Construction of 440 meter Heavy motor vehicle Dobra Chanthi Suspension bridge project over Tehri Dam reservoir in Distt Tehri Garhwal, Uttarakhand, India
7. Project Management & Engineering
Consultancy
Joint Venture of
Yooshin Engineering Corporation, South Korea
&
VKS Infratech Management Pvt. Ltd., New Delhi
Consultancy Contract Amount : ` 10.73 Crore
Contract Period
For Construction Period : 18 Month
For Post Construction Service : 03 month
Revised Estimate Sanctioned for Input upto
3/2018 + 3 Month Post Construction : ` 15.36 Crore
Provision for PMEC upto 06/2020
(3/2020 + 3 Month PostConstruction)
10. Project Start Date - 12.02.2016
Project Completion Date - 11.08.2017
Time extension sanctioned upto 31.12.2018
Proposed Project Completion Date – 31.03.2020
Reasons of Time Extension
Increasing the major scope of Tower Retrofit Work.
Delay to start Catwalk, Haulage & Cable Erection Work
without Tower Retrofit Work.
Stopping external Retrofit Work due to daily strong wind
effect.
Blockage of Dobra side approach road Bridge (Jakh Bridge).
Modification of miscellaneous design & specifications during
construction.
Suspender Socket Slippage at Chanthi Side End, Dismantling
of old Suspender, Fabrication & Testing of New Suspenders at
Site.
11. SPECIAL CHALLENGES OF THIS BRIDGE
Longest span motorable suspension bridge
of India.
The ground over which this bridge is
standing facing a 90 m drawdown and
submergence every year in whole life.
Intact saddle and ropes system.
Suspension bridge without wind & reverse
cable anchorage system, new International
technology.
13. (A) GENERAL
1. Span
a) Main Bridge - 440 m. Suspension Type
b) Left (Chanthi) side Approach
Bridge
- 25 m. Steel Plate Girder
c) Right (Dobra) side Approach
Bridge
- 260 meter R.C.C. T-Beam Bridge (20
Panels of 13 m. each)
2. Dip of Main Cable - 50 m.
3. Clear Road Way Width - 5.50 m.
4. Width of Footh Path - 0.75 m.
5. Longitudinal Slope - 2%
6. Design Speed - 30. Km./Hour
7. Length of Vertical Curve - 80 m.
8. Longitudinal Camber - 4.0 m.
9. Cross Slope - 2%
10. Full width of Bridge - 5.50 m. Carriagway + 2x0.225 m.
Barrier + 2x0.75 m. foot path + 2x0.25
m. Railing = 7.95 m.
11. Loading - 2 Lane, Class 18R at minimum
distance 30 m clear distance 19T
Tracked or 15.5 Tonne wheeled with
maximum Axle Load of 10 Tonne.
14. (B) TOWER
1. Tower Height - 57.10 m.
2. C/C distance of Towers - 15.0 m.
3. No. of Tower Bracing - 5 No.
4. Along the Bridge Slope of outer
face of Tower Leg
- 92.600
5. Across the Bridge Slope of outer
face of the Tower Leg
- 91.200
6. Total Load of each Tower Leg - 1800 Tonne
7. Self Weight of each Tower Leg - 570 Tonne
8. Nut & Bolts - HSFG 10.9 S Grade
(C) ANCHOR BLOCK
1. Size of Dobra Side Anchor Block - 18x20x37 m. R.C.C. M35 filled with
Plum Concrete
2. Size of Chanthi Side Anchor Block - 18x20x24.80 m. R.C.C. M35 filled with
Plum Concrete
(D) ABUTMENT
1. Dobra Side - 21.0x10x28.60 m. + 22x17x3.22 m.
Well Cap + 4 Well of 6.0 m. outer dia of
18 m depth
2. Chanthi Side - 21x10x35 m.
15. (E) ROPES
1. Main Ropes - 2x12 No. of 66mm dia, Full Locked
Coil Wire Ropes (4x3 Arrangements)
2. Suspenders - 2 Nos at every 5m C/C Spiral Strands
of 25mm dia with cross spacing of
260mm C/C.
(F) CABLE GEOMETRY
i) Dip Angle toward Centre - 24.320
ii) Towards Anchor side - 24.860
iii) Centre to Centre distance of Cable
Bundle at the Mid Span
- 8.895 m.
iv) Angle of Convergence towards
Centre from both Tower
- 1.480
v) Angle of Convergence towards
Chanthi Side Anchor Blocks
- 2.150
vi) Angle of Convergence towards
Dobra Side Anchor Block
- 1.980
vii) Central Sag of Main Cable
towards Dobra Side Anchorage
- 0.482 m.
viii) Central Sag of Main Cable
towards Chanthi Side Anchorage
- 0.275 m.
ix) Horizantal Splay in Main Cable - 3.05 m.
16. (G) Tower Saddle - 4 No. with radius of Curvature of 1.32
m.
(H) Main Cable Clamp - 450x400 mm size with 3x4 Cable
arrangement.
(I) Link Shoe - 4 No. Allows longitudinal
displacement and rotation.
(J) Wind Shoe - 8 No.
(K) Expansion Joint - 2 No. (Modular)
(L) Central Stay - 2 No.
(M) Software Used for Design - RM 2009 and MIDAS/CIVIL
(N) Design Wind Speed - 39 m./sec (140.40 Km/Hr)
(O) Seismic Effects - For Zone IV
(Z) Zone Factor – 0.24
(I) Importance Factor – 1.2
(P) Thermal Consideration - - 50C to 450C
(Q) Deck - 14 mm thick Trapezoidal Closed Rib.
(R) Wearing Coat - Steel Deck Primer + 4 mm. Acrylic
water proofing membrane + 200µ
TackCoat + Two layer of 25 mm
Mastic Asphalt + One Top Layer of 12
mm. thick Stone Mastic Asphalt.
17. (S) LEVELS
1. Abutment Top - 850 m.
2. Tower Top - 908 m.
3. Deck Top at Mid Span - 854 m.
4. Full Reservoir Level - 830 m.
5. River Bed Level - 660 m.
6. Minimum Reservoir Level - 740.45 m.
Maximum Reservoir Level - 835.00 m.
Past Highest Flood Level - 831.40 m. (On Dated 20.09.2010)
7. Dobra Side Anchor Block
Foundation Level - 818 m.
Top Level - 855.50 m. and 854.50 m.
Main Cable Anchorage Level - 847.765 m.
8. Chanthi Side Anchor Block
Foundation Level - 847.50 m.
Top Level - 871.80, 872.80 m.
9. Dobra Side Abutment
Foundation Level - 800.18 m.
10. Chanthi Side Abutment
Foundation Level - 815.00 m.
11. Bench Mark Level near P.M.
Office
- 840.038 m.
12. Level of Rescue Helipad - 938.00 m.
13. Top Level of Tehri Dam - 839.50 m.
18. (T) Coordinate of Rescue Helipad Near Dobra
Latitute - 30026'48.7" N
Longitude - 78025'51.1" E
Altitude - 938.00 m.
(U) Nos of Villages and Population Benefitted
Block No. of Village Population (2011 Census)
Thauldhar 07 1438
Jakhanidhar 23 9557
Pratapnagar 130 62626
73621 Nos.
(V) Distance Reduced by Dobra Bridge
a) From New Tehri Lambgaon Pratapnagar
i) Before Submerging Bhaldiyana
HMV Bridge
- 65 Km. 86 Km.
ii) After Submerging Bhaldiyana
HMV Bridge
via Ghansali HMV Bridge - 162 Km. 150 Km.
via Dharasu HMV Bridge - 144 Km. 165 Km.
via Pipaldali LMV Bridge - 97 Km. 85 Km.
via Syansu LMV Bridge - 87 Km. 108 Km.
iii) After Construction of Dobra HMV
Bridge
- 55 Km. 68 Km.
19. b) From Rishikesh Lambgaon Pratapnagar
i) Before Submerging Bhaldiyana
HMV Bridge
- 124 Km. 145 Km.
ii) After Submerging Bhaldiyana
HMV Bridge
via Ghansali HMV Bridge - 232 Km. 211 Km.
via Dharasu HMV Bridge - 209 Km. 230 Km.
via Pipaldali LMV Bridge - 153 Km. 145 Km.
via Syansu LMV Bridge - 126 Km. 136 Km.
iii) After Construction of Dobra HMV
Bridge
- 114 Km. 135 Km.
(W) APPROACH ROADS
Dobra Side - 0.142 Km.
Chanthi Side - 1.625 Km.
(X) Aerodynamic Restriction
1. Bridge Closure for Movement of
Vehicles
- >25m/sec wind speed
(or 90 Km/Hr)
22. Remaining Works
Erection of Link Shoe, Wind Shoe &
Modular Expansion Joint.
Bed Block Casting.
Sand Blasting & Epoxy Painting.
Laying of Mastic Wearing Coat.
Miscellaneous & Load Testing etc.
Erection of Bridge Parts & Inspection
Way.
23.
24.
25.
26. Financial Progress
Sanctioned cost of work ` 149.945 Crore
Fund Received from NABARD-XXI ` 74.972 Crore
Fund Received from NABARD-XXIII ` 74.973 Crore
From THDC ` 00.00 Crore
Total Fund Received ` 149.945 Crore
Expenditure upto 15.08.2019 (Contract) ` 99.42 Crore
Expenditure upto 15.08.2019 (Project) ` 102.92 Crore
27.
28. OVERALL PHYSICAL PROGRESS OF PROJECT – 71%
S. No. Major Head % age
Physical
Progress
Remark
1. Tower Retrofit Work. 100% -
2. Erection of Catwalk. 100% -
3. Rope Haulage System. 100% -
4. Procurement of Saddle, Main Cable Clamp, Center Stay
Clamp & Suspender.
100% -
5. Fabrication of Bridge Deck Truss, Link Shoe, Wind Shoe. 100% -
6. Tower Base Strengthening. 100% -
7. Tower Base Grouting. 100% -
8. Main Cable Erection. 100% -
9. Cable Clamp Erection. 100% -
10. Suspenders Erection. 90% Work Stopped
due to
Suspender
Socket Slippage.
11. Wind Shoe Erection. 80% -
12. Installation of Hauling System for Deck Erection 100% -
29. S. No. Major Head % age
Physical
Progress
Remark
13. Procurement of Modular Expansion Joint. 100% -
14. Investigation of Rope Joint Failure & Anchorage System. 90% -
15. Dismantling of Suspenders. 100% -
16. Resocketing Work. 90% Work in Progress.
17. Suspenders Re-erection. 69% Work in Progress.
18. Deck Erection. 69% Work in Progress.
19. Deck Profile Correction, Bolting, Welding, Railing,
Wind Shoe & Link Shoe Installation.
- Work will be started after
Deck Erection.
20. Manchute Grouting. 100% -
21. Shortcreting. 100% -
22. Chanthi Side Bank Protection work. 45% Work in Progress.
23. Chanthi Side Approach Bridge and Box Cell. 100% -
24. Catwalk and Hauling System Removal. - Work will be started after
completion of Erection
Work.25. Laying of Mastic Wearing Coat. -
26. Sand Blasting and Epoxy Painting - Work will be started after
Erection Work.
27. Miscellaneous and Load Testing etc. -
34. Regarding permission to auction of unserviceable material
of Dobra-Chanthi Bridge, Engineer-in-Chief PWD
Dehradun recommended matter to Govt vide letter no.-
283/24(8)Yata-ka/2017 Dated 08.06.2017