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Psgirder

The document describes a bridge project with a beam length of 40.6 meters spanning 40 meters. It provides details on the materials used, including concrete strengths of 500 kg/cm^2 and 350 kg/cm^2, rebar grades, and prestressing steel specifications. It also includes a cross section diagram of the girder.

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0% found this document useful (0 votes)
42 views6 pages

Psgirder

The document describes a bridge project with a beam length of 40.6 meters spanning 40 meters. It provides details on the materials used, including concrete strengths of 500 kg/cm^2 and 350 kg/cm^2, rebar grades, and prestressing steel specifications. It also includes a cross section diagram of the girder.

Uploaded by

georgewennyi
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 6

Project name :

ref. number : Stressing at f ci'= 80.0 % f c'


Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

I. GENERAL 40.60 m

x
210.0 cm

40.00 m

Beam sectional shape : I SEGMENTAL


Composite / Non Composite Komposit Inner Diafragm,
Beam length : Lb = 40.600 m number: 5
Span length : L = 40.000 m thickness: 20.0 cm
Clear span : Ln = 39.700 m Top slab thickness: 20.0 cm
Curvature : r = 0.000 m Deck plate thickness: 7.0 cm
Girder space : s = 1.850 m
NOTE1
Segemental joint posistion, x = 17.000 m
NOTE1: ASSOCIATES VALUE NOT VALID IF MONOLITH
II. MATERIALS
2.1. Concrete
Beam Slab
2 2
* Concrete grade : cube strength, f cu : 500 [kg/cm ] 350 [kg/cm ]
2 2
cylinder strength, f c' : 432 [kg/cm ] 291 [kg/cm ]
* Modulus of elasticity Ec = 3.64E+05 [kg/cm2] 2.99E+05 [kg/cm2]
* Unit weight gc= 2500 [kg/m3] 2400 [kg/m3]
* Allowable stresses :
- At transfer condition
concrete strength at stressing : 80.00 % f c'.
2
f ci' = 345.3 [kg/cm ] 233.0 [kg/cm2]
Compressive stress : 0.55 f ci'
2 2
= 189.9 [kg/cm ] 128.2 [kg/cm ]
Tensile stress : -0.80 SQR(f ci')
2 2
= -14.9 [kg/cm ] -12.2 [kg/cm ]
- At service condition
2
f c' = 431.6 [kg/cm ] 291.3 [kg/cm2]
Compressive stress : 0.40 f c'
= 172.6 [kg/cm2] 116.5 [kg/cm2]
Tensile stress : -1.60 SQR(f c')
= -33.2 [kg/cm2] -27.3 [kg/cm2]

2.2. Steel rebar


* Diameter < 13 mm, BjTp - 24
fy = 2400 [kg/cm2]
* Diameter >= 13 mm, BjTd - 40
fy = 4000 [kg/cm2]
* Modulus of elasticity, Es = 2.1E+06 [kg/cm2]

2.3. Prestressing steel


* Uncoated stress-relieved seven wire strand.
* Grade-270 - ASTM A416.
* Nominal diameter : 12.70 mm.
* Nominal area : 98.71 mm2.
2
* Modulus of elastisity : 1.97E+06 kg/cm
* Breaking Load : 18.700 ton.
* Low-Relaxation.

III. REFERENCE and CODE


* Bridge Management System (BMS Indonesia-Australia)

IV. CROSS SECTION of GIRDER


bef = 154.8

20.0
60.0 60.0
7.0 7.0
80.0 13.0 80.0 13.0

12.0 12.0

h= 210.0 128.0 128.0

20.0 20.0

25.0 25.0

25.0 25.0
70.0 70.0

Precast Komposit
bef : 154.8 [cm]
h : 210.0 [cm] 230.0 [cm]

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 1 OF 6
Project name :
ref. number : Stressing at f ci'= 80.0 % f c'
Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

2 2
Ac : 7495.0 [cm ] 10590.6 [cm ]
Ac : Y top : 109.2 [cm] 94.4 [cm]
Ya : Y bottom : 100.8 [cm] 135.6 [cm]
4 4
Yb : Ix : 41087032.6 [cm ] 72317460.3 [cm ]
3 3
W top composite : - [cm ] 766426.3 [cm ]
3
W top precast : 376260.5 [cm ] 972574.8 [cm3]
W bottom : 407602.8 [cm3] 533144.4 [cm3]

V. LOADS,and related MOMENTS at the middle of span (and at x for segemental beam)

5.1. Selfweight of beam


qsw = Ac x gc
= 1.874 ton/m.
M sw = (qbs x L^2)/8
= 374.750 ton-m. at x= 366.318 tm

5.2. Self weight of topping slab


* Thick's, t= 0.200 m.
* qts = s.t.gc
= 0.888 ton/m.
* M ts = (qts x L^2)/8
= 177.600 ton-m. at x= 173.604 tm

5.3. Superimposed dead load (SDL)


a. Deck slab
* Thick's t= 0.070 m.
* qds = s.t.gc
= 0.210 ton/m.
* M ds = (qds x L^2)/8
= 42.000 ton-m. at x= 41.055 tm
b. Diafragm
* Pd = 1.307 ton const.for formula = 0.625
* Md = 32.670 ton m at x= 31.935 tm inner diaf. = 5
c. Trotoar + Railing
* qt = [total]
= 0.000 ton/m.
* M t = (qt x L^2)/8
= 0.000 ton-m. at x= 0.000 tm
d. Trotoar Live load
* qtl = [total]
= 0.000 ton/m.
* M tl = (qtl x L^2)/8
= 0.000 ton-m. at x= 0.000 tm
e. Aspalt
* Thickness, t = 0.075 m.
* U weight, gas = 2.300 ton/m3.
qas = s x t x gas
= 0.319 ton/m.
M as = (qas x L^2)/8
= 63.825 ton-m. at x= 62.389 tm

5.4. Live load


* For calculation of strength of girders, should use "D" Load.
* Line load, P = 12.000 ton/m per way.
or Pg = P/2.75 ton.
= 8.073 ton per girder.
* Impact load: Impact need only considered for
line load "Pg".
DLA = 0.400
K= 1.400
* Uniformly distributed load:
- L < 30.0 m, pr = 2.2 ton/m/way.
- L > 30.0 m, pr = 2.2x(0.5+15/L) ton/m/way.

For L = 40.000 m
pr = 1.925 ton/m/way.
or pr = s . p/2.75 ton/m per girder.
= 1.295 ton/m per girder.
* Loading reduction factor D a= 1.000
* For moment calculation
p = a . pr
= 1.295 ton/m per balok.
P = a . K . Pg
= 11.302 ton per balok.
M LL = p.L^2/8 + P.L/4
= 372.018 ton-m. at x= 363.648 tm
* For shear calculation
p = a . pr
= 1.295 ton/m per girder.
P = a . K . Pg
= 11.302 ton per girder.

SERVICE (ton-m) ULTIMATE (ton-m)


5.5. Resume of loads and related moments at x at x
* Moment due to beam selfw't M sw = 374.75 366.32 449.70 439.58
* Moment due to slab selfw't, M ts = 177.60 173.60 213.12 208.32
* Moment due to deck plate, M ds = 42.00 41.06 84.00 82.11
* Moment due to diafragm, Md = 32.67 31.93 65.34 63.87
* Moment due to trotoal +railing, Mt = 0.00 0.00 0.00 0.00
* Moment due to trotoar live load, M tl = 0.00 0.00 0.00 0.00
* Momen beban asphalt, M as = 63.83 62.39 127.65 124.78

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 2 OF 6
Project name :
ref. number : Stressing at f ci'= 80.0 % f c'
Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

* Moment due to live load, M LL = 372.02 363.65 744.04 727.30


-------------------- ------------------ ----------------- ---------------
Moment total, M and M ult, respectively = 1062.86 1038.95 1683.85 1645.96

VI. ANALYSIS
6.1. Prestressing force

2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11

cgc Y1 [cm] : 100.802 11.803 100.802


cgs Yp [cm] : 100.802 100.802
Concrete cover, = 11.803 cm.
Eccentricity, e= 88.998 cm. ep = 0.000

Check at two conditions:


6.1.1. Initial condition at the middle of span

Top fiber :
s t = Pi/Ac - Pi.e/Wt + M sw/Wt => -14.9
Pi <= 1110.098 ton. ..... (1)
Bottom fiber:
s b = Pi/Ac + Pi.e/Wb - M sw/Wb <= 189.9
Pi <= 801.226 ton. ..... (2)

From (1) dan (2) obtained Pi <= 801.226 ton. ..... (3)

6.1.2. Final condition at the middle of span


Top fiber :
s t = Pe/Ac - (Pe.e-M sw)/Wtp + (M LL+M SDL)/Wtc => 172.6
Pe => 376.456 ton. ..... (4)
Bottom fiber:
s b = Pe/Acp + (Pe.e-M sw)/Wbp - (M LL+M SDL)/Wbc => -33.2
Pe => 575.210 ton. ..... (5)

From (4) and (5) obtained Pe => 575.210 ton. ..... (6)

Long term losses are assumed = 15 %.


From (3) and (6) shown that stressing shall be single stage.

Number of required strands approximatly = 51 strands


Number of provided strands = 61 strands
Type of tendons choosed 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11
( SINGLE -LIVE END)
6.2. Prestress losses
JACKING FORCE = 75.8 % UTS.
then, PJF = 864.080 ton.

6.2.1. Short term losses


6.2.1.1. Friction at anchor and jack
Loss for VSL system, dfa = 3 %.
Force at anchor, Pa = (1-dfa) . PJF
= 838.158 ton.
6.2.1.2. Firction due to curvature and wooble effect
Px = Pa.e^(-mu(alpha+beta.lx))
where
Px : prestress force at x from anchor.
mu : Coefficient for friction between duct and strand,
used mu = 0.200
alpha : number of curvature angle until x.
beta : coefficient for wobble effect,
used beta = 0.0114
Point- 2 (middle of span)
L2 = 20.300 m.
alpha = 0.087 rad.
P2 = 786.388 ton.
Titik-
3 (beam end)
L3 = 40.600 m.
alpha = 0.175 rad.
P3 = 737.816 ton.

6.2.1.3. Draw-in
draw-in influence distance at cable,
xd = SQR(dr . Ep . Ap / m)
where :
dr = draw-in occurred of used system,
at VSL system, draw-in is = 0.006 m.
Ep = Elasticity of prestressing steel
2
For used strand, Ep = 1.95E+06 kg/cm .
Ap = total area of used strands,
namely = 60.213 cm2.
m = inclination of force from diagram,
= 2(Pa - P2)/Lb = 2550.2 kg/m.
Then, obtained
xd = 16.621 m.
Hence,
P1 = 753.385 ton.
P2 = 786.388 ton.
P3 = 737.816 ton.

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 3 OF 6
Project name :
ref. number : Stressing at f ci'= 80.0 % f c'
Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

Pave = 765.289 ton.


2
T2pi = 12709.7 kg/cm .
6.2.1.4. Elastic shortening of concrete
dTpe = n.Tst/2
i = (I/Ac)^0.5
= 74.040 cm.
Ke = (Ap/Ac) (1+e^2/i^2)
= 0.020
n= Ep/Ec
= 5.419
dTpe' = n.Ke.Tpi/(1+n.Ke)
= 1222.6 kg/cm2.
Due to selfweight of beam;
M= 374.750 ton-m.
dTpe = ((dTpe')-(n.M.y/I))/2
= 391.4 kg/cm2.
P2i = P2 - Ap.(dTpe)
= 762.823 ton.
6.2.2. Long term losses
6.2.2.1. Shrinkage

dTsh = Ep.Eb.ke.kh.kp
Theoritical thickness of beam = 306 mm.
From Australian Standard 1481-1978 determined;
2
Ep = 1.97E+06 kg/cm .
Eb = 4.00E-04 for humidity = 70.0 %.
ke = 0.649
kh = 0.910 for stressing after = 14.0 days
kp = 100/(100+20.r) where r = percentage of rebar.
rebar chosen, diameter
D = 13 mm.
number = 22 nos
hence, r = 0.39 %.
= 0.928

2
dTsh = 431.7 kg/cm .

6.2.2.2. Creep

dTc = kc.kd.ke.kh.Ep.Tci/Ec
where;
kc = 1.10 for humidity = 70.0 %.
kd = 1.200 for stressing after = 14.0 days
ke = 0.649
kh = 0.910
2
Ep = 1.97E+06 kg/cm .
2
Ec = 3.64E+05 kg/cm .
2
Tci = 147.1 kg/cm .

2
dTc = 621.1 kg/cm .

6.2.2.3. Relaxation of strand

dTr = Fr.R.Tpi.[1-2.(dTsh+dTc)/Tpi]
Pi = 762.823 ton.
66.9 % UTS --> Fr = 1.844
For low-relaxation strand, pure relaxation
R= 2.5 %.
2
Tpi = 12668.7 kg/cm .
2
dTsh+dTc = 1052.8 kg/cm .

2
dTr = 486.9 kg/cm .

6.2.3. Resume of prestress force in beam

* After short term losses;


P1 = 729.820 ton.
P2 = 762.823 ton. Pi max. = 801.226 ton.
P3 = 714.251 ton.

* After long term, losses;


Total long term losses;
dTt = dTsh + dTc + dTr
= 1539.6 kg/cm2.
P1 = 637.114 ton.
P2 = 670.118 ton. Pe required = 575.210 ton.
P3 = 621.545 ton.
6.2.4. Stresses at critical section
1. AT THE MIDDLE OF SPAN
* Immediately after transfer;
Stresses CHECK Allowable
Top fiber : 20.9 kg/cm2. OK ! -14.865
Bottom fiber : 176.4 kg/cm2. OK ! 189.906

* At service condition;

Slab top fiber : 56.9 kg/cm2. OK ! 116.510


Beam top fiber : 142.4 kg/cm2. OK ! 172.642
Bottom fiber : 0.1 kg/cm2. OK ! -33.240

2. AT SUPPORT

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 4 OF 6
Project name :
ref. number : Stressing at f ci'= 80.0 % f c'
Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

* Immediately after transfer;

Top fiber : 111.8 kg/cm2. OK ! -14.865


Bottom fiber : 111.8 kg/cm2. OK ! 189.906

* At service condition;

2
Top fiber : 79.1 kg/cm . OK ! 172.642
Bottom fiber : 79.1 kg/cm2. OK ! -33.240

6.2.5. Elongation of cables due to stressing

* Force diagram at stressing;


PJF = 864.080 ton. Ljack = 0.750 m.
P1 = 838.158 ton.
P2 = 786.388 ton. L2 = 20.300 m.
P3 = 737.816 ton. L3 = 20.300 m.

* Elongation of cable is obtained by formula:


dLi = (Pi x Li) / (Ep x Ap)

Hence, dL1 = 5.5 mm.


dL2 = 139.0 mm.
dL3 = 130.4 mm.

Total elonagtion of cable is = 274.9 mm.

6.3.Ulimate capacity calculation

Ultimate moment = 1683.85 ton-m.

2
Apt = 60.21 cm .
2
fp = 19000.00 kg/cm .
2
f e min = 10580.99 kg/cm .
2
0.5*f p = 9500.00 kg/cm .
fe min > 0.5*fp OK!

s pu = f p*(1-k1*k2/j)
k1 = 0.400
k2 = 1/(bef*dp*f c')*{Apt*fp + (Ast - Asc)/f sy}
= 0.114
0.85 - 0.007*(f c'-28) = 0.843
j = 0.843
s = 17968.273 kg/cm2.
T = 1081.925 ton.

C = T ====> T = j * kud * bef * f c'

a = j * kud = 24.06 cm.


a,max = 20.00 cm.

M n = T * (dp - a/2) = 2230.560 ton-m. Strength reduction factor, f = 0.900


M cr = Zb*(f cf' + P/Ag) +P*e = 1110.956 ton-m.
M uk = fM n = 2007.504 ton-m.
Muk > Mu and Muk > 1.2*Mcr ===> OK !!! (Rebar not considered yet)

6.4. Shear Calculation


* At section with distance d from support, d = 2.18 m.

bv = 11.10 cm.
0.8h = 168.00 cm.
bw = 20.00 cm

Shear Moment
[ton] [ton-m]

- Due to selfweight of beam : 33.949 78.535


- Due to selfweight of slab : 16.089 37.219
- Due to SDL : 10.240 25.742
- Due to live load :
- Load P : 5.651 12.330
- Load p : 23.463 54.278

- Factor for dead load = 1.200


- Factor for SDL = 2.000
- Factor for live load = 2.000

- ULTIMATE LOAD : 138.753 323.605

2
vu = Vu/(bv*d ) = 57.29 kg/cm .

* Maximum concrete shear strength

Vc = 0.2 * f c' * bv * d + Pv
Pv = dy/dx * Pe = 50516.01 kg.
Vc = 251540.65 kg.

* Flexural shear cracking strength

Vc = b1 * b2 * b3* bv * d * {(Ast+Apt)*f c'/(bv*d)}^(1/3) + V0 +Pv


b1 = 1.10
b2 = 1.00
b3 = 1.00

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 5 OF 6
Project name :
ref. number : Stressing at f ci'= 80.0 % f c'
Location : 2ScSc5-19 & 1ScSc5-12 & 1ScSc5-11 (61 strands)
Beam length : 40.600 m JF = 75.8 % UTS
Date : 23-Apr-24 prepared by : TY Deflection: OK !

Ast = 0.00
2
s cp,f = Pe*ex/Wb + Pe/Ac = 82.10 kg/cm .
M 0 = Z * T cp,f = 437703.35 kg-m.
V0 = M 0/(M'/V') = 187675.00 kg.
Vc = 296189.92 kg.

* Cracking shear strength at web

Vc = Vt + Pv
Vt = 0.3*((f c')^0.5 + f pc)*bv*d = 92782.55 kg.
Vc = 143298.56 kg.

Vc, min = 143298.56 kg..

2
vs = vu/0.7 - vc = 22.68 kg/cm .

provided stirrups diameter = 10 12 13 16 mm.


2
Av = 1.57 2.26 2.65 4.02 cm .
stirrups space, s = Av*f y/(vs*bv)
s max = 14.97 21.56 42.17 63.87 cm.
VII. Control to point load T

DLA=0.3
4.7 19.0 19.0 (ton).

40.0 m.
16.0 4.0 5.0 15.0 (m).

19.447 23.242 (ton).

M mid = 370 ton-m.

* Stresses due to point load;

Slab top fiber : 56.6 kg/cm2. Ok!


Beam top fiber : 142.2 kg/cm2. Ok!
Bottom fiber : 0.5 kg/cm2. Ok!

VIII. Deflection control at the middle of span (" -"=downward, "+"=upward )

8.1. Deflection due to selfweight


Y = - 5/384 x q x L^4 / EI = -4.2 cm.
8.2. Deflection due to SDL
Y = - 5/384 x qDL x L^4 / EI - 1/48 x Pd x L^3 / EI = -0.8 cm.
8.3. Deflection due to T
Y = [appropriated formula] -2.1 cm.
8.4. Deflection due to live load
Y = - 5/384 x p x L^4 / EI - 1/48 x P x L^3 / EI = -2.2 cm.
8.5. Deflection due to effective prestress force
Y = 5/384 x (8xPxe/L^2) x L^4 / EI = +6.7 cm.

IX. Resume
Prestress force:
Pi = 762.823 ton, or 66.87 % UTS.
Pe = 670.118 ton, or 58.75 % UTS.
PJF = 864.080 ton, or 75.75 % UTS.
Elongation of strand due to stressing = 275 mm.

Deflection ; Short term Long term


Due to SW+SDL+T) = -7.1 -12.1 cm.
Due to SW+SDL+LL = -7.2 -12.2 cm.
Due to SW+SDL+T+PT = -0.4 -5.4 cm.
Due to SW+SDL+LL+PT = -0.6 -5.6 cm.
Due to live load only -2.2 OK ! cm.
Allowable defl.=L/ 800 = -5.0 CHECKED cm.

X. Rotation at support
At service condition: 1DL+1LL+1PT
R= 0.005776 rad

XI. Longitudinal displacement at beam end


due to elastic shortening DLe = 9 mm After erection of beam:
due to shrinkage DLs = 9 mm DLs+DLc+DLT = 30 mm
due to creep DLc = 14 mm
due to temperature DLT = 7 mm

XII. Vertical reaction at support


DL = 70.072 t SW = 38.037 t
LL = 31.939 t
1DL+1.5LL, Vu = 117.981 t  Bearing: [appropriated bearing]

XIII. Quantity
Weight of beam = 76.07 t
Weight of strand = 2.01 t
Concrete volume= 30.43 m3
Strand content= 66.18 kg/m3

_________________________________ __________________________
COPYRIGHT PT VSL INDONESIA PAGE 6 OF 6

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