This document provides details about the Kalia Bhomara Setu road bridge over the Brahmaputra River in Tezpur, Assam. It summarizes that the bridge connects NH 52 and NH 37 on the south bank via a 23km link. It describes some of the complex foundation work, including sinking 27 wells up to 56m deep, and constructing two well foundations with caissons up to 12m deep. The superstructure consists of balanced cantilever pre-stressed concrete box girders with 120m spans. Over 170,000 cubic meters of concrete and 12,000 metric tons of reinforcing steel were used.

1. KALIA BHOMARA SETU
ROAD BRIDGE ON THE RIVER
BRAHMAPUTRA
TEZPUR,ASSAM
By : Vishweshwar Rao Narla

2. KALIA BHOMARA SETU

3. 1 INTRODUCTION
 The River having a catchment area of
3.8lakh sq.km flows in the most
unpredictable manners, occupying space.
 The Project Connects NH 52 & NH 37 on
south bank, through a 23km long link.

4. 2 FOUNDATION
 Out of 27 foundations 25 are Open Wells
 The North Abutment and Pier No.1 are on Raft
Foundations.
 The Wells have been Sunk to 56m LWL, mainly
from scour and seismic considerations.
 The strata encountered were dense sand mixed
with pebbles.
 With elaborate monitoring at each stages of
sinking, it has been possible to position all the
wells within permissible limits of the Tilt & Shift
each well costing of Rs.80 Lakh and involving
5000m of concrete was completed within an
average period of 90 days.

5. WELL WORK IN PROGRESS FOR THE BRIDGE PILLAR

6. 3 WELL FOUNDATION
 Two of the Well-Foundations required of
caissons in depth of water ranging from 8m to
12m 290t of steel was required to be fabricated
for these caissons.
 Water ballasting of sinking-pontoons to ferry
across the construction materials, for
simultaneous working on a number of
foundations, a large fleet of marine craft was
deployed it consisted of tugs.
 20 barges and a number of country boats for
concreting, batching plants of 950cu.m/day
ccapacity were installed.
 9 SLD cranes, 3 Crawler cranes and stand
cutter dredger pumps were used for sinking
Well Foundations.

7. WELL WORK IN PROGRESS FOR THE BRIDGE PILLAR

8. 4 PILE DRIVING
 Pier No.1 founded on a 2m thick RCC Raft which is
held down with 96 rock-anchors on North and 6 RCC
bored piles of 1.5m dia on South.
 These piles are driven with CASSAGRADE pile-
driving equipment.
 Substructure is hollow circular RCC piers of 12.5m
height constructed with concrete of grade M-300. it
being a navigable river, the height of the piers has
been determined to Cater to the navigational
clearances.
 RCC feeders have been provided to protect the piers
from any possible damage due to stray vessels.
 The pier-cap is made 6.5m square to facilitate the
construction pier-head.

9. 5 CAISSON GROUNDING
 While sinking the Well for Pier No. 2 near
Bhomoraguri Hill, boulder stratum at a depth
of 26m below LWL was met with services
deep sea divers were utilized for sinking the
Ell through this stratum, by under water
blasting.

10. 6 SUPER STRUCTURE
 The distance of 120m between consequence
pier-center is spanned by two 52.5 long
balanced Cantilever from the piers and a 15m
long suspended span in the middle.
 The cantilever portion is a single-cell PSC Box
Girder in concrete of grade M-425 using special
cement, post tensioned with 90nos of 24x8mm
dia HTS cables.
 The cantilever arm has been constructed in 11
segments of different lengths.

11. THE 15 METER SECTION IN BETWEEN TWO CANTILEVER OF 52.5
METERS BEING FITTED IN PLACE

12. CANTILEVER SECTION WORK UNDER PROGRESS

13. VIEW OF WORK INSIDE A BOX SECTION OF CANTILEVER

14. 7 MASTIC SURFACE
 For the construction o the cantilevers, the Bridge-
Builder system has been imported from Norway for
the first time in India.
 An average cycle of 5days has been achieved here
for segment construction, as against the accepted
international average of 7days; FREYSSINET
system has been adopted for pre-stressing.
 For manufacture and placing of large volumes of
high grade concrete, electrically controlled automatic
ELBA batching plants along with concrete pumps
were imported from West Germany.
 The total installed concreting capacity was of the
order of 1000cu.m/day.

15. THE JOINTS BETWEEN TWO SECTION OF CANTILEVER

16. 8 GIRDER LAUNCHING
 The Bearing at the interface of a cantilever
and a suspended span is specially
designed to cater to complex seismic
movements.
 These consists of a combination of
spherical knuckle and PTFE stainless steel
sliding surface for surface for free end
bearings and spherical knuckle cum
electromeric pad for fixed end bearings.
 The majestic deck is provided with 25mm
thick layer of Mastic Asphalt.

17. THE HOLLOW CANTILEVER BOX SECTION , INSIDE VIEW

18. 9 RIVERINE QUARRY
 The requirements of aggregates for the
bridgework met with from a reverine quarry on
the North bank.
 For the Guide-Bund the required quantity of
man-size boulders was collected from hill quarry
on the south bank for which 30t of explosives
were used.
 Both these quarries were 50-60km away from
the work site and this necessitated deployment
of a large for verifying grades of concrete, a fully
mechanized aggregate processing plant of 150
t/hours capacity was set-up.

19. 10 CRUSHING PLANT
 The project site is situated in a remote corner of
the country.
 Due to non-availability adequate quality of steel
and cement in the proximity, their procurement
involved long leads in distance and time.
 Therefore large storage capacity to the tune of
24000t for cement and 14000t for steel, had to be
developed.
 To feed electrical power to the work site, power
supply network was developed consisting of
33KVA overhead transmission lines for a length of
30km along with four sub-stations.
 River crossing was arranged by laying under water
XLPE Cables. Necessary infrastructure was
developed at work site, to house 4000 workmen
including Engineers and Supervisors.

20. 11 TECHNICAL DETAILS
Structural details :-
a) Bridge:
1) Spans : 24 spans of 120m
and two shore-spans discharge
of 67.5 m
2) Total length : 3015m
3) Main span : Balanced
cantilever Pre Stressed concrete
box �girder of 52.5m site with
central R. C. C suspended span
of 15 Meter.
4)Clear carriage way : 7.5m
5)Footpath :1.5m wide on either
side.
6) Sub-structure: : 12.5m high
hollow Circular R.C.C pier with
Square pier-cap.
7)Navigational clearance :
12.0m for central 90m.
8) Foundation : 56 m deep 12m
dia.
b) Guide-bund :
 1) Length : 1633m on U/s and
405 m on D/S.
 2) Shape : Elliptical
 3) Sausage crate size : 2.55m x
1.5 m (0.90 to 1.05)
 4) Top level : R.L 71.10 m
 5)Top width : 9.0 m
 6) Side slopes : 2.5 : 1.
 7) Pitching on front slop : 1.2 m
thick grouted with 1:3:6
concrete over 0.3 m thickfilter.
 8) Pitching on rear slope : 0.3 m
thick boulders over 0.15 m
c) South Approach Bank :
i) Length : 1678 m
ii) Top width : 12.0 m
iii) Side slopes : 2.5: 1

21. 11 TECHNICAL DETAILS
Hydraulic data :-
1) Maximum design : 92,278
Cumecs.
2) Minimum discharge : 4,000
cumecs.
3) Design H.F.L : R.L.67.5m
4) Maximum mean Velocity :
4m/sec.
5) Average L.W.L : R.L 610m.
6) River width at bridge : 4,683m
7) Maximum design scour level a)
Normal condition : R.L.24.76m b)
Seismic condition : R.L.29.03m
Material consumed:
a) Bridge :
1) Total concrete quality : 1,70,000
m3
2) Total reinforcing steel : 12,000
mt
3) Cement : 82,000 mt
4) Coarse aggregate : 1,50,000m3
5) Sand :75,000m3
b) Guide-bund and South
Approach Bank
1) Earth-work : 19 lakh m3
2) Stone �work : 8.2 lakh m3
3) G.I wire : 5300mt

22. 12 CONSTRUCTION SHEDULE
 The river offers only 135 days for normal river-
bed working, as compared to 180-210 days for
other major rivers of India. This necessitated
large-scale mechanization for foundations and
elaborate arrangements for superstructure
works even during high-floods. The Guide-bund,
involving 19 lakh m3 of earth-work and 8.2 lakh
m3 of boulder-work, was required to be
completed within 135 days and needed
deployment of machinery worth Rs.11 Crores for
the work. The actual time of completion of each
work, is as follows : -

23. 12 CONSTRUCTION SHEDULE

24. 12 CONSTRUCTION SHEDULE
 Maximum concreting done in one day 950 M3
 Maximum sinking done in one day 19 Meter
 Average rate of sinking of wells 1.3 M/day
 Max amnt of work done for bridge in one day Rs.6.5 lakh
 Maximum concreting done in one season 71,000 M3
 Maximum cement consumed in one season
23,800mt
 Maximum sinking done in one season 703m
 Max no. of cantilever segments done in one month 28
 Maximum amount of earth-work done in one day
16,800m3
 Max amount of boulder-work done in the one day 9,350m3
 Max amt of work done for Guide-bund in one day Rs.11.6
Lakh.

25. 13 CONTRACTORS
 a) Main Bridge :
M/S Hindustan Construction Company Ltd,
Bombay.
 b) Guide-bund and South Approach
Bank : M/s. Jai Prakash Associates, New
Delhi.
 c) Bridge bearings and Expansion
joints :
M/S Metal Engineering & Treatment
Co.(P) Ltd, Calcutta.