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DESIGN OF INNOVATIVE PRESTRESSED STEEL -
CONCRETE COMPOSITE BRIDGE (50.0m span)
DESIGNED BY
Vikash Khatri Harshad Birajdar
(Research Scholar) (Research Scholar)
Dr. Pabitra Ranjan Maiti Dr. Pramod Kumar Singh
(Assistant Professor) (Professor)
DEPARTMENT OF CIVIL ENGINEERING
INDIAN INSTITUTE OF TECHNOLOGY
(BANARAS HINDU UNIVERSITY)
VARANASI-221005, INDIA
(April - 2013)
1
CONTENTS
S.N0. DESCRIPTION Page No.
1.0 Introduction 2
1.1 Shrinkage effect and transverse cracking of deck 2
1.2 Prestress in steel-concrete composite bridges 2
2.0 Typical design of 50.0 m span PSCC bridge 3
2.1 Details of ROB 3
2.2 Design parameters 3
2.3 Stages of construction 3
2.4 Codes used in the design 4
3.0 Summary of moments, shear and deflections 4
4.0 Calculation for prestress 5
4.1 Upward deflection due to prestressing force 6
4.2 Downward deflection due to horizontal component of prestressing force 6
4.3 Prestressing force 8
4.4 Design of cables 11
5.0 Bending stresses in longitudinal girder during erection 11
5.1 Stresses after prestressing 11
5.2 Stresses after SIDL and Live Load 12
5.3 Summary of stresses at critical points 13
5.4 Check for longitudinal girder overturning due to wind load 13
6.0 Check at Limit State of Strength 13
7.0 Design of shear connectors between deck slab and girders 15
8.0 Design of deck slab 16
9.0 Design of struts between cross girders 17
References 18
Appendix-I 19
Appendix-II 23
Appendix-III 28
Appendix-IV 29
Appendix-V 30
Appendix-VI 31
2
1.0 INTRODUCTION
Steel Concrete Composite (SCC) bridges are popularly constructed throughout the
World. Total shrinkage strain in deck slab concrete of SCC bridges may be taken as
0.0003 (as per IRC-22, 1986). For composite action to start, this strain must be first
overcome, for which flexural stress of 60 N/mm2 is required at the top fiber of the steel
girders. Therefore, assuming the top fibre stress of 60 N/mm2
due to self weight of the
girders and the deck slab concrete, and assuming permissible stress as 150 N/mm2, only
20% live load will be supported by the composite action and rest all the loads (80% of
total load) will be supported by the steel girders alone.
Thus, it is advantageous to prestress the deck slab, as well as provide vertical
support to the longitudinal girders at intermediate points, with the help of prestressing
cables anchored in deck slab and supported over cross girders (Drawing-2/9). Thus, the
concept of Prestressed Steel-Concrete Composite (PSCC) bridge is evolved.
1.1 Shrinkage effect and transverse cracking of deck
Radabaugh (2001) surveyed 52 transportation agencies in the United States and
Canada to evaluate the extent of early age transverse cracking. The researchers found that
over 100,000 bridges in the United States developed early transverse cracks.
The presence of early age transverse cracking in concrete bridge decks is often
what leads to the eventual structural deficiency of bridges in the long run because these
cracks permit the ingress of harmful substances (Kasim and Chen, 2006).
Folliard et al. (2003) concluded in their study on bridge decks that transverse
cracking was the most prevalent type of cracking in bridge decks and was most likely due to
shrinkage in hardened concrete. Tia et al. (2005) surveyed 249 four year old bridge decks in
Pennsylvania to investigate the extent and causes of deterioration in concrete bridge decks
and they found transverse cracks to be the most prevalent type of cracks in the deck slabs.
1.2 Prestress in steel-concrete composite bridges
Assuming the cost of High Tensile Steel (HTS) as approximately 1.5 times the
cost of Structural Steel (SS), a comparison of cost and weight ratios for HTS (fy = 2000
N/mm2) and SS ( fy = 250 N/mm
2) are given below.
Strength/unit cost ratio =
2000
cost 1.5250
cost 1.0
strengthfor HTS
strengthfor SS
= 5.3
Strength/unit weight ratio =
2000
1.0250
1.0
strengthfor HTS
weight
strengthfor SS
weight
= 8.0
3
In the PSCC bridge full dead load and part (50%) live load are supported by the
cables, and therefore, it is a very economical solution for long span bridges situated in
high seismicity areas. Also, due to longitudinal prestress in the deck slab, the deck slab
behaves like prestressed concrete railway sleeper having high durability and resistance
against fatigue loading (Singh, 2008).
2.0 TYPICAL DESIGN OF 50.0 m SPAN PSCC BRIDGE
A typical Road Over Bridge (ROB) given in GAD (Drawing-1/9) is designed with
the following data.
2.1 Details of ROB
Length of span = 47.8 m
Overall Length of span = 50.0 m
No. of main girders = 5
No. of cross girders (including end cross girders) = 7
Total deck width and carriageways width = 12.0 m and 7.5 m
Width of footpath = 1.5 m
Height and width of crash barrier = 1550 mm and 500 mm
Height and width of railing = 1550 mm and 250 mm
Thickness of deck slab = 220 mm
Thickness of haunch = 100 mm
Thickness of wearing coat = 80 mm
2.2 Design parameters
Steel used for girders is Fe250 (Mild steel) fy = 250 N/mm2
Grade of concrete = M 45
Grade of HYSD bar conforming to IS:1786 = Fe 500
Short term modulus of elasticity for concrete = 33500 N/mm2
Modulus of elasticity of structural steel = 211000 N/mm2
Short term modulus ratio for transient loading = 6.3
Permissible compressive stress in deck slab = 15.00 N/mm2
Unit weight of deck concrete = 25 kN/m3
Unit weight of wearing coat = 22 kN/m3
Unit weight of structural steel = 78.5 kN/m3
Permissible stress in girder = 0.62fy = 155.0 N/mm2
Live Loads:
The bridge is designed for; two lanes class –A and single lane 70R loading.
Sectional properties of the bridge members are calculated in Appendix-I.
2.3 Stages of construction
There are four stages of construction as:
4
(i) Launching of longitudinal girders.
(ii) Erection of cross girders and casting of deck slab.
(iii) Superimposed dead load (SIDL): Wearing coat, and railings are fixed.
(iv) Prestressing: This is done for counteracting DL, SIDL, and 50% of Footpath Live
Load and Live Load with impact.
The bending moments and shear forces for various stages of construction are
found at critical sections with the help of STAAD.Pro software (Appendix -II).
Critical Sections
The bending and shear stress are checked at the following critical sections.
(i) Mid-span,
(ii) Splice locations,
(iii) Curtailment points, and
(iv) Supports.
2.4 Codes used in the design
The following codes are used in the design.
i. IRC: 6-2000, “Standard specifications and Code of Practice for Road Bridges,
Section II, Loads and Stresses”, Indian Road Congress, New Delhi.
ii. IRC: 18-2000, “Design Criteria for Prestressed Concrete Road Bridges (Post-
Tensioned Concrete)”, Indian Road Congress, New Delhi.
iii. IRC: 21-1994, “Code of Practice for Road Bridges, Section III, Cement Concrete
(Plain and Reinforced)”, Indian Road Congress, New Delhi.
iv. IRC: 22-1986, “Code of Practice for Road Bridges, Section VI, Composite
Construction”, Indian Road Congress, New Delhi.
v. IRC: 24-2001, “Code of Practice for Road Bridges, Section V, Steel Road Bridges”,
Indian Road Congress, New Delhi.
vi. IRC: 87-1984, “Guidelines for The Design and Erection of Falsework for Road
Bridges”, Indian Road Congress, New Delhi.
vii. IS 1343:1999, “Code of Practice for Prestressed Concrete”, Bureau of Indian
Standards, New Delhi.
viii. IS 2062: 1999, “Steel for General Purposes”, Bureau of Indian Standards, New Delhi.
ix. IS 456: 2000, “Plain and Reinforced Concrete - Code of Practice”, Bureau of Indian
Standards, New Delhi.
x. IS 800: 2007, “General Construction in Steel - Code of Practice”, Bureau of Indian
Standards, New Delhi.
xi. IS 2090: 1999, “Specification for High Tensile Steel Bars Used in Prestressed
Concrete”, Bureau of Indian Standards, New Delhi.
3.0 SUMMARY OF MOMENT, SHEAR AND DEFLECTION
Summary of moment, shear and deflection obtained from STAAD output, at all the
critical points are given in Table 1 (Ref. STAAD file, Appendix-II).
5
Table 1: Summary of moment, shear and deflection
At support (x = 0) Moment (kNm) Shear (kN) Deflection (mm)
Self weight 0.2 127 0.0
Deck slab 0.0 589 0.0
SIDL 0.02 430 0.0
FPLL 0.6 90.2 0.0
LL with IF 1.15 1.2 381.5 0.0
At splice point-1 (x = 5.15) Moment (kNm) Shear (kN) Deflection (mm)
Self weight 690.9 123.8 12.7
Deck slab 2515.0 409.9 43.2
SIDL 1244.8 392.8 10.0
FPLL 376.3 53.8 2.9
LL with IF 1.15 1151.8 206.0 7.1
At curtailment point-1 (x =10.0) Moment (kNm) Shear (kN) Deflection (mm)
Self weight 1230.5 98.0 22.6
Deck slab 4241.5 302.4 76.3
SIDL 2052.9 246.6 17.8
FPLL 600.2 41.8 5.1
LL with IF 1.15 1867.0 164.6 12.9
At Splice Point-2 (x = 17.65) Moment (kNm) Shear (kN) Deflection (mm)
Self weight 1784.2 43.0 32.6
Deck slab 5906.0 138.0 109.5
SIDL 2758.7 181.4 25.7
FPLL 775.2 27.0 7.3
LL with IF 1.15 2439.8 148.0 18.9
At mid section (x = 23.9) Moment (kNm) Shear (kN) Deflection (mm)
Self weight 1930.2 3.7 35.3
Deck slab 6323.9 4.2 118.4
SIDL 2896.1 37.4 27.8
FPLL 797.5 19.9 7.9
LL with IF 1.15 2452.0 135.5 20.3
Total deflection due to self weight, deck slab, SIDL and 50% of FPLL and LL with
impact, at mid section = 195.6 mm.
This deflection shall be eliminated by prestressing.
4.0 CALCULATION FOR PRESTRESS
Prestressing force required in the cables for counteracting DL, SIDL, FPLL, LL
with impact, and 50% LL hogging deflections are calculated as given below.
6
4.1 Upward deflection due to prestressing force
Total number of prestressing cables = 14
Change in angle of cable at X-girders = 2.5 degree
Angle of cable with horizontal at the ends (α) = 6.25 degree
α
Neutral Axis
(NA)
e
PH
PV
PR
R
R
R
R
Cables
Fig. 5 Upward reaction from cable to cross girders
As shown in Fig. 5 the vertical reaction to cross girders from cables, tanHR P
where, HP is the horizontal component of the prestressing force.
Upward deflection due to equivalent uniformly distributed load ( w ) =45
384
wL
EI
where, w =5R
L
Therefore, vertical deflection ( v ) due to prestressing force 325
384
RL
EI
or 325 tan
384
Hv
L P
EI
… (1)
4.2 Downward deflection due to horizontal component of prestressing force
Downward deflection ( 0 ) due to horizontal component of the
prestressing force (Fig. 6) is calculated as given below.
δ0
α
NA
e
PH
PV
P
Cables
Fig. 6 Vertical deflection ( 0 ) due to HP
7
Using the beam bending diagram (Fig. 7), we get;
sHEP e
I y
where,
- Strain in the girder
SE - Modulus of elasticity of girder steel
I - Moment of Inertia
y - Distance of neutral axis from girder top
e - Eccentricity of horizontal prestress force from neutral axis
∆x
θ
y
L
δ0
R
Fig. 7 Beam bending diagram
Also,
2x x
andy L
Solving the above equations we get;
2
HP eL
I
Also,
02 cosL R and R R
Therefore, vertical deflection due to horizontal component of the prestressing
force HP is given by;
0 1 cos ,2 2
HP eLLwhere
EI
radians … (2)
8
4.3 Prestressing force
Prestress is applied for eliminating the following deflections in addition to
overcoming the shrinkage strain of the deck slab concrete.
(i) Deflection due to self weight of girders, deck slab and SIDL.
(ii) 50 % of LL hogging deflection
(iii) Deflection due to horizontal component of the prestressing force.
From STAAD results, deflections to be counteracted by prestressing are:
Deflection due to self weight of girder = 35.3 mm
Deflection due to deck slab weight = 118.4 mm
Deflection due to SIDL = 27.8 mm
50 % of LL hogging deflection = 14.1 mm
Total deflection to be counteracted by prestress to eliminate shrinkage strain of
deck slab concrete and 50 % of LL hogging deflection,
= 35.3+118.4 + 27.8 + 14.1 = + 195.6 mm
Here, girder section alone will be effective till the shrinkage of concrete is
eliminated. Thereafter, the composite section will become effective.
eg
∆ g + δg
α
0.0003NA girder
Hg
Vg
Pg
Load due to self weight, deck slab and SIDL
yg
Cables
Fig. 8 Deflection due to DL and horizontal component of prestress (with girder section only)
Deflection due to self weight of girders, deck slab and SIDL ( g ) and deflection due
to horizontal component of the prestress ( g ) with girder section only are shown in Fig. 8.
Horizontal component of prestress (Fig. 8) required to counteract shrinkage strain
of deck slab concrete is given by the bending equation,
2 g g sh
g g
H e
I y
9
or 1 1
2 2
sh g sh s g
g
g g g g
I E IH
e y e y
… (3)
where,
gH - Horizontal component of prestress force required to counteract shrinkage
strain of deck slab concrete (kN).
sh - Shrinkage stress in deck slab concrete (N/mm2)
g - Shrinkage strain at girder top
gI - Moment of Inertia of girder section only
ge - Eccentricity of horizontal prestress force from neutral axis (mm)
gy - Distance of neutral axis from girder top (mm)
gd - Net upward downward deflection at mid span (mm)
gR - Vertical reaction at cable support (kN).
Flexibility matrix for unit cable force along gP is calculated using equations 2 and 3, and
is given below.
g
g
7
P 1
0.99406
0.10887
0.1045
2.1 10
g
g
g
H
R
d
where,
gP - Prestress in cable to counteract shrinkage strain of deck slab concrete (kN).
Since, shrinkage strain at girder top = 0.0003, multiplying above matrix with
0.0003/ 72.1 10 , we get the following values for deck slab shrinkage elimination as:
g
g
P 1429
1420
156
149.2
0.0003
g
g
g
H
R
d
Deflection counteracted by horizontal component of prestressing force ( gH ) up to
the elimination of shrinkage effect with girder section alone = -149.2 mm
Therefore, net deflection to be counteracted by prestress after elimination of
shrinkage effect with composite action, is given as the difference of total deflection and
deflection for elimination of shrinkage strain as,
= 195.6 – 149.2 = 46.4 mm
10
Deflection (C ) due to part DL, and deflection ( C ) due to horizontal component
of the part prestress after elimination of shrinkage strain (with composite section) are
shown in Fig. 9.
∆C + δC
αNA compositeHC
VC
PC
Load due to self weight, deck slab and SIDL
ycec
Cables
Fig. 9 Deflection due to part prestress and horizontal component of prestress (with
composite section)
Flexibilty matrix for the composite section is given as:
c
3
P 1
0.99406
0.10887
5.68 10
0.0708
c
c
c
c
H
R
d
Thus, multiplying the flexibility matrix by 46.4/0.0708, we get;
cP 654
651
71.2
3.71
46.4
c
c
c
c
H
R
d
where,
cP - Prestress in cable with composite section (kN)
cH - Horizontal component of prestress in deck slab with composite section (kN)
cR - Vertical reaction at cable support (kN)
cd - Net upward downward deflection at mid span (mm)
c - Stress in deck slab (N/mm2)
Therefore, total prestress required in each of the 14 cables (excluding losses),
= 1429 + 654 = 2083 kN
11
Calculation of losses in prestress is given in Appendix-III.
Therefore, total prestressing force required in each cable including losses,
P = 2083 + 58.2 + 117.2 + 10.5 + 92.2 = 2301 kN
4.4 Design of cables
Using 19T15 STD Prestressing Cables,
Breaking load of each cable = 4313 kN
Cross-sectional area of each cable = 2635 N/mm2
Breaking stress = 1636.8 N/mm2
Cable stress in service condition shall be limited to 60% of breaking stress.
60% of breaking stress = 982.1 N/mm2
Prestressing the 17 strands at 878.7 N/mm2 (53.7 % of breaking stress),
Prestressing force in each cable = 2315.4 kN > 2301.0 kN, O.K.
Number of emergency strands in each cable = 2
5.0 BENDING STRESSES IN LONGITUDINAL GIRDER DURING ERECTION
Permissible elastic critical stresses are calculated at different stages as per Clause
no. 508.6.2 of IRC: 24-2001 (Ref. Appendix IV).
Bending stresses in longitudinal girder during erection stages are given in Table 2.
Table 2: Bending stresses in longitudinal girder during erection stages
Permissible bending stress in steel girders before connection of cross girders =36.8 N/mm2
Permissible bending stress in steel girders after connection of cross girders = 161.8 N/mm2
Therefore, longitudinal girder stresses are found safe during erection stages up to
casting of deck slab concrete as per Clause 202.3 of IRC:6 2000 Code.
5.1 Stresses after prestressing
Stresses in longitudinal girder after prestressing are given in Table 3.
Construction
stage\Location
Girder
position
After launching of
longitudinal girder ( N/mm2)
After launching of
deck slab ( N/mm2)
At splice
point-1
Girder bottom 9.9 46.0
Girder top 12.1 56.0
At curtailment
Point
Girder bottom 17.6 78.4
Girder top 21.5 95.5
At splice
point-2
Girder bottom 25.6 110.3
Girder top 31.1 134.2
At mid span Girder bottom 27.7 118.3
Girder top 33.7 144.1
12
Table 3: Stresses in longitudinal girder after prestressing
Permissible stress in steel girder = 161.8 N/mm2
Permissible stress in deck slab = 15.0 N/mm2 (IRC 21- Table 9)
Therefore, longitudinal girder stresses are found to be safe after prestressing as
per Clause 202.3 of IRC:6 2000 Code.
5.2 Stresses after SIDL and Live Load
Stresses in the girder and deck slab after SIDL and live load as obtained from the
STAAD output are given in Table -4.
Table 4: Girder Stress due to SIDL and live load
Permissible bending stress in longitudinal girder during service condition =0.62fy=155.0N/mm2
(IRC 24-2001, Table 6.2)
Construction
stage\Location Girder position
After elimination of
shrinkage effect (N/mm2)
After total
prestressing (N/mm2)
At splice
point-1
Girder bottom 63.3 64.9
Girder top 77.1 82.3
Deck slab top 0.0 3.0
At curtailment
Point
Girder bottom 63.3 64.9
Girder top 77.1 82.3
Deck slab top 0.0 3.0
At splice
point-2
Girder bottom 63.3 64.9
Girder top 77.1 82.3
Deck slab top 0.0 3.0
At mid span
Girder bottom 63.3 64.9
Girder top 77.1 82.3
Deck slab top 0.0 3.0
Critical
points Girder position
Stresses after
SIDL (N/mm2)
Stresses after
live load (N/mm2)
At splice
point-1
Girder bottom 15.1 33.6
Girder top 4.6 10.3
Deck slab top 4.1 5.4
At curtailment
Point
Girder bottom 24.9 54.8
Girder top 7.6 16.8
Deck slab top 4.8 6.9
At splice
point-2
Girder bottom 33.5 72.5
Girder top 10.3 22.3
Deck slab top 5.4 8.2
At mid span
Girder bottom 35.1 74.5
Girder top 10.8 22.9
Deck slab top 5.5 8.3
13
Permissible bending stress in deck slab during service condition = 15.0 N/mm2 (IRC 21-Table 9)
Therefore, the structure is safe in service condition.
5.3 Summary of stresses at critical points in service condition including temperature
Differential temperature effects as per IRC-6, Clause 218.4 and IRC-21, Clause
304.9.1 are calculated in Appendix-V.
Summary of stresses at all critical points in service condition are given in Table 5.
Stresses due to self weight, deck slab and SIDL are counteracted by prestressing. Hence
in service condition, stresses occur only due to 50 % of FPLL and LL with impact.
Table 5: Summary of stresses (N/mm2) at critical points
Stress at critical point\
Load case
At Splice Point 1 At Curtailment At Splice Point 2 At Mid Section
Slab
Top
Girder
Bottom
Girder
Top
Slab
Top
Girder
Bottom
Girder
Top
Slab
Top
Girder
Bottom
Girder
Top
Slab
Top
Girder
Bottom
Girder
Top
Stresses due to FPLL
+ LL with Impact 5.4 -33.6 10.3 6.9 -54.8 16.8 8.2 -72.5 22.3 8.3 -74.5 22.9
Differential
Temperature 4.3 -9.0 32.0 4.3 -9.0 32.0 4.3 -10.7 30.4 4.3 -10.7 30.4
Total stress in service
condition with
temperature stresses
9.7 -42.6 42.3 11.2 -63.8 48.8 12.5 -83.2 52.7 12.7 -85.2 53.3
Permissible stress in
service condition with
temperature stresses
15.0 -148.8 148.8 15.0 -148.8 148.8 15.0 -148.8 148.8 15.0 -148.8 148.8
Therefore, the girder and the deck slab are found to be safe in the service condition with
temperature effect.
5.4 Check for longitudinal girder overturning due to wind load
Longitudinal girders shall be prevented against overturning in wind condition by
suitable cross bracing between them, until the cross girders are connected.
6.0 CHECK AT LIMIT STATE OF STRENGTH
The calculation for the capacity of bridge at Limit State of Strength as per clause
5.1 of BIS 800:2007, is as follows and the result is given in Table 6.
As shown in Fig. 10 for Limit State of Strength, the ultimate moment ( UM ) at
service state can be calculated as given below.
Number of cables per girder = 14/5
14
(a) PSCC (b) Stress (c) Stress in (d) Stress at Limit
girder before LL LL condition State of Strength
Fig. 10 Stress distribution in PSCC bridge girder
The value of y is calculated from the equilibrium of forces (Fig. 10.d).
Force of compression,
C = (45/1.5) x [220x2500+700x100] + (600x(y-220-100)) x (250/1.15)
Force of tension,
T = (600x(40-(y-220-100)))x(250/1.15)+(2000x12)x(250/1.15) +
(800x40)x (250/1.15)+(14/5)x2635x(1637/1.15)
Therefore, y = 355.6 mm
Now, the ultimate moment of resistance of the composite section,
MU = (45/1.5)x(220x2500)x(355.6-220/2)+(45/1.5)x(100x700)x(355.6-220-100/2)
+ (600x(355.6-220-100))x(250/1.15)x((355.6-220-100)/2) + (600x(40-(355.6-220-100)))
x(250/1.15)x(40-(355.6-220-100))/2 + (2000x12)x(250/1.15)x(2000/2+(40-(355.6-220-
100))) + (14/5)x2635x(1637/1.15)x(220+100+40+2000+40-355.6+58/2) = 31332 kNm
Table 6: Moment carrying capacity for the PSCC bridge (kNm)
Total DL + LL
Moment, (M)
Moment at Limit State
of Strength (MU)
Ratio
(MU/M)
14400 31332 2.2
15
Hence, at the Limit State of Strength, the PSCC bridge will carry 2.2 times of the total
load in service condition.
7.0 DESIGN OF SHEAR CONNECTERS BETWEEN DECK SLAB AND GIRDERS
Design of shear connectors between deck slab and girders is done as per Clause
no. 611.4.1.3 and 611.5 of IRC: 22-1986 and 508.4.5 of IRC: 24-2001.
Horizontal shear at junction of deck slab and girder, H = V x A x y / I
For SIDL acting on composite section
Maximum shear in steel section due to SIDL (V) = 431 kN
Cross sectional area of effective deck section (A)
= (2.5 x 0.20 + 0.70 x 0.10) / 6.3 = 0.08 m2
Moment of inertia about major axis (I) = 0.09 m4
CG of slab from top of composite girder
= (2.5 x 0.2 x 0.12 + 0.7 x 0.1 x 0.30) / (2.5 x 0.2 + 0.70 x 0.1) = 0.1 m
CG of slab from CG of composite girder (Y) = 0.983 – 0.1 = 0.883 m
Horizontal shear force (H) = 431 x 0.08 x 0.883 / 0.09 = 377 kN/m
For FPLL and LL with impact acting on composite section
Maximum shear in steel section due to FPLL and LL with impact (V) = 943.3 kN
Cross sectional area of effective deck section (A)
= (2.5 x 0.20 + 0.70 x 0.010) / 6.3 = 0.08 m2
Moment of inertia about major axis (I) = 0.09 m4
CG of slab from top of composite girder
= (2.5 x 0.2 x 0.12 + 0.7 x 0.01 x 0.30) / (2.5 x 0.2 + 0.70 x 0.01) = 0.1 m
CG of slab from CG of composite girder (Y) = 0.983 – 0.1 = 0.883 m
Horizontal shear force (H) = 943.3 x 0.08 x 0.883 / 0.09 = 824.2 kN/m
Total horizontal shear force = 377 + 824.2 = 1201.2 kN/m
For restraining compression flange
To restrain compression flange laterally throughout its length, shear connectors shall be
capable of 2.5% of maximum compressive force in the top flange.
Maximum bending stress at top flange of girder = 159.1 N/mm2
Axial compressive force in the top flange = 159.1 x (0.040 x 0.60) x 1000 = 3818.4 kN/m
Shear force resisted by connector 2.5% of 3818.4 = 95.5 kN/m
Shear connectors has been designed from the consideration of fatigue strength of
connector and ultimate flexural strength of the composite
Diameter of stud used (d) = 30.0 mm
Provide height of stud (h) = 200 mm
Number of stud provided in one row (horizontally) = 3
Minimum clear edge distance of stud = 100.00 mm
Centre to centre distance between studs = 200.00 mm
Characteristics strength of concrete (fck) = 45.00 N/mm2
Safe shear resistance of shear connector (4.8 × d × h × sqrt(fck)) = 217.3 kN
Design shear force for fatigue consideration = 1201.2 kN/m
16
Spacing of shear connectors required = 180.9 mm
Provide spacing of shear connectors = 150.0 mm
Shear connecters between deck slab and Cross girder Diameter of stud used (d) = 30.0 mm
Provide height of stud (h) = 200 mm
Number of stud provided in one row (horizontally) = 2
Minimum clear edge distance of stud = 100.00 mm
Centre to centre distance between studs = 200.00 mm
Characteristics strength of concrete (fck) = 45.00 N/mm2
Safe shear resistance of shear connector (4.8 × d × h × sqrt(fck)) = 157.3 kN
Design shear force for fatigue consideration = 967.2 kN/m
Spacing of shear connectors required = 120.9 mm
Provide spacing of shear connectors = 125.0 mm
8.0 DESIGN OF DECK SLAB
(1) Live Load Moment:
Effective width at support = 2.48× (L/2)(1-0.5) = 1.395m
Impact factor = 1.15 (Clause 211.2 of I.R.C. 6-2000)
Load Intensity = 100×1.15/1.395 = 82.43kN/m
(2) Moment due to Live Load = 46.36 kNm/m
(3) Moment due to Dead Load + Wearing Coat = 3.269 kNm/m
Total moment at the support = 46.36 + 3.269 = 49.63 kNm/m
Calculation of design parameters
Grade of Concrete = M45
Grade of Steel = Fe 500
Permissible Stresses
σst = 200 N/mm2
σcbc = 15 N/mm2
Design basic parameters
r = σst/ σcbc = 13.33,
m = 6.3
k = m/(m+r) = 0.3209
j = 1 – k/3 = 0.8930
q = 0.5×σcbc×k×j = 2420.52 kN/m2
Clear cover = 40
Dia. of main bar = 16
Dia. of distributed bar = 10
Computation of reinforcement
Required depth = 143.20 mm
Minimum depth required = 220 – (40+10+8) = 162 mm ……………..OK
17
Depth provided = 192 mm
Ast required = 1447 mm2
Spacing = (1000 × 201)/935 = 138.9 mm
Provide 16ϕ @ 125mm c/c over full length at the bottom of slab
Reinforcement provided = 1608 mm2 >1447mm
2…………….OK
Provide 16ϕ @ 125mm c/c over full length at the top of slab
Reinforcement provided = 1608 mm2
Reinforcement above cross girder design as two way slab:
Bending moment for distribution reinforcement required
= 0.2×(DL moment) + 0.3×(LL moment) = 14.56 kNm
Distribution R/F required = 424 mm2
Spacing = 1000×113/ 424 = 266 mm
Provide 12ϕ @ 125 mm c/c over full length
Reinforcement provided = 753 mm2 > 424mm
2……….OK
Summary of transverse reinforcement
Top reinforcement of deck slab = 16 ϕ @ 125mm c/c
Cross sectional area of reinforcement = 1608 mm2
Bottom reinforcement of deck slab = 16 ϕ @ 125 mm c/c
Cross sectional area of reinforcement = 1608 mm2
Design of connections, splicing and stiffeners are given in Appendix-VI.
9.0 DESIGN OF STRUTS BETWEEN CROSS GIRDERS
For horizontal thrusts from the cables on the cross girders, due to change in angle
of the cable on the two sides of the cross girders, steel tubes as per IS-1161: 1987, are
used as struts between the cross girders. These tubes also served the purpose of encasing
the cables. Design of steel tubes used as struts is given in Table-7.
Table 7: Design of steel tubes used as struts
Strut Detail Steel Tube-1 Steel Tube-2 Steel Tube-3
Strutting between End cross girder
and cross girder-1
Cross girders
-1 and -2
Cross girders
-2 and -3
Nominal Diameter (mm) 90.0 110.0 150.0
Outer Diameter (mm) 101.6 127.0 168.3
Thickness (mm) 3.6 4.5 4.5
Cross section area (mm2) 1110 1730 2310
Least radius of gyration, r (mm) 34.7 43.3 57.9
leff/r ratio 149.9 120.1 89.8
Permissible stress (N/mm2) 45 63 88
Axial comp. capacity (kN) 50.0 109.0 203.3
Required axial comp. (kN) 0.0 100.4 200.8
18
The nine construction drawings as per above design calculation are enclosed herewith.
REFERENCES
i. Aravinthan T. (1999), "Flexural Behaviour and Design Methodology of
Externally Prestressed Concrete Beams", PhD thesis, Saitama University, Saitama
Japan.
ii. Aravinthan T. and Suntharavadivel T. G., (2007), "Effects of Existing Shear
Damage on Externally Post Tensioned Repair of Bent Caps", Journal of
Structural Engineering, 133(11), 1662-1669.
iii. Daly A. F. and Witarnawan W. (1997), “Strengthening of bridges using external
post-tensioning”, Transport Research Laboratory, Birkshire, U.K.
iv. Folliard K. J., Smith C., Sellers G., Brown M., and Breen J., (2003), “Evaluation
of Alternative Materials to Control Drying-Shrinkage Cracking in Concrete
Bridge Decks,” TDOT Report 4098-4.
v. Kasim.S.Y and Chen.A. (2006), “Conceptual design and analysis of steel concrete
composite bridges” Technical article.
vi. Kim H. Y., Jeong Y. J., Kim J. H. and Park S. K. (2005), “Steel concrete
composite deck for PSC Girder bridges.” Journal of Civil Engineering, ASCE,
Vol-9, No.-5, September.pp.385-390.
vii. Miyamoto A., Tei K., Nakamura H., and Bull J. W. (2000). "Behavior of
Prestressed Beam Strengthened with External Tendons." Journal of Structural
Engineering, 126(9), 1033-1044.
viii. Radabaugh R. D. (2001), “Investigation of Early Age Bridge Deck Cracking”,
Master Thesis, Purdue University, West Lafayette, IN.
ix. Singh P. K., (2008), ‘Fatigue in Concrete decks of cable stayed bridges’, Proc.
Int. Conf. on ‘Innovations in Structural Engineering and Construction’, Taylor &
Francis Group, London.
x. Tan K. H., Farooq M. A. and Ng C. K., (2001), “Behavior of Simple-Span
Reinforced Concrete Beams Locally Strengthened with External Tendons”, ACI
Structural Journal, 98(2), 174-183.
xi. Tia M., Subramanian R., Brown D. and Broward C., (2005), “Evaluation of
Shrinkage Cracking Potential of Concrete Used in Bridge Decks in Florida,”
Research Report, University of Florida, Sep., 129 pages.
19
Appendix-I
1.0 SECTIONAL PROPERTIES
Sectional properties of outer and inner girder (Fig. 1) are calculated at various locations where the
thicknesses of deck slab and girder properties are changing due to curtailment and change in thickness of
end block. Sectional dimensions of longitudinal girders at different location are given in Table 1.
Table 1: Sectional dimensions of longitudinal girders
Sectional dimensions between 0 to 1.1 m 1.1 to 2.9 m 2.9 to 10 m 10 to 23.9 m
Top flange (mm) 600 x 20
600 x 20
600 x 20
600 x 40
Web plate (mm) 1360 x 12 1700 x 12 2040 x 12 2000 x 12
Bottom flange (mm) 800 x 20
800 x 20
800 x 20
800 x 40
(a) 0 to 1.1 m (b) 1.1 to 2.9 m (c) 2.9 to 10.0 m (d) 10.0 to 23.9 m
Fig. 1 Sectional properties of main girders
Sectional properties of all cross girders (Fig. 2) are calculated at various locations where the depth
of girders is changing because of change in angle of cables. Sectional dimensions of all cross girders at
different location are given in Table 2.
(a) End Cross Girder (b) Cross Girder-1 (c) Cross Girder-2 (d) Cross Girder-3
Fig. 2 Sectional properties of cross girders
20
Table 2: Sectional properties of cross girders
Sectional properties End Cross
Girder Cross Girder-1 Cross Girder-2 Cross Girder-3
Top flange (mm) 400 x 20
400 x 20
400 x 20
400 x 20
Web plate (mm) 1360 x 12 960 x 12 1485 x 12 1660 x 12
Bottom flange (mm) 400 x 20
400 x 20
400 x 20
400 x 20
1.1 Sectional properties of longitudinal girders near end span (0 to 1.1 m)
Sectional properties of steel girder and composite girder, for span 0 to 1.1 m for both outer and
inner girders are given in Table-3.
Table 3: Sectional properties of steel girder and composite girder (0 to 1.1 m)
Girder Outer Inner
Sectional Properties Steel girder
only
Composite
girder
Steel girder
only
Composite
girder
Area 0.047 0.297 0.047 0.325
Moment of inertia 0.021 0.0896 0.020 0.092
Distance of neutral axis from girder bottom 0.65 1.67 0.65 1.69
Distance of neutral axis from girder top 0.75 0.274 0.75 0.289
Distance of neutral axis from slab bottom - 0.274 - 0.289
Distance of neutral axis from slab top - 0.626 - 0.610
Section modulus for girder bottom 0.0267 0.064 0.0267 0.065
Section modulus for girder top 0.0232 0.390 0.0232 0.381
Section modulus for slab bottom - 2.457 - 2.402
Section modulus for slab top - 1.076 - 1.138
1.2 Sectional properties of longitudinal girders (1.1 to 2.9 m)
Sectional properties of steel girder and composite girder, for span 1.1 to 2.9 m for both outer and
inner girders are given in Table-4.
Table 4: Sectional properties of steel girder and composite girder (1.1 to 2.9 m)
Girder Outer Inner
Sectional Properties Steel girder
only
Composite
girder
Steel girder
only
Composite
girder
Area 0.0496 0.214 0.0496 0.232
Moment of inertia 0.0288 0.089 0.0288 0.090
Distance of neutral axis from girder bottom 0.815 1.735 0.815 1.757
Distance of neutral axis from girder top 0.925 0.005 0.925 0.017
Distance of neutral axis from slab bottom - 0.005 - 0.017
Distance of neutral axis from slab top - 0.565 - 0.543
Section modulus for girder bottom 0.0352 0.059 0.0352 0.060
Section modulus for girder top 0.0310 0.197 0.0310 6.143
Section modulus for slab bottom - 0.012 - 0.387
Section modulus for slab top - 1.145 - 1.218
1.3 Sectional properties of longitudinal girders (2.9 to 10 m)
Sectional properties of steel girder and composite girder, for span 2.9 to 10.0 m for both outer and
inner girders are given in Table-5.
21
Table 5: Sectional properties of steel girder and composite girder (2.9 to 10 m)
Girder Outer Inner
Sectional Properties Steel girder
only
Composite
girder
Steel girder
only
Composite
girder
Area 0.0525 0.131 0.0525 0.140
Moment of inertia 0.0379 0.0857 0.0379 0.0877
Distance of neutral axis from girder bottom 0.980 1.625 0.980 1.667
Distance of neutral axis from girder top 1.10 0.455 1.10 0.423
Distance of neutral axis from slab bottom - 0.455 - 0.423
Distance of neutral axis from slab top - 0.675 - 0.643
Section modulus for girder bottom 0.0445 0.060 0.0445 0.061
Section modulus for girder top 0.0396 0.215 0.0396 0.237
Section modulus for slab bottom - 1.352 - 1.493
Section modulus for slab top - 0.911 - 0.982
1.4 Sectional properties of longitudinal girders (10 to 23.9 m)
Sectional properties of steel girder and composite girder, for span 10.0 to 23.9 m for both outer
and inner girders are given in Table-6.
Table 6: Sectional properties of steel girder and composite girder (10 to 23.9 m)
Girder Outer Inner
Sectional Properties Steel girder
only
Composite
girder
Steel girder
only
Composite
girder
Area 0.080 0.159 0.080 0.167
Moment of inertia 0.0654 0.128 0.0654 0.131
Distance of neutral axis from girder bottom 0.938 1.56 0.938 1.59
Distance of neutral axis from girder top 1.142 0.522 1.142 0.489
Distance of neutral axis from slab bottom - 0.522 - 0.489
Distance of neutral axis from slab top - 0.742 - 0.709
Section modulus for girder bottom 0.0698 0.082 0.0698 0.082
Section modulus for girder top 0.0573 0.245 0.0573 0.269
Section modulus for slab bottom - 1.544 - 1.692
Section modulus for slab top - 1.086 - 1.167
1.5 Sectional properties of end cross girder
Sectional properties of steel girder and composite girder, for the end cross girders are given in Table-7.
Table 7: Sectional properties of steel girder and composite girder (end cross girder)
End Cross Girder
Sectional Properties Steel girder
only
Composite
girder
Area 0.043 0.113
Moment of inertia 0.012 0.030
Distance of neutral axis from girder bottom 0.70 1.20
Distance of neutral axis from girder top 0.70 0.200
Distance of neutral axis from slab bottom - 0.200
Distance of neutral axis from slab top - 0.420
Section modulus for girder bottom 0.0169 0.025
Section modulus for girder top 0.0169 0.148
Section modulus for slab bottom - 0.935
Section modulus for slab top - 0.444
22
1.6 Sectional properties of Cross Girder-1
Sectional properties of steel girder and composite girder for Cross Girder-1 are given in Table-8.
Table 8: Sectional properties of steel girder and composite girder (Cross Girder-1)
Sectional Properties of Cross Girder – 1 Steel girder
only
Composite
girder
Area 0.0392 0.110
Moment of inertia 0.008 0.021
Distance of neutral axis from girder bottom 0.60 1.05
Distance of neutral axis from girder top 0.60 0.145
Distance of neutral axis from slab bottom - 0.145
Distance of neutral axis from slab top - 0.365
Section modulus for girder bottom 0.014 0.020
Section modulus for girder top 0.014 0.145
Section modulus for slab bottom - 0.916
Section modulus for slab top - 0.364
1.7 Sectional properties of Cross Girder-2
Sectional properties of steel girder and composite girder, for Cross Girder-2 are given in Table-9.
Table 9: Sectional properties of steel girder and composite girder (Cross Girder-2)
Sectional Properties of Cross Girder – 2 Steel girder
only
Composite
girder
Area 0.051 0.121
Moment of inertia 0.022 0.053
Distance of neutral axis from girder bottom 0.91 1.50
Distance of neutral axis from girder top 0.91 0.32
Distance of neutral axis from slab bottom - 0.32
Distance of neutral axis from slab top - 0.54
Section modulus for girder bottom 0.024 0.035
Section modulus for girder top 0.024 0.165
Section modulus for slab bottom - 1.04
Section modulus for slab top - 0.616
1.8. Sectional properties of Cross Girder-3
Sectional properties of steel girder and composite girder, for Cross Girder-3 are given in Table-10.
Table 10: Sectional properties of steel girder and composite girder (Cross Girder-3)
Sectional Properties of Cross Girder – 3 Steel girder
only
Composite
girder
Area 0.056 0.126
Moment of inertia 0.030 0.070
Distance of neutral axis from girder bottom 1.03 1.65
Distance of neutral axis from girder top 1.03 0.396
Distance of neutral axis from slab bottom - 0.396
Distance of neutral axis from slab top - 0.62
Section modulus for girder bottom 0.029 0.043
Section modulus for girder top 0.029 0.178
Section modulus for slab bottom - 1.12
Section modulus for slab top - 0.720
23
Appendix-II
The grillage diagram of bridge showing member numbers is shown in Fig. 1.
Fig. 1 Grillage diagram of bridge
The STAAD data file for calculation of shear, bending moment and deflection under various loads
is given below.
Data file:
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 12-Oct-11
END JOB INFORMATION
INPUT WIDTH 79
UNIT METER KN
JOINT COORDINATES
1 0 0 0; 2 0 0 1; 3 0 0 3.5; 4 0 0 6; 5 0 0 8.5; 6 0 0 11; 7 0 0 12; 8 2.9 0 0; 9 2.9 0 1; 10 2.9 0 3.5; 11 2.9 0 6;
12 2.9 0 8.5; 13 2.9 0 11; 14 2.9 0 12; 29 11.9 0 0; 30 11.9 0 1; 31 11.9 0 3.5; 32 11.9 0 6; 33 11.9 0 8.5;
34 11.9 0 11; 35 11.9 0 12; 57 23.9 0 0; 58 23.9 0 1; 59 23.9 0 3.5; 60 23.9 0 6; 61 23.9 0 8.5; 62 23.9 0 11;
63 23.9 0 12; 85 35.9 0 0; 86 35.9 0 1; 87 35.9 0 3.5; 88 35.9 0 6; 89 35.9 0 8.5; 90 35.9 0 11; 91 35.9 0 12;
106 44.9 0 0; 107 44.9 0 1; 108 44.9 0 3.5; 109 44.9 0 6; 110 44.9 0 8.5; 111 44.9 0 11; 112 44.9 0 12; 113
47.8 0 0; 114 47.8 0 1; 115 47.8 0 3.5; 116 47.8 0 6; 117 47.8 0 8.5; 118 47.8 0 11; 119 47.8 0 12; 120 1.1 0
0; 121 1.1 0 1; 122 1.1 0 3.5; 123 1.1 0 6; 124 1.1 0 8.5; 125 1.1 0 11; 126 1.1 0 12; 127 46.7 0 0; 128 46.7
0 1; 129 46.7 0 3.5; 130 46.7 0 6; 131 46.7 0 8.5; 132 46.7 0 11; 133 46.7 0 12; 134 7.9 0 0; 135 7.9 0 1;
136 7.9 0 3.5; 137 7.9 0 6; 138 7.9 0 8.5; 139 7.9 0 11; 140 7.9 0 12; 141 15.9 0 0; 142 15.9 0 1; 143 15.9 0
3.5; 144 15.9 0 6; 145 15.9 0 8.5; 146 15.9 0 11; 147 15.9 0 12; 148 31.9 0 0; 149 31.9 0 1; 150 31.9 0 3.5;
151 31.9 0 6; 152 31.9 0 8.5; 153 31.9 0 11; 154 31.9 0 12; 155 39.9 0 0; 156 39.9 0 1; 157 39.9 0 3.5; 158
39.9 0 6; 159 39.9 0 8.5; 160 39.9 0 11; 161 39.9 0 12; 162 17.65 0 0; 163 17.65 0 1; 164 17.65 0 3.5; 165
17.65 0 6; 166 17.65 0 8.5; 167 17.65 0 11; 168 17.65 0 12; 169 30.15 0 0; 170 30.15 0 1; 171 30.15 0 3.5;
172 30.15 0 6; 173 30.15 0 8.5; 174 30.15 0 11; 175 30.15 0 12; 176 5.15 0 0; 177 5.15 0 1; 178 5.15 0 3.5;
179 5.15 0 6; 180 5.15 0 8.5; 181 5.15 0 11; 182 5.15 0 12; 183 42.65 0 0; 184 42.65 0 1; 185 42.65 0 3.5;
186 42.65 0 6; 187 42.65 0 8.5; 188 42.65 0 11; 189 42.65 0 12; 190 48.9 0 0; 191 48.9 0 1; 192 48.9 0 3.5;
193 48.9 0 6; 194 48.9 0 8.5; 195 48.9 0 11; 196 48.9 0 12; 197 -1.1 0 0; 198 -1.1 0 1; 199 -1.1 0 3.5; 200 -
1.1 0 6; 201 -1.1 0 8.5; 202 -1.1 0 11; 203 -1.1 0 12; 204 19.9 0 0; 205 19.9 0 1; 206 19.9 0 3.5; 207 19.9 0
6; 208 19.9 0 8.5; 209 19.9 0 11; 210 19.9 0 12; 211 27.9 0 0; 212 27.9 0 1; 213 27.9 0 3.5; 214 27.9 0 6;
215 27.9 0 8.5; 216 27.9 0 11; 217 27.9 0 12; 218 10 0 0; 219 10 0 1; 220 10 0 3.5; 221 10 0 6; 222 10 0
8.5; 223 10 0 11; 224 10 0 12; 225 37.8 0 0; 226 37.8 0 1; 227 37.8 0 3.5; 228 37.8 0 6; 229 37.8 0 8.5;
230 37.8 0 11; 231 37.8 0 12;
MEMBER INCIDENCES
24
1 1 2; 2 2 3; 3 3 4; 4 4 5; 5 5 6; 6 6 7; 7 8 9; 8 9 10; 9 10 11; 10 11 12;
11 12 13; 12 13 14; 25 29 30; 26 30 31; 27 31 32; 28 32 33; 29 33 34; 30 34 35;
49 57 58; 50 58 59; 51 59 60; 52 60 61; 53 61 62; 54 62 63; 73 85 86; 74 86 87;
75 87 88; 76 88 89; 77 89 90; 78 90 91; 91 106 107; 92 107 108; 93 108 109;
94 109 110; 95 110 111; 96 111 112; 97 113 114; 98 114 115; 99 115 116;
100 116 117; 101 117 118; 102 118 119; 116 1 120; 117 8 176; 131 106 127;
134 2 121; 135 9 177; 149 107 128; 152 3 122; 153 10 178; 167 108 129;
188 5 124; 189 12 180; 203 110 131; 206 6 125; 207 13 181; 221 111 132;
224 7 126; 225 14 182; 239 112 133; 240 120 8; 241 121 9; 242 122 10;
244 124 12; 245 125 13; 246 126 14; 247 127 113; 248 128 114; 249 129 115;
251 131 117; 252 132 118; 253 133 119; 254 120 121; 255 121 122; 256 122 123;
257 123 124; 258 124 125; 259 125 126; 260 127 128; 261 128 129; 262 129 130;
263 130 131; 264 131 132; 265 132 133; 273 134 135; 274 135 136; 275 136 137;
276 137 138; 277 138 139; 278 139 140; 286 141 142; 287 142 143; 288 143 144;
289 144 145; 290 145 146; 291 146 147; 299 148 149; 300 149 150; 301 150 151;
302 151 152; 303 152 153; 304 153 154; 305 200 4; 306 4 123; 307 123 11;
308 11 179; 309 179 137; 310 137 221; 311 221 32; 312 155 156; 313 156 157;
314 157 158; 315 158 159; 316 159 160; 317 160 161; 318 32 144; 319 144 165;
320 165 207; 321 207 60; 322 60 214; 323 214 172; 324 172 151; 325 162 163;
326 163 164; 327 164 165; 328 165 166; 329 166 167; 330 167 168; 331 151 88;
332 88 228; 333 228 158; 334 158 186; 335 186 109; 336 109 130; 337 130 116;
338 169 170; 339 170 171; 340 171 172; 341 172 173; 342 173 174; 343 174 175;
344 116 193; 351 176 177; 352 177 178; 353 178 179; 354 179 180; 355 180 181;
356 181 182; 357 183 106; 358 184 107; 359 185 108; 361 187 110; 362 188 111;
363 189 112; 364 183 184; 365 184 185; 366 185 186; 367 186 187; 368 187 188;
369 188 189; 370 176 134; 371 134 218; 372 177 135; 373 135 219; 374 178 136;
375 136 220; 378 180 138; 379 138 222; 380 181 139; 381 139 223; 382 182 140;
383 140 224; 384 29 141; 385 141 162; 386 162 204; 387 30 142; 388 142 163;
389 163 205; 390 31 143; 391 143 164; 392 164 206; 396 33 145; 397 145 166;
398 166 208; 399 34 146; 400 146 167; 401 167 209; 402 35 147; 403 147 168;
404 168 210; 405 57 211; 406 169 148; 407 148 85; 408 86 149; 409 149 170;
410 170 212; 411 59 213; 412 171 150; 413 150 87; 417 61 215; 418 173 152;
419 152 89; 420 62 216; 421 174 153; 422 153 90; 423 63 217; 424 175 154;
425 154 91; 426 85 225; 427 155 183; 428 86 226; 429 156 184; 430 87 227;
431 157 185; 434 89 229; 435 159 187; 436 90 230; 437 160 188; 438 91 231;
439 161 189; 440 190 191; 441 191 192; 442 192 193; 443 193 194; 444 194 195;
445 195 196; 446 197 198; 447 198 199; 448 199 200; 449 200 201; 450 201 202;
451 202 203; 452 113 190; 453 114 191; 454 115 192; 456 117 194; 457 118 195;
458 119 196; 459 197 1; 460 198 2; 461 199 3; 463 201 5; 464 202 6; 465 203 7;
466 204 57; 467 205 58; 468 204 205; 469 206 59; 470 205 206; 472 206 207;
473 208 61; 474 207 208; 475 209 62; 476 208 209; 477 210 63; 478 209 210;
479 211 169; 480 212 58; 481 211 212; 482 213 171; 483 212 213; 485 213 214;
486 215 173; 487 214 215; 488 216 174; 489 215 216; 490 217 175; 491 216 217;
492 218 29; 493 219 30; 494 218 219; 495 220 31; 496 219 220; 498 220 221;
499 222 33; 500 221 222; 501 223 34; 502 222 223; 503 224 35; 504 223 224;
505 225 155; 506 226 156; 507 225 226; 508 227 157; 509 226 227; 511 227 228;
512 229 159; 513 228 229; 514 230 160; 515 229 230; 516 231 161; 517 230 231;
START GROUP DEFINITION
MEMBER
_IG4 311 318 TO 324 331 332 390 TO 392 396 TO 398 411 TO 413 417 TO 419 430 -
434 469 473 482 486 495 499
_IG3 153 189 308 TO 310 333 TO 335 359 361 374 375 378 379 431 435 508 512
_IG2 167 203 242 244 307 336
_IG1 152 188 249 251 306 337
_OG4 387 TO 389 399 TO 401 408 TO 410 420 TO 422 428 436 467 475 480 488 493 -
501
25
_OG3 135 207 358 362 372 373 380 381 429 437 506 514
_OG2 149 221 241 245
_OG1 134 206 248 252
_CG1 273 TO 278 312 TO 317
_CG2 286 TO 291 299 TO 304
_CG3 49 TO 54
_ECG 1 TO 6 97 TO 102
_CB1 25 TO 30 73 TO 78 325 TO 330 338 TO 343 351 TO 356 364 TO 369 468 470 -
472 474 476 478 481 483 485 487 489 491 494 496 498 500 502 504 507 509 511 -
513 515 517
_CB2 254 TO 265
_CB3 7 TO 12 91 TO 96
_ECB 440 TO 451
_EOB 116 117 131 224 225 239 240 246 247 253 305 344 357 363 370 371 -
382 TO 386 402 TO 407 423 TO 427 438 439 452 TO 454 456 TO 461 463 TO 466 -
477 479 490 492 503 505 516
JOINT
END GROUP DEFINITION
DEFINE MATERIAL START
ISOTROPIC STEEL1
E 2.1e+008
POISSON 0.3
DENSITY 78.5
ALPHA 1.2e-005
DAMP 0.03
ISOTROPIC STEEL2
E 2.1e+008
POISSON 0.3
DENSITY 0
ALPHA 1.2e-005
DAMP 0.03
END DEFINE MATERIAL
CONSTANTS
MATERIAL STEEL1 MEMB _OG1
MATERIAL STEEL1 MEMB _OG2
MATERIAL STEEL1 MEMB _OG3
MATERIAL STEEL1 MEMB _OG4
MATERIAL STEEL1 MEMB _IG1
MATERIAL STEEL1 MEMB _IG2
MATERIAL STEEL1 MEMB _IG3
MATERIAL STEEL1 MEMB _IG4
MATERIAL STEEL1 MEMB _CG1
MATERIAL STEEL1 MEMB _CG2
MATERIAL STEEL1 MEMB _CG3
MATERIAL STEEL1 MEMB _ECG
MATERIAL STEEL2 MEMB _CB1
MATERIAL STEEL2 MEMB _CB2
MATERIAL STEEL2 MEMB _CB3
MATERIAL STEEL2 MEMB _ECB
MATERIAL STEEL2 MEMB _EOB
**************************************************
MEMBER PROPERTY INDIAN
**************************************************
_CB1 PRIS AX 0.00001 IX 1e-005 IY 1e-006 IZ 1e-005
_CB2 PRIS AX 0.00001 IX 1e-005 IY 1e-006 IZ 1e-005
_CB3 PRIS AX 0.00001 IX 1e-005 IY 1e-006 IZ 1e-005
26
_ECB PRIS AX 0.00001 IX 1e-005 IY 1e-006 IZ 1e-005
_EOB PRIS AX 0.00001 IX 1e-005 IY 1e-006 IZ 1e-005
***************************************************
*STEEL ONLY PROPERTIES*
*_OG1 PRIS AX 0.047 IX 1e-005 IY 1e-006 IZ 0.021
*_IG1 PRIS AX 0.047 IX 1e-005 IY 1e-006 IZ 0.021
*_OG2 PRIS AX 0.0496 IX 1e-005 IY 1e-006 IZ 0.0288
*_IG2 PRIS AX 0.0496 IX 1e-005 IY 1e-006 IZ 0.0288
*_OG3 PRIS AX 0.0525 IX 1e-005 IY 1e-005 IZ 0.0379
*_IG3 PRIS AX 0.0525 IX 1e-005 IY 1e-005 IZ 0.0379
*_OG4 PRIS AX 0.08 IX 1e-005 IY 1e-005 IZ 0.0654
*_IG4 PRIS AX 0.08 IX 1e-005 IY 1e-005 IZ 0.0654
*_ECG PRIS AX 0.0323 IX 1e-005 IY 1e-006 IZ 0.01
*_CG1 PRIS AX 0.0299 IX 1e-005 IY 1e-006 IZ 0.0071
*_CG2 PRIS AX 0.0372 IX 1e-005 IY 1e-006 IZ 0.0184
*_CG3 PRIS AX 0.04 IX 1e-005 IY 1e-006 IZ 0.0246
*SHORT TERM PROPERTIES*
_OG1 PRIS AX 0.297 IX 1e-005 IY 1e-006 IZ 0.0896
_IG1 PRIS AX 0.325 IX 1e-005 IY 1e-006 IZ 0.092
_OG2 PRIS AX 0.214 IX 1e-005 IY 1e-006 IZ 0.089
_IG2 PRIS AX 0.232 IX 1e-005 IY 1e-006 IZ 0.09
_OG3 PRIS AX 0.131 IX 1e-005 IY 1e-005 IZ 0.0857
_IG3 PRIS AX 0.140 IX 1e-005 IY 1e-005 IZ 0.0877
_OG4 PRIS AX 0.159 IX 1e-005 IY 1e-005 IZ 0.128
_IG4 PRIS AX 0.167 IX 1e-005 IY 1e-005 IZ 0.131
_ECG PRIS AX 0.318 IX 1e-005 IY 1e-006 IZ 0.0678
_CG1 PRIS AX 0.0998 IX 1e-005 IY 1e-006 IZ 0.0180
_CG2 PRIS AX 0.107 IX 1e-005 IY 1e-006 IZ 0.0437
_CG3 PRIS AX 0.11 IX 1e-005 IY 1e-006 IZ 0.0577
****************************************************
SUPPORTS
3 TO 5 115 TO 117 FIXED BUT MX MY MZ
2 6 114 118 FIXED BUT FZ MX MY MZ
DEFINE MOVING LOAD
*CLASS 70R WHEELED LOAD
TYPE 1 LOAD 85 85 85 85 60 60 40
DIST 1.37 3.05 1.37 2.13 1.52 3.96 WID 1.93
*CLASS A
TYPE 2 LOAD 13.5 13.5 57 57 34 34 34 34
DIST 1.1 3.2 1.2 4.3 3 3 3 WID 1.8
*CLASS 70R TRACKED LOAD
TYPE 3 LOAD 35 70 70 70 70 35
DIST 0.914 0.914 0.914 0.914 0.914 WID 2.06
**********************self weight of steel ********
LOAD 1 SELFWEIGHT
SELFWEIGHT Y -1
***************************
LOAD 2 DECK SLAB
MEMBER LOAD
***OG=2.25x0.9x25+2.25x3.6=58.725***LOAD DUE TO INCREASE IN SLAB THICKNESS AT
END***IG=2.5x0.87x25+0+2.25x3.6=65.25***
_OG1 UNI GY -58.725
_IG1 UNI GY -65.25
***OG=2.25x0.560x25+0+2.25x3.6=39.6***LOAD DUE TO INCREASE IN SLAB THICKNESS
BETWEEN X=1.1 TO X=2.9***IG=2.5x0.560x25+0+2.25x3.6=44***
_OG2 UNI GY -39.6
27
_IG2 UNI GY -44
***BETWEEN X=2.9 TO X=10.0 Curtailment point***OG=2.25x0.22x25+0.7x0.1x25+2.25x3.6=22.25
***DECK SLAB+HAUNCH + 3.6kN/m2 of Formwork***IG=2.5x0.22x25+0.7x0.1x25+2.25x3.6=24.5**
_OG3 UNI GY -22.25
_IG3 UNI GY -24.5
***BETWEEN X=10 TO X=27.8***OG=2.25x0.20x25+0.7x0.1x25+2.25x3.6=22.25***DECK
SLAB+HAUNCH +3.6kN/m2 of Formwork***IG=2.5x0.20x25+0.7x0.1x25+2.25x3.6=24.5***
_OG4 UNI GY -22.25
_IG4 UNI GY -24.5
******************************
LOAD 3 SIDL
MEMBER LOAD
********************CRASH BARRIER*************
_OG1 UNI GY -10
_OG2 UNI GY -10
_OG3 UNI GY -10
_OG4 UNI GY -10
*****************RAILING**********
_OG1 UNI GY -6
_OG2 UNI GY -6
_OG3 UNI GY -6
_OG4 UNI GY -6
*******************FOOTPATH**************
_OG1 UNI GY -3
_OG2 UNI GY -3
_OG3 UNI GY -3
_OG4 UNI GY -3
*****************WEARING COAT****************
_IG1 UNI GY -5
_IG2 UNI GY -5
_IG3 UNI GY -5
_IG4 UNI GY -5
***************************************
LOAD 4 FPLL
MEMBER LOAD
_OG1 UNI GY -7.5
_OG2 UNI GY -7.5
_OG3 UNI GY -7.5
_OG4 UNI GY -7.5
****************************************************
*2-LANES A
LOAD GENERATION 100
TYPE 2 -19.9 0 5.15 XINC 0.5
TYPE 2 -19.9 0 8.65 XINC 0.5
* 70R WHEELED
*LOAD GENERATION 100
*TYPE 1 -14.5 0 6.965 XINC 0.5
* 70R TRACKED
*LOAD GENERATION 100
*TYPE 3 -14.5 0 7.995 XINC 0.5
PERFORM ANALYSIS
FINISH
28
Appendix-III
1.0 CALCULATON OF LOSSES IN PRESTRESS
Losses due to slip in anchorage, elastic shortening, creep, and relaxation of steel are calculated below as per
Clause-18.5.5 of IS: 1343-1999.
1.1 Slip in anchorage
Loss due to slip in anchorage for 5 mm slip is,
1a s
s
EP A
L
= 58.2 kN
where,
1P - Loss of prestress in steel cable due to slip of anchorage
a - Slip of anchorage
sA - Area of cable
1.2 Elastic shortening
Loss due elastic shortening of cables: 2
2 cosg g g s
g
H e y AP
I
= 82.9 kN
1.3 Creep of concrete
Horizontal component of prestress required due to creep of deck slab concrete is given by:
/1 1
2 2
c c s ccr ccr
c c c c
f E E IIP
e y e y
= 10.5 kN, for prestressing at 28 days.
where,
crP - Horizontal component of prestress force required due to creep of deck slab
concrete
cr - Creep stress in deck slab concrete
sh - Shrinkage strain in deck slab concrete
- Creep coefficient
cf - Compressive stress in deck slab concrete
cE - Modulus of elasticity of deck slab concrete
1.4 Relaxation of steel
Loss of prestress in cable due to relaxation of steel is given by:
2
4 , 35 / 0.6s s s puP nA where N mm at f
4P 35 x 2635 = 92.2 kN
where,
s - Loss of stress due to relaxation of steel
29
Appendix-IV
1.0 CALCULATION OF CRITICAL STRESSES FOR LONGITUDINAL GIRDERS
Permissible elastic critical stresses are calculated at different stages as per Clause no. 508.6.2 of IRC:24-2001.
1.1 After launching of longitudinal girders
Cross sectional area of both flanges at the maximum BM zone (A1) = 56000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 28000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 0.5, and Coefficient associated with ψ (k1) = 0.7
Moment of inertia of both flanges at the maximum BM zone (I1) = 72 x 107 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 242.67 x 107 mm
4
Ratio of total moment of inertia of both flanges (β) = I1/I2 = 0.2967
Coefficient associated with β (k2) = -0.4
Effective length of compression flange (Leff) = 0.7 x 47800 = 33460 mm
Moment of inertia about minor axis (Iy) = I2 = 242.67 x 107 mm
4
Cross sectional area of girder (A) = 600 x 40 + 800 x 40 + 12 x 2000 = 80000 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 174.2 mm
Slenderness ratio, λ = Leff / ry = 192
Overall depth of beam (D) = 2080 mm, and Mean thickness of compression flange (T) = 30 mm
Ratio D/T = 69.3
Coefficient Y = 26.5 x 105 / λ
2 = 71.9, and Coefficient X = Y [1 + (LeffT/ryD)
2 / 20]
1/2 = 84.6
Lesser and greater distance of extreme fibre from neutral axis (c1 and c2) = 938 and 1142
Thickness of compression flange to web ratio (T/tw) = 2.5
Clear depth of web to thickness ratio (d/tw) = 2000/12 = 166.7
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 47.6 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 29.4 N/mm2
Permissible bending stress at erection stage = 1.25 x σbc = 36.8 N/mm2
1.2 After connection of cross beams
Cross sectional area of both flanges at the maximum BM zone (A1) = 28000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 28000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 1.0, and Coefficient associate with ψ (k1) = 1.0
Moment of inertia of both flanges at the maximum BM zone (I1) = 36 x 107 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 121.34 x 107 mm
4
Ratio of total Moment of inertia of both flanges (β) = I1/I2 = 0.2967
Coefficient associate with β (k2) = -0.4
Effective length of compression flange (Leff) = 1.2 x 8000 = 9600 mm
Moment of inertia about minor axis (Iy) = I2 = 121.34 x 107 mm
4
Cross sectional area of girder (A) = 600 x 20 + 800 x 20 + 12 x 2000 = 52000 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 152.8 mm
Slenderness ratio, λ = Leff / ry = 62.8
Overall depth of beam (D) = 2040 mm, and Mean thickness of compression flange (T) = 20 mm
Ratio D/T = 102
Coefficient Y = 26.5 x 105 / λ
2 = 671.9, and Coefficient X = Y [1 + (LeffT/ryD)
2 / 20]
1/2 = 678.2
Lesser and greater distance of extreme fibre from neutral axis (c1 and c2) = 942 and 1098
Thickness of compression flange to web ratio (T/tw) = 1.67
Clear depth of web to thickness ratio (d/tw) = 2000/12 = 166.7
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 477.2 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 129.5 N/mm2
Permissible bending stress at erection stage = 1.25 x σbc = 161.8 N/mm2
30
Appendix-V
CALCULATION OF DIFFERENTIAL TEMPERATURE STRESSES
Differential temperature occurs between the prefabrication steel girder and in-situ concrete deck
slab, and these results in the development of internal stresses. As per IRC-6 Fig. 10, Clause 218.4 and IRC-
21, Clause 304.9.1, the temperature stresses can be calculated as follows:
(1) At curtailment
Area of concrete = 55000 mm2
Modulus of elasticity of concrete = 33500 N/mm2
Uniform tensile stress induced in deck slab = 4.15 N/mm2
Direct stress in girder due to force = 26.15 N/mm2
Force due to temperature difference = 2.29 x106 N
Eccentricity of the force = 492 mm
Section Modulus
Bottom of girder = 52 x106 mm
3
Top of girder = 32 x106mm
3
Bottom of slab = 1.51 x109 mm
3
Top of slab = 9.56 x109 mm
3
Bending Stress
Bottom of girder = 17.2 N/mm3
Top of girder = 5.9 N/mm3
Bottom of slab = 0.6 N/mm3
Top of slab = 0.1 N/mm3
Resultant Stress
Bottom of girder = 8.95 N/mm3
Top of girder = 32.05 N/mm3
Bottom of slab = 3.55 N/mm3
Top of slab = 4.25 N/mm3
(2) At mid point
Area of concrete = 50000 mm2
Modulus of elasticity of concrete = 33500 N/mm2
Uniform tensile stress induced in deck slab = 4.15 N/mm2
Direct stress in girder due to force = 26.15 N/mm2
Force due to temperature difference = 2.08 x106 N
Eccentricity of the force = 639 mm
Section Modulus
Bottom of girder = 85.5 x106 mm
3
Top of girder = 319 x106 mm
3
Bottom of slab = 1.63 x109 mm
3
Top of slab = 1.20 x109 mm
3
Bending Stress
Bottom of girder = 15.5 N/mm3
Top of girder = 4.2 N/mm3
Bottom of slab = 0.8 N/mm3
Top of slab = 0.1 N/mm3
Resultant Stress
Bottom of girder = 10.65 N/mm3
Top of girder = 30.35 N/mm3
Bottom of slab = 3.35 N/mm3
Top of slab = 4.25 N/mm3
31
Appendix-VI
1.0 DESIGN OF CONNECTIONS BETWEEN WEB AND FLANGE OF LONGITUDINAL GIRDER
Design of weld between web, and top and bottom flanges of longitudinal girders is done as per Clause no.
512.2 of IRC: 24-2001.
1.1 Welds at junction between web and top flange
Horizontal shear at junction of web and top flange, H = V x A x y / I
For dead load and deck slab acting on steel section only
Maximum shear in steel section due to DL + Deck Slab = 127 + 589 = 716 kN
Cross sectional area of top flange (A) = 600 x 40 = 0.024 m2
Moment of inertia about major axis (I) = 0.065438 m4
CG of flange plate from top of girder = 0.02 m
CG of flange plate from CG of girder (Y) = 1.142 – 0.02 = 1.122 m
Horizontal shear force (H) = 716 x 0.024 x 1.122 / 0.065438 = 295 kN/m
For SIDL acting on composite section
Maximum shear in steel section due to SIDL = 430 kN
Cross sectional area of top flange (A) = 2500 x 220 /6.3 + 600 x 40 = 0.11 m2
Moment of inertia about major axis (I) = 0.14 m4
CG of slab and flange plate from top of girder = 0.47 m
CG of slab and flange plate from CG of girder (Y) = 0.633 + 0.47 = 1.1 m
Horizontal shear force (H) = 430 x 0.11 x 0.85 / 0.14 = 371.6 kN/m
For FPLL + LL with impact acting on composite section
Maximum shear in steel section due to LL = 471.7 kN
Cross sectional area of top flange (A) = 2500 x 220 /6.3 + 600 x 40 = 0.11 m2
Moment of inertia about major axis (I) = 0.14 m4
CG of slab and flange plate from top of girder = 0.47 m
CG of slab and flange plate from CG of girder (Y) = 0.633 + 0.47 = 1.1 m
Horizontal shear force (H) = 943.3 x 0.11 x 1.1 / 0.14 = 407.7 kN/m
Total horizontal shear at junction of web and top flange, H = 407.7 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 408 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
1.2 Welds at junction between web and bottom flange
Horizontal shear at junction of web and top flange, H = V x A x y / I
For DL and deck slab loads acting on steel section only
Maximum shear in steel section due to DL (V) = 127 + 589 = 716 kN
Cross sectional area of bottom flange (A) = 800 x 40 = 0.032 m2
Moment of inertia about major axis (I) = 0.065438 m4
CG of flange plate from bottom of girder = 0.020 m
CG of flange plate from CG of girder (Y) = 0.938 – 0.02 = 0.918 m
Horizontal shear force (H) = 716 x 0.032 x 0.918 / 0.065438 = 321.5 kN/m
32
For SIDL acting on composite section
Maximum shear in steel section due to DL (V) = 430 kN
Cross sectional area of bottom flange (A) = 800 x 40 = 0.032 m2
Moment of inertia about major axis (I) = 0.14 m4
CG of slab and flange plate from top of girder = 0.47 m
CG of flange plate from CG of girder (Y) = 1.447 - 0.47 = 0.977 m
Horizontal shear force (H) = 430 x 0.032 x 0.977 / 0.14 = 120.9 kN/m
For FPLL and LL with impact acting on composite section
Maximum shear in steel section due to DL (V) = 471.7 kN
Cross sectional area of top flange (A) = 800 x 40 = 0.032 m2
Moment of inertia about major axis (I) = 0.14 m4
CG of slab and flange plate from top of girder = 0.187 m
CG of flange plate from CG of girder (Y) = 1.677 - 0.187 = 1.49 m
Horizontal shear force (H) = 943.3 x 0.105 x 0.859 / 0.14 = 321 kN/m
Total horizontal shear at junction of web and top flange, H = 442 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 221 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
2.0 Design of curtailment plate
20 mm thick cover flange plate will be added in mid 27.8m (i.e. 10m from both ends)
Bending stress at curtailment point = 159.1 N//mm2
Area of curtailment plate = 600x20 = 12000 mm2
Tensile force at curtailment point on cover plate = 1909.2 kN
Nominal diameter of site snap headed bolt = 20.00 mm
Nominal diameter of bolt hole = 21.50 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Provide edge distance for 20 mm dia bolt = 50.00 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20.0 = 50.00 mm
Maximum pitch for 20 mm dia bolt = minimum of 200 or 12 x 30 = 200 mm
Number of shear plane = 1
Value of rivet in bearing = 21.5x20x300/1000 = 129.0 kN
Value of rivet in single shear = 3.14/4x21.52x100/1000 = 36.2 kN
Rivet Value = 36.2 kN
Number of bolt required = 1909.2/36.2 = 52.7
Number of bolts arranged per row = 30
Number of rows required = 2
3.0 Design of end cross girder
Permissible elastic critical stresses are calculated as per Clause no. 508.6.2 of IRC:24-2001.
Cross sectional area of both flanges at the maximum BM zone (A1) = 16000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 16000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 1.0
Coefficient associate with ψ (k1) = 1.0
Moment of inertia of both flanges at the maximum BM zone (I1) = 10.67 x 107 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 21.3 x 107 mm
4
Ratio of total Moment of inertia of both flanges (β) = I1/I2 = 0.5
33
Coefficient associate with β (k2) = 0.0
Effective length of compression flange (Leff) = 2500 mm
Moment of inertia about minor axis (Iy) = I2 = 21.3 x 107 mm
4
Cross sectional area of girder (A) = 400 x 20 + 400 x 20 + 12 x 1360 = 33400 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 80 mm
Slenderness ratio, λ = Leff / ry = 31.25
Overall depth of beam (D) = 1400 mm
Mean thickness of compression flange (T) = 20 mm
Ratio D/T = 74.5
Coefficient Y = 26.5 x 105 / λ
2 = 2713.6
Coefficient X = Y [1 + (LeffT/ryD)2 / 20]
1/2 = 2725.5
Lesser distance of extreme fibre from neutral axis (c1) = 745
Greater distance of extreme fibre from neutral axis (c2) = 745
Thickness of compression flange to web ratio (T/tw) = 1.67
Clear depth of web to thickness ratio (d/tw) = 1450/12 = 120.8
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 2725.5 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 161.0 N/mm2
Permissible bending stress 0.62 fy = 155.0 N/mm2
3.1 Analysis of end cross girder during jacked up condition
Position of cable supports below the cross girders along the main girder are given in Fig 1.
Fig. 1 Position of cable supports
Jacking force = DL + SIDL reaction on girder = 1147.2 kN
Number of jacks provided to lift girder = 2
Allow 15% for non equal jacking loads = 1319.3 kN
Maximum bending moment = 923.5 kNm
Calculated bending stress = 923.5 x 0.745 / (0.012 x 1000) = 57.3 N/mm2
Calculated shear stress = 1319.3 x 1000 / (1000 x 12) = 82.5 N/mm2
Equivalent stress = sqrt (57.22 + 3 x 82.5
3) = 153.9 (< 155) N/mm
2
Hence OK.
3.2 Connection between main girder and end cross girder
Nominal diameter of bolt = 20.0 mm
Nominal diameter of bolt hole = 21.5 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Say = 65.0 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20 = 50.0 mm
Maximum pitch for 20 mm dia bolt = Min of 12 x thickness of thinner plate or 200 mm
= 12 x 12 or 200 mm = 144 mm
Number of shear plane = 2.0
Shear capacity of 20 mm bolt in double shear = 101.5 kN
Bearing capacity = 64.5 kN
Strength of each bolt, R = 64.5 kN
No. of bolts required on each side of splice, n = 20.5
No. of rows, m = 3
Provide no. of bolts per row = 21
Pitch required = (1310-210)/(21-1) = 55 mm
34
Check
∑x2 = 2x25x65
2 = 211250 mm
2
∑y2 = 2x3x(55
2+110
2+165
2+220
2+275
2+330
2+385
2+440
2+495
2+550
2+605
2+660
2) = 11797500 mm
2
∑r2 = 211250+ 7865000 = 12008750 mm
2
r = sqrt (652+660
2) = 663.2 mm
Force on the extreme bolt (Fm) = 923.5x103 x 663.2/12008750 = 51.0 kN
Force on each bolt due to shear (Fa) = 1319.3 / (25x3) = 17.6 kN
Angle between Fm and Fa, cos θ = 65/660 = 0.0985
Resultant force Fr = sqrt (512+17.6
2+2x51x17.6x0.0985) = 55.5 kN
Since Fr is less than strength of each bolt, R (64.5 kN), OK
3.3 Welds at junction between web and top flange end cross girder
Horizontal shear at junction of web and top flange, H = V x A x y / I
Maximum shear in girder = 1319.3 kN
Cross sectional area of top flange (A) = 400 x 20 = 0.008 m2
Moment of inertia about major axis (I) = 0.0117 m4
CG of flange plate from top of girder = 0.745 m
CG of flange plate from CG of girder (Y) = 0.745 – 0.01 = 0.735 m
Horizontal shear force (H) = 1319.3 x 0.008 x 0.735 / 0.0117 = 663.0 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 331.5 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
3.4 Welds at junction between web and bottom flange of end cross girder
Maximum shear in girder = 1319.3 kN
Cross sectional area of top flange (A) = 400 x 20 = 0.008 m2
Moment of inertia about major axis (I) = 0.0117 m4
CG of flange plate from top of girder = 0.745 m
CG of flange plate from CG of girder (Y) = 0.745 – 0.01 = 0.735 m
Horizontal shear force (H) = 1319.3 x 0.008 x 0.735 / 0.0117 = 663.0 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 331.5 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
4.0 Design of intermediate cross girder-1
Permissible elastic critical stresses are calculated as per Clause no. 508.6.2 of IRC:24-2001.
Cross sectional area of both flanges at the maximum BM zone (A1) = 16000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 16000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 1.0
Coefficient associate with ψ (k1) = 1.0
35
Moment of inertia of both flanges at the maximum BM zone (I1) = 20 x 4003 / (12) = 10.67 x 10
7 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 20x4003/12+20x400
3/12 = 21.3 x10
7 mm
4
Ratio of total Moment of inertia of both flanges (β) = I1/I2 = 0.5
Coefficient associate with β (k2) = 0.0
Effective length of compression flange (Leff) = 2500 mm
Moment of inertia about minor axis (Iy) = I2 = 21.3 x 107 mm
4
Cross sectional area of girder (A) = 400 x 20 + 400 x 20 + 12 x 960 = 29800 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 84.5 mm
Slenderness ratio, λ = Leff / ry = 29.6
Overall depth of beam (D) = 1190 mm
Mean thickness of compression flange (T) = 20 mm
Ratio D/T = 59.5
Coefficient Y = 26.5 x 105 / λ
2 = 3024.6
Coefficient X = Y [1 + (LeffT/ryD)2 / 20]
1/2 = 3043.2
Lesser distance of extreme fibre from neutral axis (c1) = 595
Greater distance of extreme fibre from neutral axis (c2) = 595
Thickness of compression flange to web ratio (T/tw) = 1.67
Clear depth of web to thickness ratio (d/tw) = 1190/12 = 99.2
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 3024.6 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 161.5 N/mm2
Permissible bending stress 0.62 fy = 155.0 N/mm2
Prestressing force = 287 kN
Maximum bending moment = 180 kNm
Calculated bending stress = 180 x 0.595 / (0.007 x 1000) = 15.3 N/mm2
Calculated shear stress = 287 x 1000 / (1000 x 12) = 24.0 N/mm2
Equivalent stress = sqrt (15.32 + 3 x 24.0
2) = 44.0 (< 155) N/mm
2
4.1 Connection between main girder and cross girder-1
Nominal diameter of bolt = 20.0 mm
Nominal diameter of bolt hole = 21.5 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Say = 80.0 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20 = 50.0 mm
Maximum pitch for 20 mm dia bolt = Min of 12 x thickness of thinner plate or 200 mm
= 12 x 12 or 200 mm = 144 mm
Number of shear plane = 2.0
Shear capacity of 20 mm bolt in double shear = 101.5 kN
Bearing capacity = 64.5 kN
Strength of each bolt, R = 64.5 kN
No. of bolts required on each side of splice, n = 5.4
No. of rows, m = 2
Provide no. of bolts per row = 16
Pitch required = (965-115)/(16-1) = 55 mm
Check:
∑x2 = 2x19x80
2 = 243200 mm
2
∑y2 = 2x1x(55
2+110
2+165
2+220
2+275
2+330
2+385
2+440
2+495
2) = 1724250 mm
2
∑r2 = 243200+ 1724250 = 1967450 mm
2
r = sqrt (802+495
2) = 501.4 mm
Force on the extreme bolt (Fm) = 180x103x501.4/1967450 = 45.8 kN
Force on each bolt due to shear (Fa) = 287 / (19x1) = 15.1 kN
Angle between Fm and Fa, cos θ = 80/495 = 0.16
Resultant force Fr = sqrt (45.82+15.1
2+2x45.8x15.1x0.16) = 50.5 kN
Since Fr is less than strength of each bolt, R (64.5 kN), OK
36
4.2 Welds at junction between web and top flange in cross girder-1
Horizontal shear at junction of web and top flange, H = V x A x y / I
Maximum shear in girder = 287.0 kN
Cross sectional area of top flange (A) = 400 x 20 = 0.008 m2
Moment of inertia about major axis (I) = 0.007 m4
CG of flange plate from top of girder = 0.595 m
CG of flange plate from CG of girder (Y) = 0.595 – 0.01 = 0.585 m
Horizontal shear force (H) = 287 x 0.008 x 0.285 / 0.007 = 93.5 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 46.8 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
4.3 Welds at junction between web and bottom flange in cross girder-1
Maximum shear in girder = 287.0 kN
Cross sectional area of top flange (A) = 400 x 20 = 0.008 m2
Moment of inertia about major axis (I) = 0.007 m4
CG of flange plate from top of girder = 0.595 m
CG of flange plate from CG of girder (Y) = 0.595 – 0.01 = 0.585 m
Horizontal shear force (H) = 287 x 0.008 x 0.285 / 0.007 = 93.5 kN/m
Number of weld surfaces available = 2
Horizontal shear per weld surface = 46.8 kN/m
Minimum weld size required = 10.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 103.68 N/mm2
Shear capacity of 10 mm thick continuous weld = 0.7 x 10 x 103.68 = 725.76 kN/m
Since weld capacity exceeds the actual load, size of weld selected is OK.
5.0 Design of intermediate cross girder-2
Permissible elastic critical stresses are calculated as per Clause no. 508.6.2 of IRC:24-2001.
Cross sectional area of both flanges at the maximum BM zone (A1) = 16000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 16000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 1.0
Coefficient associate with ψ (k1) = 1.0
Moment of inertia of both flanges at the maximum BM zone (I1) = 20 x 4003 / (12) = 10.67 x 10
7 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 20 x 4003 / 12 + 20x400
3/12 = 21.3 x 10
9 mm
4
Ratio of total Moment of inertia of both flanges (β) = I1/I2 = 0.5
Coefficient associate with β (k2) = 0.0
Effective length of compression flange (Leff) = 2500 mm
Moment of inertia about minor axis (Iy) = I2 = 21.3 x 107 mm
4
Cross sectional area of girder (A) = 400 x 20 + 400 x 20 + 12 x 1485 = 37600 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 75.3 mm
Slenderness ratio, λ = Leff / ry = 33.2
Overall depth of beam (D) = 1840 mm
Mean thickness of compression flange (T) = 20 mm
Ratio D/T = 92
37
Coefficient Y = 26.5 x 105 / λ
2 = 2768.1
Coefficient X = Y [1 + (LeffT/ryD)2 / 20]
1/2 = 2832.5
Lesser distance of extreme fibre from neutral axis (c1) = 860
Greater distance of extreme fibre from neutral axis (c2) = 860
Thickness of compression flange to web ratio (T/tw) = 1.67
Clear depth of web to thickness ratio (d/tw) = 1190/12 = 124.2
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 2738.2 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 160.1 N/mm2
Permissible bending stress 0.62 fy = 155.0 N/mm2
Prestressing force = 287 kN
Maximum bending moment = 180 kNm
Calculated bending stress = 180 x 0.925 / (0.019 x 1000) = 8.8 N/mm2
Calculated shear stress = 287 x 1000 / (1000 x 12) = 24.0 N/mm2
Equivalent stress = sqrt (8.82 + 3 x 24.0
2) = 42.5 (< 155) N/mm
2
5.1 Connection between main girder and cross girder-2
Since cross girder-1 is critical and it is safe in bolts design. Therefore provide same type and
number of bolts in cross girder-2 with different pitch and spacing as given below:
Edge distance = 90.0 mm
Number of shear plane = 2.0
No. of rows, m = 2
No. of bolts per row = 18
Pitch required = (1485-110)/(18-1) = 75 mm
5.2 Welds at junction between web and flange of cross girder-2
The welding in the cross girder-2 will also be the same as of cross girder-1.
6.0 Design of intermediate cross girder-3
Permissible elastic critical stresses are calculated as per Clause no. 508.6.2 of IRC:24-2001.
Cross sectional area of both flanges at the maximum BM zone (A1) = 16000 mm2
Cross sectional area of both flanges at the least BM zone (A2) = 16000 mm2
Ratio of total area of both flanges (ψ) = A2/A1 = 1.0
Coefficient associate with ψ (k1) = 1.0
Moment of inertia of both flanges at the maximum BM zone (I1) = 10.67 x 107 mm
4
Moment of inertia of both flanges at the least BM zone (I2) = 21.3 x 107 mm
4
Ratio of total Moment of inertia of both flanges (β) = I1/I2 = 0.5
Coefficient associate with β (k2) = 0.0
Effective length of compression flange (Leff) = 2500 mm
Moment of inertia about minor axis (Iy) = I2 = 21.3 x 107 mm
4
Cross sectional area of girder (A) = 400 x 20 + 400 x 20 + 12 x 1640 = 40000 mm2
Radius of gyration about minor axis, ry = (Iy/A)1/2
= 73.0 mm
Slenderness ratio, λ = Leff / ry = 34.2
Overall depth of beam (D) = 2040 mm
Mean thickness of compression flange (T) = 20 mm
Ratio D/T = 102
Coefficient Y = 26.5 x 105 / λ
2 = 2265.7
Coefficient X = Y [1 + (LeffT/ryD)2 / 20]
1/2 = 2294.6
Lesser distance of extreme fibre from neutral axis (c1) = 1020
Greater distance of extreme fibre from neutral axis (c2) = 1020
Thickness of compression flange to web ratio (T/tw) = 1.67
38
Clear depth of web to thickness ratio (d/tw) = 2040/12 = 170
Elastic critical stress (fcb) = k1 (X+k2Y)(c2/c1) = 2294.6 N/mm2
Yield stress of steel (fy) = 250 N/mm2
Permissible bending stress (σbc) = 0.66 x fcb x fy / [(fcb)1.4
+ (fy)1.4
]1/1.4
= 159.9 N/mm2
Permissible bending stress 0.62 fy = 155.0 N/mm2
Prestressing force = 287 kN
Maximum bending moment = 180 kNm
Calculated bending stress = 180 x 1.02 / (0.024 x 1000) = 7.7 N/mm2
Calculated shear stress = 287 x 1000 / (1000 x 12) = 24.0 N/mm2
Equivalent stress = sqrt (7.72 + 3 x 24.0
2) = 42.3 (< 155) N/mm
2
6.1 Connection between main girder and cross girder-3
Since cross girder-1 is critical and it is safe in bolts design. Therefore provide same type and
number of bolts in cross girder-3 with different pitch and spacing as given below:
Edge distance = 100.0 mm
Number of shear plane = 2.0
No. of rows, m = 2
No. of bolts per row = 18
Pitch required = (1660-125)/(18-1) = 85 mm
6.2 Welds at junction between web and flange of cross girder-3
The welding in the cross girder-3 will also be the same as of cross girder-1.
7.0 Design of splice joints
The design of splice plates is done as per Clause no. 512.3.2 of IRC: 24-2001.
7.1 Design of splice joint-1 of web plate
Depth of web plate = 2.00 m
Thickness of web plate = 0.012 m
Moment of inertia of web plate about centre line = 0.012 x 2.03/12
= 0.008 m4
Calculation of bending moment taken by web only
(i) During erection stage (Self weight + Deck slab)
Depth of neutral axis from bottom plate = 0.942 m
Moment of inertia of whole section = 0.036 m4
Design bending moment = 604.4+2469.5
= 3073.9 kNm
Bending moment resisted by web plate = 3073.9x 0.008 / 0.036
= 683.1 kNm
(ii) During permanent loading (SIDL) on composite section
Depth of neutral axis from bottom plate = 1.76 m
Moment of inertia of whole section = 0.091 m4
Design bending moment = 1969.8 kNm
Bending moment resisted by web plate = 1969.8x0.008/0.091 = 175 kNm
(iii) During transient loading (FPLL+LL with impact) on composite section
Depth of neutral axis from bottom plate = 1.76 m
Moment of inertia of whole section = 0.091 m4
Design bending moment = 761.7 + 2806 = 2567.7 kNm
Bending moment resisted by web plate = 2567.7x 0.008 / 0.091
39
= 313.6 kNm
Shear force resisted by web = 848 kNm
Eccentricity of bolt group from splice point = 0.135 m
Hence total moment resisted by web alone due to live load (Mw) = 858.1 kNm
Distance of splice plate extreme fibre from bottom of girder = 0.04 m
Distance of splice plate extreme fibre from top of girder = 0.04 m
Depth of splice plate = 2.0-0.04-0.04-0.01 = 1.910 m
Bending stress at extreme fibre of splice plate:
σ (top) = 68.5+ (-11.1-68.5)/(2.0+0.04+0.04)x0.04 = 67.0N/mm2
σ (bottom) = 68.5+ (-11.1-68.5)/(/(2.0+0.04+0.04)x(1.91+0.04) = -6.1N/mm2
Minimum thickness of splice web plate required
= 858 x 0.008 / 67/ 19202 x 10
8 = 2.8 mm
Thickness of splice plate provided = 12.00 mm
Nominal diameter of bolt = 20.0 mm
Nominal diameter of bolt hole = 21.5 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Say = 60.0 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20 = 50.0 mm
Hence provide pitch = 70.0 mm
Maximum pitch for 20 mm dia bolt = Min of 12 x thickness of thinner plate or 200 mm
= 12 x 12 or 200 mm = 144 mm
Number of shear plane = 2.0
Shear capacity of 20 mm bolt in double shear = 101.5 kN
In bearing web = 64.5 kN
Strength of each bolt, R = 64.5 kN
Distance between extreme bolts = 1.80 m
Assume pitch of bolts, p = 75 mm
No. of rows, m = 3
No. of bolts in each row, n = sqrt (6 x Mw/(m x p x R)) = 20.6
Provide no. of bolts = 25
Pitch required = (1910-80)/(25-1) = 75 mm
Check
∑x2 = 2x25x60
2 = 180000 mm
2
∑y2 = 2x3x(75
2+150
2+225
2+300
2+375
2+450
2+525
2+600
2+675
2+750
2+825
2+900
2)
= 21937500 mm2
∑r2 = 180000 + 21937500 = 22117500 mm
2
r = sqrt (602 +900
2) = 902 mm
Force on the extreme bolt (Fm) = 858x103x902/22117500 = 35 kN
Force on each bolt due to shear (Fa) = 848 / (25x3) = 11.3 kN
Angle between Fm and Fa, cos θ = 60/900 = 0.067
Resultant force Fr =sqrt (352+11.3
2+2x35x11.3x0.067) = 37.5 kN
Since Fr is less than strength of each bolt, R (64.5 kN), OK
7.2 Design of splice joint-2 of web plate
Depth of web plate = 2.00 m
Thickness of web plate = 0.012 m
Moment of inertia of web plate about centre line = 0.012 x 2.03 / 12
= 0.008 m4
Calculation of bending moment taken by web only
(i) During erection stage (Self weight + Deck slab)
Depth of neutral axis from bottom plate = 0.938 m
40
Moment of inertia of whole section = 0.065 m4
Design bending moment = 1560 + 5828 = 7388 kNm
Bending moment resisted by web plate = 7388x 0.008 / 0.065 = 909 kNm
(ii) During permanent loading (SIDL) on composite section
Depth of neutral axis from bottom plate = 1.61 m
Moment of inertia of whole section = 0.137 m4
Design bending moment = 4748 kNm
Bending moment resisted by web plate = 4748 x 0.008 / 0.137 = 277 kNm
(iii) During transient loading (FPLL+LL with impact) on composite section
Depth of neutral axis from bottom plate = 1.61 m
Moment of inertia of whole section = 0.137 m4
Design bending moment = 1832 + 5847 = 6533 kNm
Bending moment resisted by web plate = 6533 x 0.008 / 0.137 = 448 kNm
Shear force resisted by web = 390 kNm
Eccentricity of bolt group from splice point = 0.135 m
Hence total moment resisted by web alone (Mw) = 909 +277 = 1186 kNm
Distance of splice plate extreme fibre from bottom of girder = 0.04 m
Distance of splice plate extreme fibre from top of girder = 0.04 m
Depth of splice plate = 2.0-0.04-0.04-0.01 = 1.91 m
Bending stress at extreme fibre of splice plate:
σ (top) = 90.2+ (-26.4-90.2)/(2.0+0.04+0.04)x0.04 = 88.5N/mm2
σ (bottom) = 90.2+ (-26.4-90.2)/(2.0+0.04+0.04)x(1.91+0.04) = -8.6 N/mm2
Minimum thickness of splice web plate required = 1186x 0.008 / 88.5/ 19202 x 10
8 = 2.9 mm
Thickness of splice plate provided = 12.00 mm
Nominal diameter of bolt = 20.0 mm
Nominal diameter of bolt hole = 21.5 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Say = 60.0 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20 = 50.0 mm
Hence provide pitch = 70.0 mm
Maximum pitch for 20 mm dia bolt = Min of 12 x thickness of thinner plate or 200 mm = 12 x 12 or 200 mm
= 144 mm
Number of shear plane = 2.0
Shear capacity of 20 mm bolt in double shear = 101.5 kN
In bearing web = 64.5 kN
Strength of each bolt, R = 64.5 kN
Distance between extreme bolts = 1.80 m
Assume pitch of bolts, p = 75 mm
No. of rows, m = 3
No. of bolts, n = sqrt (6 x Mw/(m x p x R)) = 24.25
Provide no. of bolts = 25
Pitch required = (1910-80)/(25-1) = 75 mm
Check
∑x2 = 2x25x60
2 = 180000 mm
2
∑y2 = 2x3x(75
2+150
2+225
2+300
2+375
2+450
2+525
2+600
2+675
2+750
2+825
2+900
2) = 21937500 mm
2
∑r2 = 180000 + 21937500 = 22117500 mm
2
r = sqrt (602+900
2) = 902 mm
Force on the extreme bolt (Fm) = 1186x103x902/22127500 = 48.3 kN
Force on each bolt due to shear (Fa) = 390/ (25x3) = 5.2 kN
Angle between Fm and Fa, cos θ = 60/900 = 0.067
Resultant force Fr =sqrt (48.32+5.2
2+2x48.3x5.2x0.067) = 48.9 kN
Since Fr is less than strength of each bolt, R (64.5 kN), OK
41
7.3 Design of splice joint-1 of top flange plate
Cross sectional area of top plate = 0.60 x 0.020 = 0.012 m2
Splice cover plate required = 1.05 x 0.012 = 0.0126 m2
Maximum compressive stress at top = 93.1 N/mm2
Compressive force in top flange plate = 93100 x 0.012 = 1117.2 kN
Design force on each side of the splice shall be greater of
(i) 1.1 x computed force at the splice point = 1.1 x 117.2 = 1229 kN
(ii) 0.8 x maximum force in the flange plate = 0.8 x 148.8 x 0.012 x 1000 = 1428.5 kN
Hence design force on each side of the plate = 1428.5 kN
Splice cover plate required from force consideration = 0.8 x 0.012 = 0.0096 m2
Number of splice plate required for top flange = 2
Width of top splice plate of top flange = 0.600 m
Width of bottom splice plate of top flange = 0.280 m
Thickness of splice plate of top flange required = 0.0096 / (0.60 + 0.28) = 0.011 m
Provide thickness of splice plate of top flange = 0.020 m
Nominal diameter of site snap headed bolt = 20.00 mm
Nominal diameter of bolt hole = 21.50 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Provide edge distance for 20 mm dia bolt = 40.00 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20.0 = 50.00 mm
Maximum pitch for 20 mm dia bolt = minimum of 200 or 12 x 30 = 200 mm
Number of shear plane = 2
Shear capacity of 20 mm dia bolt in double shear = 101.50 kN
Number of bolt required on each side of splice = 1428.5/101.5 = 14.1
Number of bolts arranged per row = 6
Number of rows required = 6
Pitch required in transverse direction = (280-40-40)/2 = 100mm
7.4 Design of splice joint-1 of bottom flange plate
Cross sectional area of top plate = 0.80 x 0.020 = 0.016 m2
Splice cover plate required = 1.05 x 0.032 = 0.0168 m2
Maximum compressive stress at bottom = 79.9 N/mm2
Compressive force in bottom flange plate = 79900 x 0.016 = 1278 kN
Design force on each side of the splice shall be greater of
(i) 1.1 x computed force at the splice point = 1.1 x 1278 = 1406 kN
(ii) 0.8 x maximum force in the flange plate = 0.8 x 148.8 x 0.016 x 1000 = 1905 kN
Hence design force on each side of the plate = 1905 kN
Splice cover plate required from force consideration = 0.8 x 0.016 = 0.0128 m2
Number of splice plate required for bottom flange = 2
Width of bottom splice plate of bottom flange = 0.800 m
Width of top splice plate of bottom flange = 0.380 m
Thickness of splice plate of bottom flange required = 0.0128 / (0.80 + 0.38) = 0.011 m
Provide thickness of splice plate of bottom flange = 0.020 m
Nominal diameter of site snap headed bolt = 20.00 mm
Nominal diameter of bolt hole = 21.50 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Provide edge distance for 20 mm dia bolt = 40.00 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20.0 = 50.00 mm
Number of shear plane = 2
Shear capacity of 20 mm dia bolt in double shear = 101.50 kN
Number of bolt required on each side of splice = 1905/101.5 = 18.8
Number of bolts arranged per row = 6
Number of rows required = 6
Length of splice plate required = 2(40+0+60x6) = 880mm
42
7.5 Design of splice joint-2 of top flange plate
Cross sectional area of top plate = 0.060 x 0.040 = 0.024 m2
Splice cover plate required = 1.05 x 0.024 = 0.0252 m2
Maximum compressive stress at top = 129 N/mm2
Compressive force in top flange plate = 129000 x 0.024 = 3096 kN
Design force on each side of the splice shall be greater of
(i) 1.1 x computed force at the splice point = 1.1 x 3096 = 3406 kN
(ii) 0.8 x maximum force in the flange plate = 0.8 x 148.8 x 0.024 x 1000 = 2857 kN
Hence design force on each side of the plate = 3406 kN
Splice cover plate required from force consideration = 0.8 x 0.024 = 0.0192 m2
Number of splice plate required for top flange = 2
Width of top splice plate of top flange = 0.600 m
Width of bottom splice plate of top flange = 0.280 m
Thickness of splice plate of top flange required = 0.0192 / (0.60 + 0.28) = 0.022 m
Provide thickness of splice plate of top flange = 0.030 m
Nominal diameter of site snap headed bolt = 20.00 mm
Nominal diameter of bolt hole = 21.50 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Provide edge distance for 20 mm dia bolt = 40.00 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20.0 = 50.00 mm
Maximum pitch for 20 mm dia bolt = minimum of 200 or 12 x 30 = 200 mm
Number of shear plane = 2
Shear capacity of 20 mm dia bolt in double shear = 101.50 kN
Number of bolt required on each side of splice = 3406/101.5 = 33.0
Number of bolts arranged per row = 7
Number of rows required = 6
7.6 Design of splice joint-2 of bottom flange plate
Cross sectional area of top plate = 0.080 x 0.040 = 0.032 m2
Splice cover plate required = 1.05 x 0.032 = 0.0336 m2
Maximum compressive stress at bottom = 106 N/mm2
Compressive force in bottom flange plate = 106000 x 0.032 = 3312 kN
Design force on each side of the splice shall be greater of
(i) 1.1 x computed force at the splice point = 1.1 x3312 = 3644 kN
(ii) 0.8 x maximum force in the flange plate = 0.8 x 148.8 x 0.032 x 1000 = 3809 kN
Hence design force on each side of the plate = 3809 kN
Splice cover plate required from force consideration = 0.8 x 0.032 = 0.0256 m2
Number of splice plate required for bottom flange = 2
Width of bottom splice plate of bottom flange = 0.800 m
Width of top splice plate of bottom flange = 0.380 m
Thickness of splice plate of bottom flange required = 0.0256 / (0.80 + 0.38) = 0.022 m
Provide thickness of splice plate of bottom flange = 0.030 m
Nominal diameter of site snap headed bolt = 20.00 mm
Nominal diameter of bolt hole = 21.50 mm
Minimum edge distance for 20 mm dia bolt = 1.75 x 21.5 = 37.63 mm
Provide edge distance for 20 mm dia bolt = 40.00 mm
Minimum pitch for 20 mm dia bolt = 2.5 x 20.0 = 50.00 mm
Maximum pitch for 20 mm dia bolt = minimum of 200 or 12 x 30 = 200 mm
Number of shear plane = 2
Shear capacity of 20 mm dia bolt in double shear = 101.50 kN
Number of bolt required on each side of splice = 3809/101.5 = 37.5
Number of bolts arranged per row = 7
Number of rows required = 6
43
8.0 Design of intermediate transverse stiffeners
Design of intermediate transverse stiffeners is done as per Clause no. 508.11.2 of IRC: 24-2001.
Clear depth of web between root filled (d3) = 2.0 m
Web thickness provided (tw) = 0.012 m
Aspect ratio (d3/tw) = 166.67
Since aspect ratio is greater than 85 but less than 200, only Transverse Stiffeners is required.
Clear distance between flanges / longitudinal stiffener (d’) = 2.0 m
Maximum permitted spacing of transverse stiffener=Min of 1.5x2.0 or 180x0.012= 2.16m
Minimum permitted spacing of transverse stiffener = 0.33 x 2.0 = 0.66 m
Effective span of girder = 47.8 m
Spacing of transverse stiffener provided near mid span (s) = 1.74 m
Number of stiffener = 26
Clear distance between flange (d2) = 2.0 m
Smaller clear dimension (c) = Min of d2 and s = 1.74 m
Greater clear dimension (d) = Max of d2 and s = 2.0 m
Minimum permitted thickness of web (tmin), for d3/tw = 166.7 < 200
= Maximum of c/180 or d/270 or d2/250
= Maximum of 1.74/180 or 2.0/270 or 2.0/250 = 0.01 m OK
Maximum spacing of transverse stiffener for thickness (S) = 270tmin = 2.60 m
Minimum moment of inertia required (Imin=1.5 x d’3 x tmin
3/S
2) = 1.57 x 10
-6 m
4
Thickness of intermediate stiffeners provided (t) = 0.012 m
Effective outstand of stiffener (12 x t) = 0.144 m
Minimum flange width available (2.60 – 2.0) = 0.60 m
Available width for stiffener on each side of web = (0.60-0.012) / 2 = 0.294 m
Consider effective width of outstand (h) = Min of 0.294 and 0.144 = 0.144 m
Ixx of intermediate stiffener about CL of web
= 2 x 0.012 x 0.1443 / 12 + 2 x 0.012 x 0.144 x (0.144/2 + 0.012/2)
2 = 2.70 x 10
-5 m
4
Since actual moment of inertia exceeds the minimum value, section of transverse stiffeners selected are OK.
8.1 Welds at junction between transverse stiffeners and web
Design of welds at junction between transverse stiffeners and web is done as per Clause no.
512.2.2.2 of IRC: 24-2001.
Design shear force for transverse stiffener = 125 x t2 / h = 125.0 kN/m
Depth of stiffener = 2.0 – 2 x 0.05 = 1.90 m
Total shear force = 125 x 1.9 = 237.5 kN
Number of weld surface available = 4
Minimum weld size required = 4.00 mm
Weld size provided = 5.00 mm
Maximum leg length of fillet weld = size – 1 = 4.00 mm
Effective length of weld should be greater than = 4 x (2.0–2 x 0.05) = 7.60 m
Permissible shear capacity of fillet weld in shop = 108 N/mm2
Shear capacity of 5 mm thick continuous weld = 5 x 108 / 1.414 = 381.9 kN/m
Strength of 7.60 m long 5 mm thick continuous weld = 381.9 x 7.6 = 2902.4 kN
Since weld capacity exceeds the actual load, size of weld selected is OK.
9.0 Design of bearing stiffeners
Design of bearing stiffeners is done as per Clause no. 508.11.1 of IRC: 24-2001.
Thickness of bearing stiffener (tb) = 0.025 m
44
Permissible outstand of stiffener (12tb) = 0.300 m
Minimum flange width available = 0.60 m
Available width for stiffener on each side of web = 0.294 m
Effective width of outstand = Min of 0.300 and 0.294 = 0.294 m
Effective length of web to act as stiffener on either side (leff) = 16tw = 0.192 m
Minimum available length of web on either side = 0.750 m
Total effective length of web = (Min of 0.75 and 0.192) + 0.192 = 0.384 m
9.1 Check as strut
Length of stiffener (Lb) = Length of web = 2.0 m
Effective length of stiffener (Leff) = 0.7 Lb = 1.4 m
Total reaction on bearing during service (R) = 1887 kN
Effective area (Aeff) = 0.384 x 0.012 + 2 x 0.30 x 0.02 = 0.0166 m2
Effective moment of inertia about major XX axis (Ix)
= (0.384 - 0.025) x 0.0123/12 + 0.025 x (0.300 x 2 +0.012)
3/12 = 4.24E-04 m
4
Effective moment of inertia about minor YY axis (Iy)
= (0.300 x 2) x 0.0253/12 + 0.012 x (0.384
3/12) = 5.74E-05 m
4
Effective radius of gyration about YY axis (ry) = sqrt (Iy/Aeff) = 0.059 m
Slenderness ratio (λ = Leff/ry) = 23.73
Elastic critical stress in compression (fcc = E x (π/ λ)2) = 211000 x (3.14/23.73)
2 = 3694.4 N/mm
2
Yield stress of steel (fy) = 250 N/mm2
Permissible axial compressive stress (σac) = 0.6 x fcc x fy / [fcc1.4
+ fy1.4
] (1/1.4)
= 147.58 N/mm2
Calculated compressive stress (σa = R/Aeff) = 113.7N/mm2
Since axial compressive stress is below the permissible value, section of bearing stiffeners selected is OK.
9.2 Check for bearing stress
Permissible notch in stiffener at junction of web and flange to clear weld (5tw) = 0.060 m
Notch provided at junction = 0.050 m
Area of outstanding leg of stiffener in contact with flange = 2 x (0.3 – 0.05) x 0.025 = 0.0125 m
Permissible bearing stress (0.8 x fy) = 200.00 N/mm2
Bearing stress in stiffener = 1887/ (0.0125 x 1000) = 150.9 N/mm2
Since bearing stress is below the permissible value, section of bearing stiffeners selected is OK.
9.3 Welds at junction between bearing stiffeners and web
Design of welds at junction between bearing stiffeners and web is done as per Clause no. 512.2.2.2 of IRC:
24-2001.
Design shear force for transverse stiffener = 125 x t2 / h = 125.0 kN/m
Depth of stiffener = 2.0 – 2 x 0.05 = 1.90 m
Total shear force = 125 x 1.9 = 237.5 kN
Number of weld surface available = 4
Length of weld available = 4 x (2.0 – 2 x 0.05) = 7.6 m
Minimum weld size required = 8.00 mm
Weld size provided = 10.00 mm
Permissible shear capacity of fillet weld in shop = 108 N/mm2
Shear capacity of 10 mm thick continuous weld = 10 x 108 / 1.414 = 763.8 kN/m
Strength of 7.60 m long 10 mm thick continuous weld = 763.8 x 7.6 = 5804.8 kN
Since weld capacity exceeds the actual load, size of weld selected is OK.
6250
80
SECTION AT B-B
NOTES:-
7. ANGLE OF INTERNAL FRICTION OF BACK FILL MATERIAL SHALL NOT BE LESS THAN 35°
1. ALL THE DIMENSIONS ARE IN mm AND ALL LEVELS IN METERS UNLESS
9. ALL DIMENSIONS AND LEVELS SHOULD BE VERIFIED & RECONCILED BEFORE EXECUTION.
6. HIGH YIELD STRENGTH DEFORMED TMT BAR OF GRADE Fe-500 CONFORMING TO
11. WEEP HOLES SHALL BE OF 75 DIA PVC PIPES STAGGERED @ 1000 C/C BOTH
HORIZONTALLY & VERTICALLY IN RETAINING WALL & ABUTMENT.
10. BACK FILL SHOULD BE AS PER CLAUSE 7.5 OF IRS BRIDGE SUB-STRUCTURE AND
4. CONCRETE GRADE:-
IS: 1786-1986 SHALL BE USED AS REINFORCEMENT.
II) SUBSTRUCTURE , FOOTING & RETURN WALL = M 30
FOUNDATION CODE.
OTHERWISE SPECIFIED.
16. GRADED AGGREGATE OF NOMINAL SIZE 20 mm SHALL BE USED AS PER IS : 383.
NOT MORE THAN 50% BARS SHOULD BE LAPPED AT ANY CROSS SECTION.
14. LAP LENGTHS SHOULD BE 45 D WHERE D = DIA. OF BARS. LAP JOINT SHOULD BE STAGGERED.
15. IF THE BAR DIA, IS MORE THAN 32 mm DIA, OF BAR, LAP LENGTHS SHOUL BE GIVEN AS PER
CLAUSE NO. 15.9.6.6 OF IRS CONCRETE BRIDGE CODE.
I) SUPERSTUCTURE & BED BLOCK = M45
8. DIMENSION GIVEN IN THE DRAWING MUST BE CHECKED AT SITE BEFORE START OF THE WORK
FOR FEASIBILITY.
5. ALL RCC WORK SHALL CONFORM TO RELEVANT IRC CODE & MOST SPECIFICATION.
III) RETAINING WALL = M 30
12. TYPE OF FOUNDATION (OPEN/DEEP) SHALL BE DECIDED AFTER THE GEOTECHNICAL
INVESTIGATION AT NEW LOCATION, THE LOCATION HAS BEEN CHANGED DUE TO ONE
ADDITIONAL TRACK UNDER STAGE-III WORK.
SCALE 1 : 2
1173
0
1173
0
2350
1000
DESIGNEDBY:
TITLE: TYPICAL GENERAL ARRANGEMENT DRAWING
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO.DATE:1 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
GENERAL ARRANGEMENT DRAWING
19T15 Prestressing Tendon
AB
B
C
CSplice Joint-1 Splice Joint-2
D
DBearing End Cross Girder
Cross Girder-1 Cross Girder-2
Cross Girder-3
DESIGNEDBY:
TITLE: LONGITUDINAL SECTION & TENDON PROFILE
Dr. Pramod Kumar Singh Professor Department of Civil Engineering IIT (BHU), Varanasi
Harshad BirajdarResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO. DATE:2 OF 9 1 /04 / 2013
NOTES
1. ALL DIMENSIONS ARE IN MILLIMETERS AND LEVELS ARE IN METERS UNLESSOTHERWISE SPECIFIED.
2. DIMENSIONS ARE NOT TO BE SCALED, ONLY WRITTEN DIMENSIONS ARE TOBE FOLLOWED.
3. GRADE OF CONCRETE FOR DECK SLAB SHALL BE M454. ALL STRUCTURAL STEEL ROLLED SECTIONS & PLATES SHALL BE OF Fe410
GRADE-B STEEL (Fy = 250MPa) CONFORMING TO IS:2062-1999.5. ALL WELDING SHALL CONFORM TO IS:816-1969 AND IS:1323-1982.6. MATERIAL AND FABRICATION FOR ALL HIGH STRENGTH FRICTION GRIP
BOLTS, NUTS AND WASHERS SHALL CONFORM TO IS:4000:1992, IS:3757:1985,IS:6623-1985 & IS:6649-1985.
7. SURFACE PREPARATION FOR CONNECTIONS USING HSFG BOLT MUSTCONFORM TO IS:4000-1992 TO ATTAIN A SLIP FACTOR OF 0.30.
8. ALL HSFG BOLTS, NUTS AND WASHERS ARE OF PROPERTY CLASS 8.8 HOT DIPGALVANIZED CONFORMING TO IS:3757-1985.
9. FABRICATION AND STRUCTURAL STEEL WORKS SHALL CONFORM TOIRC:24-2001 (SECTION-V), IS:7205:1974 & IS:7215-1974.
10. DIAMETER OF HOLES FOR HIGH STRENGTH FRICTION GRIP BOLTS SHALL BE1.5mm LARGER THAN NOMINAL DIAMETER OF BOLT UP TO 25mm BOLTDIAMETER.
11. ALL HOLES FOR HSFG BOLTS SHALL BE DRILLED.12. FLEXIBLE SHEAR CONNECTORS IN THE FORM OF STUDS SHALL HAVE A
CHARACTERISTIC YIELD STRENGTH OF 385MPa , MINIMUM ELONGATION OF18% AND CHARACTERISTIC TENSILE STRENGTH OF 495MPa CONFORMING TOCl. 606.4.1.1 OF IRC:22-2008.
13.SPECIAL PRECAUTIONS SHALL BE TAKEN TO ENSURE SOUNDNESS OF WELDSIN THE BUILT UP GIRDERS HAVING THICK PLATES.
14.THE WELDS ARE TO BE CONTINUOUS UNLESS SHOWN OTHERWISE.15. ALL INTERMEDIATE STIFFENERS SHALL BE WELDED ONLY TO THE WEB AND
NOT TO THE FLANGE.16.END BEARING STIFFENERS SHALL BE CONNECTED WITH WEB BY 10mm
FILLET WELD ALL AROUND.17.ONE END PRESTRESSING SHALL BE DONE.18.878.7N/mm^2 PRESTRESS SHALL BE APPLIED TO 17 STRANDS OF 14 No. 19T15
CABLES AFTER GIRDER LAUNCHING AND CASTING AND HARDENING OFDECK SLAB, LEAVING 2 STRANDS IN EACH CABLE AS EMERGENCYSTRANDS.
HALF LONGITUDINAL SECTIONCL of symmetry
Point of Curtailment
400
20
1360
12
400
20
12
400
20
12
400
20
12
End Cross Girder Cross Girder-1 Cross Girder-2 Cross Girder-3
12
Stiffener Plate
1740
10mmcontinuousweld
1000
960
1485
1485 16
60
1360
A5150 12500 6350
7900 8000 8000
960
Tube-2 Tube-3
Tube-1
Tube-1 Tube-2 Tube-3
101.6 mmouter dia.
168.3mmouter dia.
127mmouter dia.
X
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
22540 40
20
4.54.53.6
Details at X
Y Z
22540 40
20
Details at Y12
716
8.3
127
22540 40
20
1660
168.
3
168.
3
Details at Z
7575 75
101.
6
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti Assistant Professor Department of Civil Engineering IIT (BHU), Varanasi
Deck SlabHaunch 22
010
0
TITLE: DETAILS AT SECTION A-A & B-B
SECTION A-A
1000
SECTION B-B
80mm Wearing Coat
7500
25 M20 BOLT @ 55c/c
12mm thick
Stiffener
10 mm weld
1000
1400
2300
1360
960
30Ø @ 150mm
200 200
200
30Ø @ 125mm
STUD DETAILS FOR
MAIN GIRDER
STUD DETAILS FOR
CROSS GIRDER
(SCALE 1:4) (SCALE 1:4)
NOTES
1. ALL DIMENSIONS ARE IN MILLIMETERS ANDLEVELS ARE IN METERS UNLESS OTHERWISESPECIFIED.
2. DIMENSIONS ARE NOT TO BE SCALED, ONLYWRITTEN DIMENSIONS ARE TO BE FOLLOWED.
3. GRADE OF CONCRETE FOR DECK SLAB SHALL BE
M45
4. FOR LIFTING OF SUPERSTRUCTURE 10 no. FLAT
JACKS SHALL BE USED.
5. THE LOCATION OF JACKS FOR LIFTING UP THE
SUPERSTRUCTURE TO REPLACE BEARING ETC. IS
SHOWN THUS .THESE SHOULD BE DISTINCTLY
ETCHED ON THE END CROSS GIRDER AND PIER
CAPS.
6. THE CABLES SHALL BE ENCASED IN STEEL TUBES
ACTING AS STRUTS ALSO, AND BE PROTECTED
FROM EXTERNAL ENVIRONMENT.
Jacking location
20mm dia
60 no. bolts
ISA150x150x12 stiffener
at jacking location
DETAILS OF END CROSS GIRDER AND CROSS GIRDER 1
Bearing plate
2250
2250
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO.DATE:3 OF 9 1 /04/ 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
575
220
200
200 75
40
40
225
A
DETAILS AT 'A'
(SCALE 1:8)
40mm thick plate
75Ø roller
101.6Ø, 3.6 thick
steel tube
16mm weld
19T15 prestressing
tendon
10 mm continuous weld
to connect bearing stiffener
to web of main longitudinal girder
DETAILS AT SECTION A-A & B-B
SECTION C-C
10 mm weld
1485
SECTION D-D
12mm thick
Stiffener
10 mm weld
1660
2500 2500 2500 2500
220
12mm thick
Stiffener
TITLE: CROSS-GIRDER DETAILS (SECTIONS C-C & D-D)
2500 2500 2500 2500
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO. DATE:4 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
220
NOTES
1. ALL DIMENSIONS ARE IN MILLIMETERS ANDLEVELS ARE IN METERS UNLESS OTHERWISESPECIFIED.
2. DIMENSIONS ARE NOT TO BE SCALED, ONLYWRITTEN DIMENSIONS ARE TO BE FOLLOWED.
3. GRADE OF CONCRETE FOR DECK SLAB SHALL BE
M45
4. FOR LIFTING OF SUPERSTRUCTURE 10 no. FLAT
JACKS SHALL BE USED.
5. THE LOCATION OF JACKS FOR LIFTING UP THE
SUPERSTRUCTURE TO REPLACE BEARING ETC. IS
SHOWN THUS .THESE SHOULD BE DISTINCTLY
ETCHED ON THE END CROSS GIRDER AND PIER
CAPS.
6. THE CABLES SHALL BE ENCASED IN STEEL TUBES
ACTING AS STRUTS ALSO, AND BE PROTECTED
FROM EXTERNAL ENVIRONMENT.
DETAILS OFCROSS-GIRDER (SECTIONS C-C & D-D)
16T @125mm c/c
12T @125mm c/c
16T @125mm c/c
12T @250mm c/c
16T @150mm c/c12T @ 150mm c/c
REINFORCEMENT DETAILS OF DECK SLAB
REINFORCEMENT DETAILS OF END ANCHORAGE
TITLE: DECK SLAB REINFORCEMENT DETAILS
12T @ 150mm c/c
16T @ 125mm c/c
8T@150 C/C MESH
NOTES1. ALL DIMENSIONS ARE IN MILLIMETERS.2. DIMENSIONS ARE NOT TO BE SCALED, ONLY WRITTEN DIMENSIONS ARE TO BE FOLLOWED.3. GRADE OF CONCRETE FOR DECK SLAB SHALL BE M45
4. GRADE OF STEEL FOR GIRDERS IS Fe 410
5. GRADE OF STEEL FOR REINFORCING BARS IS Fe500.
19T15 cable
650
900
220
1000
Epoxy mortor
Sheathing
REINFORCEMENT DETAILS AT TOP
REINFORCEMENT DETAILS AT BOTTOM
16T @250mm c/c
12T @125mm c/c
11999
16T@250 C/C
16T@250 C/C
12T @ 250 C/C
12T @ 250 C/C
1500
7500
1500
12T @ 125 C/C
47800
16T@125 C/C
1500
7500
1500
12T @ 125 C/C
47800
Cantilever
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO. DATE:5 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
DECK SLAB REINFORCEMENT DETAILS
NOTES1. ALL DIMENSIONS ARE IN MILLIMETERS.2. ONLY WRITTEN DIMENSIONS ARE TO BE FOLLOWED.3. ALL BOLTS ARE TO BE HSFG OF GRADE 10.9 & M20
CONFORMING TO IS :4000 UNLESS OTHERWISE STATED4. ALL BOLTS ARE OF 20mm DIAMETER.
40 60 6060 60 60 40 40 60 60 60 60
60 40
4060 60 60 60
60 60 4060 60 60 60 60
60 40
20
20
20
1910
2040
40 100100
120 100 100 40
40 150 150120
150 15040
12
12
12
60 70 70 90 607070
75
55
75
55
55
TRANSVERSE SECTIONLONGITUDINAL SECTION
20Ø BOLTS
20Ø BOLTS
40
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
55
DETAILS OF WEB SPLICES FOR SPLICE JOINT 1
TITLE: DETAILS OF WEB SPLICES FOR SPLICE JOINTS 1 & 2
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO.DATE:6 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
4060 60 60 60
60 60 4060 60 60 60 60
60 40
30
40
30
2000
1940
40 100100
120 100 100 40
40 150 150120
150 15040
30
40
30
12
12
12
60 70 70 90 607070
75
55
75
55
55
TRANSVERSE SECTIONLONGITUDINAL SECTION
20Ø BOLTS
20Ø BOLTS
40
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
55
DETAILS OF WEB SPLICES FOR SPLICE JOINT 2
20
20
20
4060 60 60 60
60 60 4060 60 60 60 60
60 4040
DETAILS OF WEB SPLICES FOR SPLICE JOINTS 1 & 2
40 100 60
60
60
60
60
60
60
60
60
40
40
60
60
60
60
60
60
60
40
40 100 100 40
DETAILS OF TOP FLANGE SPLICE JOINT 1
AT TOP
600
280
76
0
70
88
0
AT BOTTOM
DETAILS OF BOTTOM FLANGE SPLICE JOINT 1
AT BOTTOM
AT TOP
100 40
NOTES1. ALL DIMENSSIONS ARE IN MILLIMETRES AND
LEVELS ARE IN METERS UNLESS OTHERWISESPECIFIED.
2. ONLY WRITTEN DIMENSSIONS ARE TO BEFOLLOWED.
3. ALL BOLTS ARE TO BE HSFG OF GRADE 10.9 &M20 CONFORMING TO IS :4000 UNLESSOTHERWISE STATED
4. ALL BOLTS ARE 20mm IN DIAMETER
60
60
60
60
60
40
4010060 100
40
40
4010010040
45
40 150 150
60 60150 150 40
88
0
40 150 150
40 40150 150 40
40
40
76
0
800
70
70
70
70
45
45
70
45
70
70
70
70
45
70
45
70
70
70
70
45
45
70
45
70
70
70
70
45
TITLE: DETAILS OF FLANGE SPLICES FOR SPLICE JOINT 1
20mm thick plate
20mm thick plate
20mm thick plate
20mm thick plate
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO.DATE:7 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
280
40 100 60
60
60
60
60
60
60
60
60
40
40
60
60
60
60
60
60
60
40
40 100 100 40
DETAILS OF TOP FLANGE SPLICE JOINT 2
AT TOP
600
280
88
0
60
60
60
60
60
60
40
40
60
60
60
60
60
60
88
0
AT BOTTOM
DETAILS OF BOTTOM FLANGE SPLICE JOINT 2
AT BOTTOM
AT TOP
100
40
NOTES1. ALL DIMENSIONS ARE IN MILLIMETERS AND
LEVELS ARE IN METERS UNLESS OTHERWISESPECIFIED.
2. ONLY WRITTEN DIMENSIONS ARE TO BEFOLLOWED.
3. ALL BOLTS ARE TO BE HSFG OF GRADE 10.9 & M20CONFORMING TO IS :4000 UNLESS OTHERWISESTATED
4. ALL BOLTS ARE 20mm IN DIAMETER5. THICKNESS OF SPLICE PLATES SHALL BE 30mm.
60
60
60
60
60
40
4010060 100
40
40
4010010040
40
40
40 150150
60 60150 150 40
60
60
60
60
60
60
40
40
60
60
60
60
60
60
88
0
40
40
40 150150
40 40150 150 40
40
40
TITLE: DETAILS OF FLANGE SPLICES FOR SPLICE JOINT 2
60
60
60
60
DESIGNEDBY:
Dr. Pramod Kumar Singh
Professor
Department of Civil Engineering IIT (BHU), Varanasi
Harshad Birajdar
Research ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO.DATE:8 OF 9 1 /04/ 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti
Assistant Professor
Department of Civil Engineering IIT (BHU), Varanasi
30mm thick plate
30mm thick plate
30mm thick plate
30mm thick plate
280
40
TITLE: ARRANNGEMENT OF MAIN AND CROSS GIRDERS
NOTES
1. ALL DIMENSIONS ARE IN MILLIMETERS AND LEVELS ARE IN METERS UNLESS OTHERWISE SPECIFIED.2. DIMENSIONS ARE NOT TO BE SCALED, ONLY WRITTEN DIMENSIONS ARE TO BE FOLLOWED.3. GRADE OF CONCRETE FOR DECK SLAB SHALL BE M45
Jacking Position
10000
2500
2500
2500
2500
1100Cross Girder-1
Studs@150mm
700
700
End Cross Girder
5150 12500
Splice Joint-1 Splice Joint-2
7900.0 8000.0 8000
Cross Girder-2
Cross Girder-3
20 mm Plate upto 10.0 mfrom both ends
40 mm Plate in mid27.8m length
10000 13900
600
Half Plan at Bottom Flange level
Cables
1100
Half Plan at Top Flange level
DESIGNEDBY:
Dr. Pramod Kumar Singh Professor Department of Civil Engineering IIT (BHU), Varanasi
Harshad BirajdarResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
SHEET NO. DATE:9 OF 9 1 /04 / 2013
DEPARTMENT OF CIVIL ENGINEERING, IIT (BHU), VARANASI
Vikash KhatriResearch ScholarDepartment of Civil EngineeringIIT (BHU), Varanasi
Dr. P R Maiti Assistant Professor Department of Civil Engineering IIT (BHU), Varanasi
C
ARRANGEMENT OF LONGITUDINAL AND CROSS GIRDERS
L
Studs@125mm
10000
800.0
top related