 2.1 2.1 2.80 2.10

σ min A B C D A B C Dσ max

σ max = 334.67 σ max = 321.68σ min = 47.50 σ min = 62.27σ B = 195.19 σ B = 455.10σ C = 310.06 σ C = 558.87

combination IIcombination IIIcombination IV

Across Traffic

combination I f*(P/H)Condotion

Along Trafficσ max = σ min =

Condotion σ max = σ min = f*(P/H)combination Icombination IIcombination IIIcombination IV

1752.5 1800 1708


Moment at C:Due to soil pressure 719.86 kN.m 883.65 kN.mDue to self wt. of slab 95.26 kN.m 95.26 kN.mResultant moment = 624.61 kN.m 788.39 kN.m

Shear force at C:Due to soil pressure 676.97 kN 924.58 kNDue to self wt. of slab 90.72 kN 90.72 kNResultant Shear = 586.25 kN 833.86 kNNeutral Axis Factor Xc [m*Scbc/(m*Scbc+Sst)] = 0.217Lever Arm Z [1-Xc/3] = 0.928Moment of Resistance Factor R [Scbc/2*Z*Xc] = 0.672Moment of Resistance, Mr=B*Xc*(Scbc/2) * ZAssuming B = 1 m, Mr = Mr = 672.13 d²

Along Traffic Across TrafficEquating Mr = M, d (min) = 964.00061 mm 1083.04 mmProvided effective d. d_eff = 1752.5 mm ok 1708 mm ok

Area of steel required, Ast=M/(Z*d_eff*Sst)Y - Y (along the traffic) X - X (across the traffic)

1601.055 mm² 2073.53131 mm²


Provide Tensile steel Diameter 25 mm (PF1) 32 mm (PF2)Spacing 200 mm c/c 200 mm c/cNumber 5 nos per meter 5 nos per meterTotal 36 36

Compression bars: Diameter 25 (PF3) 32 mm (PF4)Spacing 300 mm c/c 300 mm c/cNumber 4 nos per meter 4 nos per meter

24 24Check for shearTotal area of longitudinal bars 4417.8647 mm² 7238.22947 mm²Percentage of longitudinal bars 0.2520893 % 0.42378393 %Allowable shear stress 0.234 N/mm² 0.280 N/mm²Shear stress developed 0.335 N/mm² 0.488 N/mm²

Additional shear reinf. Required Additional shear reinf. RequiredShear reinforcementResidual shear stress, Vus = 176355.1 N 477686.119

Diameter 12 12nos/legs 2 per meter 2Spacing 296.74466 mm 300Adopt 300 mm c/c 300 mm c/c (PF5)

Total nos 24 24

Ø 25 @ 300c/c PF3 Ø 25 @ 300c/c PF3Ø 32 @ 300c/c PF4

Ø 12 @ 300c/c Shear bars bothway PF5

Ø 25 @ 200c/c PF1 Ø 32 @ 200c/c PF2

7.00


Label Dia Nos Length Unit Weight (Kg)/m Weight(Kg)

AC1 7070 16 20 7.070 1.578 223.177

1170

935 12 36 4.31 0.888 137.7532x50

AC2

AC3 10 6 16 0.617 59.188

420.1182 840.235

Label Dia Nos LengthUnit

Weight (Kg)/m

Weight(Kg)

450

AS1 6930 32 25 7.830 6.313 1235.837

450

AS25130 32 24 5.58 6.313 845.483

450450

AS3 6930 25 25 7.83 3.853 754.295

450

AS4 5130 25 24 5.58 3.853 516.042

450

7070

AS5 700 700 12 17 16.940 0.888 255.673

70703607.330

2 7214.660

Bar Bending Schedule of Abutment Cap

No of Cap

Total

Shape

Shape

Bar Bending Schedule of Abutment Stem

Total

Total Weight

No of Stem Total Weight

500Pitch 75 mm bothways,2 layers

600



Weight (Kg)/m

Weight(Kg)

250

AB1 4900 32 25 5.15 6.313 812.843

250

AB24550 25 25 4.8 3.853 462.403

7070AB3

250 250 12 9 14.64 0.888 116.978

AB4 16 27 1.82 1.578 77.559

AB510 54 0.65 0.617 21.640

AB6 10 27 0.4 0.617 6.659

AB7 7120 20 1 7.12 2.466 17.559

AB8 7120 16 2 7.12 1.578 22.476

1538.1182 3076.235

Total

No of Back Wall Total Weight

Bar Bending Schedule of Abutment Back Wall

Shape

500 300220

700

100

500

7575

75 75

250



Weight (Kg)/m

Weight(Kg)

AF1 850 4670 850 32 67 6.370 6.313 2694.472

AF2 850 5170 850 32 40 6.870 6.313 1734.907

AF3 850 5170 850 25 40 6.870 3.853 1058.903

AF4 850 4670 850 25 27 6.370 3.853 662.739

AF5 850 7860 850 16 29 9.56 1.578 437.578

AF6 850 7860 850 16 39 9.56 1.578 588.467

100AF7 1560 0 0 1.76 0.000 0.000

100

7177.0672 14354.134

Total

No of Foundation Total Weight

Bar Bending Schedule of Abutment Foundation

Shape



Weight (Kg)/m

Weight(Kg)

AP1 400 6520 400 32 20 7.32 6.313 924.274

AP2 400 40020 14 8.02 2.466 276.899

2800 2210

29204 Legs

AP3 Average H= 16 33 12.72 1.578 662.5221120 2320

AP4 6520 16 12 6.52 1.578 123.489

AP510 12 16 0.61653756 118.3752112

2105.560

1 2105.560


Weight (Kg)/m

Weight(Kg)

AP5 8700 32 92 9.100 6.313 5285.532

400

AP6 D = 2626 12 74 8.450 0.888 555.138

5840.6711 5840.671

Bar Bending Schedule per Pier

Bar Bending Schedule of Pier Stem

No of Stem Total Weight

Shape

Bar Bending Schedule of Pier Cap

No of Cap

Total

Total Weight

Shape

Total

500Pitch 75 mm bothways,2 layers

600



Weight (Kg)/m

Weight(Kg)

PF1 1000 6890 1000 25 36 8.89 3.85336 1233.2293

PF2 1000 6890 1000 32 36 8.89 6.31334 2020.5228

PF3 1000 6890 1000 25 24 8.89 3.85336 822.1528

PF4 1000 6890 1000 32 24 8.89 6.31334 1347.0152

100

PF5 1710 12 576 1.91 0.88781 976.738

1006399.658

1 6399.658No of Foundation Total Weight

Shape

Total

Bar Bending Schedule of Pier Foundation


Substructure_Final_.pdf

Documents

Transcript of Substructure_Final_.pdf