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(1)

Centre to centre of pier 

Centre to centre of pier  20.0020.00mm

RBL

RBL 551.00551.00mm

Bed level of canal

Bed level of canal 570.00570.00mm

Hard rock level;

Hard rock level; 549.50549.50mm

Thickness of pier at top

Thickness of pier at top 1.201.20mm

Sode slope of the pier 

Sode slope of the pier  12V:1H12V:1H

Base width

Base width 2.532.53mm

Width of the trough

Width of the trough 5.555.55mm

Depth of flow of water 

Depth of flow of water  4.804.80m (including surge)m (including surge) Thickness of bed slab of trough

Thickness of bed slab of trough 0.750.75mm

Ground level

Ground level 560.00560.00mm

Top of deck slab of catwalk

Top of deck slab of catwalk 575.65575.65mm

Thickness of bearing

Thickness of bearing 0.500.50mm

Thickness of bed block/pier cap

Thickness of bed block/pier cap 0.750.75mm

 Assume thickness of well cap=

 Assume thickness of well cap= 1.251.25mm

Size of the base

Size of the base 2.2.5353mm X 5X 5.0.00m0m

Bottom of deck slab

Bottom of deck slab 569.25569.25mm

Top of bed block level

Top of bed block level 568.75568.75mm

Bottom of bed block

Bottom of bed block 568.00568.00mm

Height of pier 

Height of pier  8.008.00mm

Horizontal seismic coefficient

Horizontal seismic coefficient 0.080.08gg

Deepest bed level

Deepest bed level 549.50549.50mm

T

Thhiicckknneessssooffsstteeiinniinngg 00..7700 mm P

Piieerrlleennggtthhbbeelloowwccoorrbbeell 55 mm DESIGN OF WELL CAP

DESIGN OF WELL CAP

1 1

(2)

2. TENTATIVE SECTION OF THE PIER 575.65m V1=343.93t V1=343.93t on each bearing H=37.22T 1.20m 1 1 12 12 V2=191.446t 2.53m 560.00m 551.00m V1= D h .50m

(3)

5.00m Myy 2.53m Mxx

+VE

+VE

+VE

3

(4)

3. EVALUATION OF FORCES:

a)Dead load of super structure

R.L.of section under consideration 560.00 m

SL.NO. DESCRIPTION OF LOAD NO. V(t) transition

I TROUGH PORTION

1 Weight of side beams 2 20.00 X 1.00 X 4.02 X 2.40 385.92

2 Weight of fillets 2 20.00 X 1.50 X 0.78 X 2.40 111.60

3 Weight of chamfers 2 20.00 X 0.65 X 1.21 X 2.40 75.63

4 weight of bed slab 1 20.00 X 2.50 X 0.45 X 2.40 54.00

5 Weight of bottom stiffener 6 0.50 X 4.00 X 0.65 X 2.40 18.72

6 Weight of top stiffener 6 0.50 X 5.50 X 0.75 X 2.40 29.70

7 Weight of top wedge/ext beam 6 20.00 X 0.40 X 0.35 X 2.40 40.32 8 Weight of side stiffener 6 0.70 X 2.19 X 0.50 X 2.40 11.06 9 Weight of cat walk beam 1 20.00 X 0.30 X 0.75 X 2.40 10.80 10 Weight of cat walk slab 1 20.00 X 0.90 X 0.20 X 2.40 8.64

11 Weight of water 1 20.00 X 5.50 X 4.80 X 1.00 528.00

12 weight of wearing coat 1 20.00 X 1.65 X 0.08 X 2.40 5.94

13 Weight of railing 6 20.00 X 0.25 X 0.25 X 0.79 5.89

14 Live Load 1 20.00 X 1.20 X 1.00 X 1.00 24.00

15 Add for unforseen loads 5% 65.51

TOTAL 1375.72 1500 125.25721

II PIER CAP

1 piercap 1 1.80 X 8.00 X 0.75 X 2.40 25.92 15.967145

III PIER

1 weight of corbel portion 1 1.18 X 5.15 X 2.00 X 2.40 29.05 93.482906

2 Weight of pier 1 1.87 X 5.00 X 7.25 X 2.40 162.40 3500

217.37 432

III FOUNDATION

1 Well cap 1 3.14 X 8.41 X 1.25 X 2.40 79.26 216.22

79.26

Total with well cap 1672.35

(5)

Earthquake forces

H= 15.65

DESCRIPTION OF LOAD NO.

seismic

factor He Ve L1 L2 M1 M2

m m t m m t-m t-m

I TROUGH PORTION

1 Weight of side beams 1 11.65 0.09 34.47 17.24 11.65 2.50 401.62 43.09

2 Weight of fillets 2 16.20 0.12 13.86 6.93 16.20 2.50 224.57 17.33

3 Weight of chamfers 2 12.75 0.10 7.39 3.70 12.75 2.50 94.27 9.24

4 weight of bed slab 1 16.53 0.13 6.84 3.42 16.53 2.50 113.07 8.55

5 Weight of bottom stiffener 6 15.98 0.12 2.29 1.15 15.98 2.50 36.63 2.87

6 Weight of top stiffener 6 15.40 0.12 3.51 1.75 15.40 2.50 54.01 4.38

7 Weight of top wedge/ext beam 2 15.28 0.12 4.72 2.36 15.28 2.50 72.14 5.90

8 Weight of side stiffener 2 14.86 0.11 1.26 0.63 14.86 2.50 18.71 1.57

9 Weight of cat walk beam 1 15.43 0.12 1.28 0.64 15.43 2.40 19.70 1.53

10 Weight of cat walk slab 1 15.55 0.12 1.03 0.52 15.55 1.60 16.02 0.82

11 weight of wearing coat 1 15.55 0.12 0.71 0.35 15.55 2.50 11.01 0.89

12 Weight of railing 6 16.25 0.12 0.73 0.37 16.25 1.60 11.92 0.59

TOTAL 78.10 39.05 1073.68 96.77

II PIER

1 piercap 1 16.03 0.12 3.18 1.59 16.03 1.6 51.04 2.55

2 weight of corbel portion 1 14.65 0.11 3.26 1.63 14.65 2.50 47.80 4.08

3 Weight of pier 1 10.03 0.08 12.48 6.24 10.03 2.50 125.15 15.60 0.00 18.93 9.47 223.99 22.23 III FOUNDATION 1 Wellcap 1 0.50 0.00 0.30 0.15 0.50 2.50 0.15 0.38 0.30 0.15 0.1519407 0.38 total 97.339 48.670 1297.818 119.383 SL.NO. h    H 1.5ah 5

(6)

Y1= 2.45 ey= -1.186265 m

X1= 26.67 ex= -24.16586 m

HYDRODYNAMIC FORCES (trough)

He

Horizontal hydrodynamic force=He=0.726pey Moment about C.G=Me=0.299p e y 

y[m] 4.80

h[m] 12.40

i Dueto upstream water 

a= 21.337o Cm= 0.570 Cs= 0.403 pe= 0.400 t/sq.m He= 27.88 t Me= 100% 55.12 t-m

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(7)

Dynamic force in the longitudinal direction in the trough

Discharge in the trough(max) 47.25 cumec

Cross sectional area of flow= 26.640 sq.m

Perimeter of the flow of water in the trough 15.150 m

Kinematic viscocity= 1.14E-06 sq.m/sec

Flowvelocity 1.77 m/s

ReynoldsNo. 7500

DragCoeffcient 0.123

Dragforce 37.22 t

Hydraulicmeandepth 1.758 m

Shear force due to water/m length= 1.758 kg

Totalforce 0.533 t

R.L. of application of force 578.050 m

Height above the bed block= 10.050m

Increase in reaction due to drag force= 37.221 t

Force due to sliding friction:

Reaction sliding end when the loads are so placed as to produce maximum reaction on the other end

L.Lreaction= 24.00 t

Impactfactor 25.00%

Impactload 6.00 t

Impactload 6.00 t

Deadloadreaction 41.27 t

Load due to water in flow direction force 37.22 t 84.49 t

Friction in sliding (Coeff of friction= 0.25 21.12 t

R.L. of point of application of force 568.00 m

(8)

Wind force

The inensity of wind pressure depends on the height of structure exposed to the wind. Two cases are dealt for computing wind force

(a). When level of water in the river is at HFL (b). When there is minimum water level

 Average height of pier above GL= 8.00 m

 Area of exposed structure 148.27 sq.m

HeightofpieraboveGL= 10.00 m

Intensity of wind pressure 121.77 kg/sq.m

 Area of exposed structure 148.27 sq.m

 Add for catwalk area 30.00 sq.m

Totalarea= 178.27 sq.m

Total wind force on the structure= 21.71 t

l1 6.40 m

l2 3.60 m

y= 5.713 m

(9)

MOMENT OF INERTIA OF PIER AT BASE:

 Area of the base

B= 2.533m

L= 5.000m

 A = B x L = =12.67 m2

M.I. Of the foundation:

=6.77 m4

=26.39 m4

Coeff. Friction at the bearings= 0.90 12 3  LB  I  x  x = -12 3  BL  I  y- y =

L B X X Y Y 1 4 3 2 9

(10)

SL.NO LOAD HX Hy DIRECT STRESS X BENDING STRESS (fx) BENDING STRESS (fy) t t t t/sq.m m t/sq.m t/sq.m

1 DEADLOAD 1593.09 125.77 negligible

-do-dryCONDITION 1065.09 84.09

5 FORCEDUETOSLIDINGFRICTION 21.12 8.00 31.60 0.00

6 WINDFORCE 21.71 16.21 0.00 33.34

13 EARTQUAKE FORCES -48.67 97.34 97.34 -3.84 as above 0.00 112.77

222.56

14 HYDRODYNAMICFORCES 27.88 10.31 5.22

DETAILS

(11)

CASE V Hx Hy F/A Sf x Sf y f1 f2 f3

t t t t/sq.m t/sq.m t/sq.m t/sq.m t/sq.m t/sq.m

1 STATIC & DRY CONDITION 1065.091 21.707 84.086 0.000 -33.341 50.75 117.43 117.43

2 1593.091 21.707 21.123 125.770 0.000 -33.341 124.03 190.71 127.51

dirction of eq. along flow

4 CASE(1)+E.Q(NO. W IND FORCE) 1016.421 97.339 118.462 80.244 0.000 46.084 302.81 302.81 -142.32

5 CASE(2)+E.Q(NO. WIND LOAD) 1544.421 125.224 118.462 121.928 10.307 51.306 386.39 386.39 -142.54

dirction of eq along the bridge

6 CASE(1)+E.Q(NO. WIND FORCE) 1016.421 97.339 118.462 80.244 0.000 46.084 -32.52 193.01 226.35

7 CASE(2)+E.Q(NO. WIND LOAD) 1544.421 125.224 118.462 121.928 10.307 51.306 51.07 276.60 276.60 dirction of eq across thebridge

Min. stress -32.521 117.427 -142.539 Max. Stress 386.395 386.395 276.597

max Tension= -142.539 t/sq.m Max . Compress ion= 386.395 t/sq.m STATIC & WHEN THERE IS WATER (

IN TROUGH) CONDITION

(12)

Design of well cap:

Diameter of well(internal) 4.40 m

Externaldia 5.80 m

Effective dia= Min of L+d or L+t 5.10 m

depthassumed 1.25 m

Intensity of loading= 95.985 t/sq.m

 Assuming well cap to be partially fixed moment,

Moment at mid span= 78.018 t-m

Grade of concrete M 20

Permissible stress in steel 1900.00 kg/sq.cm

Permissiblebond stress= 8.00 kg/sq.cm

Permissible tensile strength in concrete= 20 kg/sq.cm Whether with Earthquake considered(Y/N)

Permissible compressive strength of concrete= 7 N/mm2

m= 13.3333

k= 0.3294

 j= 0.8902

Q= 10.2634 bd2

Depthofwellcap= 87.19 cm

Steel required at mid span & bottom of well cap (+ve moment)

Dia of the bar 25 mm

 Area 4.91 sq.cm Overalldepth= 102.19 cm Say 125.00 cm Effectivedepth= 117.50 cm  Area of steel= 39.26 sq.cm Spacing= 12.50 cm c/c Say 125 mm c/c b Q  Mx105

(13)

Steel required at bottom in lateral direction(across width of pier)

Moment= 39.009 t-m

Depthofwellcap= 25.32 cm

Dia of the bar 20 mm

 Area 3.142 sq.cm Overalldepth= 39.32 cm Say 125 cm Effectivedepth= 117.5 cm  Area of steel= 19.629 sq.cm Spacing= 16.0 cmc/c Say 150 mm c/c

Distance from face to of the support upto which radial reinforcement is to be provided

Location of zero radial moment from centre= 1.47 m

Therefore distance from support= 1.43 m

Addforthickness= 2.13 m

This will be greater of the following

1. Ld=fs/4tbd= 148.44 cm 2. Point of inflection+d 220.75 cm 3. Point of inflection+12f 132.00 cm Maximum= 220.75 cm Say 220 cm 3  R 13

(14)

Area of reinforcement /width for -ve B.M. Mr at edges(radial rods)

Moment= 78.018 t-m

Depth of well cap=

Dia of the bar 25 mm

 Area 4.909 sq.cm Overalldepth= 125.00 cm Effectivedepth= 120.00 cm  Area of steel= 38.439 sq.cm Spacing= 12.770 cmc/c Say 125 mm c/c

Column dowel reinforcement:

Tensile stress -142.54 t/sq.m

Tensileforce= -57.64 t

 Area of steel= 30.34 sq.cm

Dia of the bar 25.00 mm

 Area 4.91 sq.cm Spacing= 16.18 cm c/c Say 150.00 mm c/c 2 16 2 WR

(15)

Distribution steel at top

Dia of the bar 20 mm

ast= 3.14 sq.cm

 Area of steel= @.12% of Ac 15 sq.cm

Spacing 20.94 cmc/c

Say 200 cm c/c

At the edge of slab, the mesh bars are free and are not capable of taking full tension. Therefore 20mm dia at 200 c/c circumferentail steel is provided for a length of up to 1.30m from the inner edge In the cntral region provide 20mm dia @ 200 c/c both ways

Check for shear

shear force= 607.91 kN

Shear stress 0.52 N/mm2

% of steel= 3.14 %

correctionfactor= 1.30 k

Permissible shear stress= 0.44 N/mm2

Permissible Shear stress kt 0.57 N/mm2

Balanceshear - N/mm2

(16)

-50.00 0.00 50.00 100.00 150.00 200.00 250.00 0 5.00    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

CASE-6 (STRESS ES AT POINT1 & 2)

0.00 50.00 100.00 150.00 200.00 250.00 300.00 0 5.00    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m)

PIER DESIGN -STRESS AT FOUNDATION CASE-7 (STRESS ES AT POINT1 & 2)

0.00 50.00 100.00 150.00 200.00 250.00 300.00 350.00 400.00 450.00 0 5.00    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m)

PIER DESIGN -STRESS AT FOUNDATION CASE-5. (STRESS ES AT POINT1 & 2)

0.00 20.00 40.00 60.00 80.00 100.00 120.00 140.00 0 5.00    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

(17)

0.00 50.00 100.00 150.00 200.00 250.00 300.00 350.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

CASE-3(@1 & 3) 0.00 50.00 100.00 150.00 200.00 250.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

CASE-2(@1 & 2) 122.00 123.00 124.00 125.00 126.00 127.00 128.00 0 5.00    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

CASE-2 (STRESS ES AT POINT1 & 3)

0.00 20.00 40.00 60.00 80.00 100.00 120.00 140.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q .   m    ) BASE WIDTH(m)

PIER DESIGN -STRESS AT FOUNDATION CASE-1(POINT@1 & 3)

(18)

-200.00 -100.00 0.00 100.00 200.00 300.00 400.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

CASE-3(POINT@1 & 3) -200.00 -100.00 0.00 100.00 200.00 300.00 400.00 500.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m)

PIER DESIGN -STRESS AT FOUNDATION CASE-4(POINT@1 & 3) -50.00 0.00 50.00 100.00 150.00 200.00 250.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m)

PIER DESIGN -STRESS AT FOUNDATION CASE-5(POINT@1 & 3) 0.00 50.00 100.00 150.00 200.00 250.00 300.00 0 2.53    S    T    R    E    S    S    (    t    /  s  q  .   m    ) BASE WIDTH(m) PIER DESIGN -STRESS AT FOUNDATION

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