Bridge No 111 over river the Ganges at Prayagraj.pdf

Rebuilding OF
BRIDGE Number111

Rebuilding of
Bridge Number 111
2024-25

Contents

• Introduction 01
• Rebuilding of existing Bridge No. 111 03
• Geotechnical Investigation 21
• Constrution of Well foundation &
Substructure 22
• Fabrication of Superstructure 66
• Erection of Girders 95
• Camber 121
• Bearing 125
• Media Highlights 128
• The End 129

A
t Rail Vikas Nigam Limited (RVNL), we have a rich legacy spanning over two de-
cades. Our story began with the objective of bridging the infrastructure gap on In-
dian Railways, implementing projects relating to the creation and augmentation of rail
infrastructure capacity on a fast-track basis, and raising extra budgetary resources for
Special Purpose Vehicle (SPV) projects. Our operational journey commenced in 2005,
and we have consistently received an ‘Excellent’ rating from the Department of Public
Enterprises for nine consecutive years.
Over the years, we have consistently endeavored to foster transparency across all our
business operations. This has helped us earn the trust of our clients and stakeholders
and enabled us to establish strong partnerships with them. While we strive to deliver
projects on time, we also ensure that our projects meet the highest quality standards.
Our efforts have been recognized, with us receiving Navratna status on May 1, 2023.
Adopting an asset-light model, we have gained a robust financial track record. Follow-
ing a turnkey approach, innovative execution models, and efficient contract manage-
ment practices, we have also gained a strong order book with a large share of projects
under execution. We undertake all stages of project development and execution,under-
scoring our expertise in translating concepts into commissioning.
02Rail Vikas Nigam Limited
Dubai
Maldives
Shri Prade ep Gau r
Chairman and Managing Director Director (Projects)
Shri Sanjeeb Kumar
Director (Finance)
Smt. Anupam Ban
Director (Personnel)
BOARD OF DIRECTORS
FOOT PRINT OF RVNL
Shri R ajesh Prasad
Director (Operation s)
Shri Vinay Singh
RVNL at a Glance
Footprint of RVNL

Shri Pradeep Gaur
Chairman and Managing
Director
Shri Vinay Singh
Director (Projects)
Shri Rajesh Prasad
Director (Operations)
Shri Sanjeeb Kumar
Director (Finance)
Smt. Anupam Ban
Director (Personnel)
Mission
To create state-of-the-art Rail transport infrastructure to meet the growing demand.
Vision
To emerge as the most efficient provider of Rail infrastructure, with a sound financial
base and global construction practices, for timely completion of projects.
Objective
To undertake and execute successfully project development, financing and implemen-
tation of projects relating to infrastructure, especially Rail infrastructure
• To mobilize financial and human resources for project implementation.
• Timely execution of projects with least cost escalation.
• To maintain a cost effective organizational set up.
• To encourage public private participation in Rail related projects managed by RVNL.
• To be an Infrastructure Project Execution Company committed to sustainable devel-
opment and environment friendly construction practices of Rail related projects in
the country.
• To acquire, purchase, license, concession or assign Rail infrastructure assets includ-
ing contractual rights and obligation with the approval of MoR whenever required.
Board of Directors

T
he Ganga Bridge Project, a monumental
feat of engineering and design, stands as
a testament to modern infrastructure devel-
opment over one of India’s most significant
rivers, the Ganga. Spearheaded by Rail Vi-
kas Nigam Limited (RVNL), this project in-
volved the construction of a new rail bridge
downstream of the existing structure near
Prayagraj. The bridge was designed to sup-
port two broad gauge (BG) lines and spans a
total length of 1,934.40 meters between piers.
The project was necessitated by the need
to enhance rail connectivity and accommo-
date increasing traffic demands. The exist-
ing bridge, built in 1912, was strengthened
in 1994 but remained insufficient for modern
rail requirements. The new bridge features
24 spans of 76.20 meters each, constructed
with open web steel girders in a Warren
truss configuration.
Introduction
This design ensures both strength and flex-
ibility, crucial for the dynamic loads experi-
enced by railway bridges..
The foundation of the bridge consists of cir-
cular well foundations, each with a diameter
of 10.50m and a steining thickness of 2.2m.
The substructures are reinforced cement
concrete (RCC) piers with semicircular cut-
waters, designed to reduce water resistance
and enhance structural stability.
Safety and quality were paramount through-
out the project. Regular safety drills, use of
personal protective equipment (PPE) and
round-the-clock medical support ensured
worker safety. Comprehensive quality as-
surance protocols, including detailed meth-
od statements and control systems, main-
tained high standards across all construction
phases
01Rebuilding of Bridge Number 111

Aerial view of newly constructed bridge
Side view of newly constructed bridge from
existing road bridge (Shashtri Bridge)
02Rebuilding of Bridge Number 111

Existing Road Bridge
(Shastri Bridge)
B
ridge No. 111 also known as “Izat
Bridge” spans the river Ganga, connect-
ing two significant holy cities: Varanasi and
Allahabad (now Prayagraj). The stations lo-
cated at either end of the bridge are Jhusi on
the Varanasi side and Daraganj on the Alla-
habad side. The bridge is situated approxi-
mately 2.2 km upstream from the confluence
point of the Ganga and Yamuna rivers.
This bridge was constructed by Bengal and
North Western Railway (B&NWR) Compa-
ny and the construction of this bridge was
started in 1909 and subsequently commis-
sioned in 1912. The substructure and super
structure of this bridge was designed for
B+25% MG loading of 1908. It comprises
of 40 spans, each of which is an Open Web
Girder (OWG) through type with a span
length of 45.72m.
The brick masonry piers of 21.489m height
are resting on 22.86m deep and 4.42m diam-
eter double octagonal masonry wells having
steining thickness of 1.016m. During Gauge
Conversion in 1994, this bridge was cleared
for single WDM2+7.67t/m loading after
strengthening of superstructure with Per-
manent Speed Restriction of 50kmph on ac-
count of SOD infringements.
History of
Existing Rail
Bridge
03Rebuilding of Bridge Number 111

Point of confluence of
river Ganga & Yamuna
Izat Bridge (Br No 111)
Existing Rail bridge
04Rebuilding of Bridge Number 111

The auspicious Kumbh Mela and the man-
agement efforts during the reconstruction
of Bridge No. 111
Mahakumbh Mela, held every 12 years
in Prayagraj, is one of the largest religious
gatherings in the world. It is celebrated at
the Triveni Sangam, the confluence of three
sacred rivers—the Ganga, Yamuna, and the
mythical Saraswati. The festival holds deep
religious significance for Hindus, who be-
lieve that bathing in these rivers during the
Mahakumbh purifies the soul and helps at-
tain moksha (salvation).
The origin of Kumbh Mela is rooted in Hin-
du mythology, particularly the story of the
Samudra Manthan(churning of the ocean),
where drops of the nectar of immortality fell
at four locations, including Prayagraj. This
event is commemorated through the festival,
which is organized at different places based
on astrological alignments of the Sun, Moon,
and Jupiter.
Kumbh Mela is not only a spiritual event
but also a cultural one, drawing millions of
devotees, sadhus, and religious leaders from
across India. It is a platform for religious
discourses, spiritual teachings, and cultural
exchange. Sadhus and saints from various
sects, often reclusive, come to the Kumbh,
offering spiritual guidance and participating
in ritualistic practices.
The Mahakumbh has historical roots dating
back to ancient texts like the Puranas, and its
modern significance extends to being a UN-
ESCO-recognized cultural heritage event. It
plays a vital role in promoting unity, cultur-
al diversity, and economic growth for the
region.
During the Mahakumbh Mela in Prayagraj,
constructing Bridge No. 111 presented sev-
eral challenges due to the massive crowds.

Crowd management was crucial, as millions
of pilgrims occupied the area, requiring des-
ignated construction zones and strict safe-
ty protocols to prevent accidents. Access to
the construction sites was limited, making
the movement of materials and machinery
difficult. This often-necessitated planning
deliveries during non-peak hours to avoid
disruptions.
Safety concerns were heightened, necessitat-
ing secure scaffolding, barriers, and well-de-
marcated construction zones. Additionally,
the proximity to the Triveni Sangam meant
special care had to be taken to prevent en-
vironmental damage, ensuring that no con-
struction debris entered the rivers.
Logistical challenges included coordinating
with local authorities and event organizers
to align construction activities with the fes-
tival schedule, ensuring that construction
progressed efficiently without disrupting re-
ligious events or the flow of people. Effective
planning was key to minimizing delays and
maintaining safety.
Site premises during Kumbh Mela
Tents installed during Kumbh Mela
surrounding Bridge Number 111

07Rebuilding of Bridge Number 111
Rebuilding of the Existing
Bridge No. 111
5. On Daraganj end there is serious land
problem and rebuilding of bridge no. 113
is already under separate sanction.
6. The bridge no.113 (11 x 7.61m) Arch
bridge is required to be dismantled and
closed except for one span of RUB.
• As there was a permanent SR of 50
Kmph and therefore a detailed estimate
amounting to Rs.293.53Cr was prepared
by construction department of North
Eastern Railway for rebuilding of new
bridge suitable for 25 T was submitted
to Railway Board in year 2010 and again
in 2013 at an estimated cost of Rs 293.34
Cr. According to this proposal the there
were 47 piers and center to center dis-
tance of the spans were P1-P36: - 48.615m;
P36-P40: - 24.31m; P40-P41: - 21.555m;
P41-P43: - 19.900m; P43-P45: - 13.400m;
P45-P46: - 19.9m; P46-P47: - 13.400m
Background
N
ER was trying to rebuild this bridge
since 2003 and therefore rebuilding of
IZAT Bridge No. 111 was sanctioned in 2003-
04 at an estimated cost of Rs. 129.90 Cr due
to its inability to support higher axle loads.
As construction of new bridge on the same
alignment was not feasible and therefore in
2007-2008 NER proposed to:
1. Construct a new bridge downstream of
the existing IZAT bridge due to site con-
straints.
2. The final location to be determined after
a hydraulic model study.
3. The new bridge should have the same
span but feature modern ballasted deck
type girders instead of the existing steel
open web girders.
4. There is no constraint of land on Jhunsi
side hence the curve starting from IZAT
bridge abutment will get flattened due to
proposed bridge in downstream.

Interior View of existing Izat Bridge

CBE/NER vide his letter 06.01.2016 to
EDCE/B&S/RB suggested that from
future point of view considering the re-
sidual life of stringers (10 year), cross
girders (25 year) and overstress in well
foundation, rebuilding of bridge should
be carried out under existing work. The
existing bridge can be strengthened on
the original alignment itself with the
provision of piles around the existing
wells and the existing piers are extended
on piles/wells to accommodate another
girder for doubling purpose.
• Then after diverting the traffic through
new girders, the existing girders may be
modified/replaced as per final decision
on the matter.
The above proposal could not be worked
out further as it was not workable. In exist-
ing bridge water clearance was only 2.8 Mtr
(HFL-Bottom of soffit). Use of prestressed
girder will reduce it further to unsafe level.
Also due to dense construction of buildings
at Daraganj approach construction activity
was not feasible.
Alternatives available for rebuilding
• Option 1 – Construction of new bridge
independently and introducing single
line working for diverting goods trains
via new bridge.
• Option 2 – Construction of double line
bridge keeping centre line of existing
piers unchanged. It does not require land
acquisition.
• Option 3 - Construction of double line
bridge by shifting centre line of piers to-
wards Matt, which requires acquisition
of railway land. Although as per avail-
able land record, Railway land is avail-
able for double line but most of the land
is encroached and several court cases are
pending.
09Rebuilding of Bridge Number 111

Outcome of the meeting held with Member
Engineering/Railway Board
• A meeting was held on 21.10.2016 in the Railway Board regarding the finalization of the
construction of a new bridge, No. 111, across the Ganga River in the Allahabad-Varanasi
section.
• It was decided that the construction of the new bridge, with a double-line substructure
and double-line superstructure in place of the existing bridge, along with doubling, would
be undertaken by RVNL.
• RVNL was to explore various options for constructing a new bridge suitable for a 25T axle
load at unrestricted speed, with a detailed estimate to be prepared once the scheme was
finalized.
Proposal for RVNL: -
Site Constraints: -
The ideal location for the new bridge would have been directly adjacent to the existing bridge,
maintaining the same alignment to facilitate construction and connectivity. However, this
option was rendered unfeasible due to several constraints:
1. Heavy Encroachment and Habitation: - The Daraganj end of the bridge approach is
densely inhabited and heavily encroached upon, complicating construction efforts.
2. Ongoing Legal Disputes: - Numerous long-standing court cases involving the land fur-
ther delay potential development.
3. Lack of Encumbrance-Free Land: - There is no available land free of encumbrances for
laying an additional track in this area.
4. Magh Mela Designation: - The available space is reserved by the Ministry of Defense for
the Magh Mela, limiting its use for bridge construction.
Final proposals
1. RVNL conducted a drone survey and proposed two alternative alignments for the new
bridge to the Technical Advisory Group (TAG). The 1st alignment, 15 meters downstream
of the existing bridge, was deemed unfeasible due to heavy encroachments and legal dis-
putes.
2. The 2nd alignment, approximately 125 meters towards the Jhusi side and 135 meters to-
wards the Daraganj side, crosses mostly vacant railway or military land. Despite technical
challenges with the skew and reverse curve on the approaches, this alignment is consid-
ered the most viable option for the project.
10Rebuilding of Bridge Number 111

11Rebuilding of Bridge Number 111
River bed between March
to November
River bed at time of Kumbh
mela (January- February)

Existing Izat bridge
During Flood
12Rebuilding of Bridge Number 111

13Rebuilding of Bridge Number 111
Technical Advisory Group (TAG)
The Technical Advisory Group (TAG) is a specialized committee formed to provide expert
advice and recommendations on critical engineering projects. For rebuilding of Br No 111
over river Ganga, RVNL in consultation with Railway Board constituted the TAG to leverage
the collective expertise of distinguished professionals in the fields of bridge engineering, geo-
technical engineering, structural design, and railway infrastructure. The TAG’s primary role
is to evaluate the technical aspects of the project, consider various design and construction
options, and ensure the project’s feasibility, safety, and cost-effectiveness.
Composition of TAG for the Ganga Bridge Project
• Shri R.R. Jaruhar: Ex-Member Engineering, Railway Board (Chairman)
• Dr. Prem Krishna: Professor Emeritus, IIT Roorkee (Member)
• Shri Bageshwar Prasad: Ex-MD, UP State Bridge Corporation (Member)
• Shri Amitabha Ghoshal: Steel Structure Specialist (Member)
• Dr. N. N. Som: Geotechnical Expert, Retired Professor, Jadavpur University (Member)
• Shri B. P. Awasthi: Chief Project Director (Bridge Works), North Eastern Railway
(Member)
• Shri Rajeev Verma: Executive Director (Bridges & Structures), RDSO (Member)
Term of Reference of TAG
• Location of the bridge site
• Design parameters of substructure, superstructure and any other guide lines for faster
execution.
• Requirement of model studies as the proposed bridge will be in close proximity of exist-
ing rail bridge
• Type of super structure & span arrangement
To assist TAC, a Preliminary Survey of the area was done with the help of drone including
marking of tentative alignment, taking cross section of the river, geotechnical investigation
of the river bed, collecting data of existing road & rail bridges on river Ganga such as Izat
bridge, Shastri Bridge, Curzon Bridge and over river Yamuna such as Naini Bridge; Hydro-
logical Data from CWC, GTS bench mark and these data were presented to TAC during
various meeting. The first meeting of TAC was held on 09.10.2017 in Delhi, followed by site
visit and further deliberations on 5th &6th of Nov near the bridge site.
TAG, after considering that the doubling of the section has been sanctioned and acknowledg-
ing that the existing bridge was originally designed for MG loading, recommended that it is
better to construct a new bridge for a 25 T axle load, which would be free from any restric-
tions. The existing bridge is also overstressed and has limited residual life. Any modification,
repair, or retrofitting would be prohibitively expensive and uneconomical.
After examining the site and the presentation, TAG is convinced that the encroachments
on the Daraganj side are particularly challenging, with a long-standing Matt in existence,

making it difficult to remove. This leaves practically no space for accommodat-
ing a double-line bridge alongside the existing one. Thus, the proposals consid-
ered by NER are not suitable and should be rejected. If pursued, given the con-
straints of space, it would take a long time and require blocking the existing traffic
to maintain the same track center. Both options are untenable and unacceptable.
Alignment of Bridge No 111
RVNL had proposed two alignments for consideration. The first alignment, which was 15m
downstream of the existing Bridge No. 111, depended on the removal of hard encroachments
and was, therefore, deemed unfeasible. The second alignment began at Daraganj station,
crossed the river with a slight skew and curved again to join Jhusi station. This proposal in-
cluded two options.
1. The first option involved a 2-degree curvature that permitted unrestricted speed, with
the curve and its transition extending onto the bridge deck at both ends.
2. The second option featured a 3-degree curvature, which imposed a speed restriction
of 95 km/h, lower than the sectional speed of 100 km/h. In this option, the transition
portion ended before the start of the bridge.
Both options under the second alignment had a skew of less than 5 degrees when measured
with respect to the existing bridge axis. TAG had earlier found the first alignment unsuitable
for the reasons stated.
The second alignment cleared all major hard encroachments on the Daraganj side. TAG was
satisfied that the soft encroachments, such as thatched shops and huts, could be easily per-
suaded to clear out. Most of the land belonged to the railways, military, or government,
making this alignment feasible and the best among all the proposals. On the Jhusi side, there
were no issues with encroachments or land. TAG had also explained that, given the existing
functional requirements and operational needs, it was not feasible to maintain a speed higher
than 90 km/h. Due to sharp curves ahead towards Allahabad, permanent speed restrictions
limited speed to 30 km/h, which could not be eased due to the geometry and heavy habita-
tion on both sides of the track.
There was no need for Daraganj to serve as a crossing station. The maximum permissible
curvature was 3 degrees, allowing a speed of 95 km/h. Upon site examination, it was found
that with this curvature and the transition length calculated for this design speed, the tangent
point of the transition curve (TPTC) fell outside the bridge on both sides. TAG also examined
the skew in the proposed alignment. The current flow condition already had some angularity
with respect to the two banks. The existing road and rail bridges spanned the entire width of
the river regime, which flowed between the two guide bunds in the form of roads on either
side of the river. The new alignment crossed at right angles to the current flow. Given the
stability of the river regime between several control points, the situation was not expected
to worsen. Even during the worst flood recorded in 1978, there was no adverse effect. TAG,
therefore, considered the so-called angled crossing of less than 5 degrees inconsequential
regarding hydraulic or structural considerations.
14Rebuilding of Bridge Number 111

The road bridge was about 200 meters downstream of the new proposed alignment, so there
would be no effect on it. Since the existing rail bridge would be abandoned after the construc-
tion of the new bridge, there was no need to consider any impact on it. In any case, it was
more than 150 meters downstream of the existing bridge and would remain unaffected. From
all considerations, the second alignment proposed by RVNL, with the modification of cur-
vature suggested by TAG, was deemed the best suited. It would facilitate fast, trouble-free
construction while meeting all hydraulic and operational requirements. TAG recommended
this approach accordingly.
Final Alignment
• A skewed alignment (2.7 degree) with distance on Daraganj being 180m and at Jhusi end
50m was proposed as
• Non availability of Rly land and heavy built-up locality,
• At 100 m distance from existing track at Daraganj side, encumbrance free defence land is
available free of inhabitation.
• Best fit curve was planned to allow max. permissible speed of 90 kmph due to presence of
sharp curves towards ALD just after the bridge.
TAG Recommendations for the Ganga Bridge Project
• Span Selection: After evaluating various span options, TAG recommended a 76.2m span
for its cost-effectiveness and structural suitability.
• Scour Considerations: The proposed alignment’s distance from the existing bridge mini-
mizes scour effects, with historical data indicating low scour levels.
• Girder Design: Both tracks are placed on the same girder to reduce pier and foundation
costs and facilitate easier maintenance and emergency response.
• Safety Protocols: Recommendations include designing the bridge to handle seismic forc-
es and ensuring the stability of foundations and superstructures.
• Design Discharge: TAG adopted a design discharge of 35,000 cumecs, 25% higher than
the downstream road bridge, to ensure the bridge’s resilience during peak flow condi-
tions.
• Historical Evidence: Citing examples from other major bridges, TAG assured that the
proposed bridge’s proximity to the existing bridge would not pose adverse effects.
RDSO Observations
• Necessity of Model Study: A model study is crucial due to the introduction of a new
bridge with a dissimilar span arrangement, which might adversely affect river flow pat-
terns, river training works, and nearby rail and road bridges.
• Recommendation for Model Study: TAG agrees with RDSO’s assessment and emphasiz-
es that a model study should be conducted. The study should consider the impact of the
new bridge on the downstream road bridge.
15Rebuilding of Bridge Number 111

Site Observations and Recommendations
Bridge Location
• Stability: The Ganga River’s course has been stable at the proposed bridge site for the
past 50 years, with no significant morphological changes. The confluence point of the
Ganga and Yamuna Rivers has also remained fixed and stable over this period.
Design Discharge
• There is no figure of maximum discharge available for Bridge No 111. The bridge register
maintained by NER states that maximum discharge was recorded in 1978 with HFL 88.48
M. The maximum scour is noted as 23 m below HFL.
• The CWC gauging station downstream of Sangam gives maximum discharge of 68000
Cumec in 1978. But this is the combined discharge of Yamuna and Ganga. The Yamuna
has a recorded discharge of 39925 Cumec at Kalpi upstream of Sangam. If this is deducted
from the combined discharge of 68000 Cumec, the Ganga has a maximum discharge of
nearly 28000 Cumec. On inquiry from UP PWD, the design discharge for Shashtri Road
bridge downstream of Bridge no.111 is 28333 Cumec which compares fairly well with
CWC discharge obtained after deduction of Yamuna discharge. The Curzon Bridge has a
design discharge of 35000 Cumec.
• Considering all this, TAG recommended that 35000 Cumec should be considered as de-
sign discharge for the foundation. Since this is corroborated by discharge actually record-
ed in 1978, there is no need to add 30% extra for occasional high discharge for design of
foundation. TAG also noted the historical maximum discharge obtained from CWC for
1978 as 17987 cumecs and recorded at Shahzadpur which is closest to proposed site and
is upstream. This figure is much lower than the design discharge adopted. TAG has ob-
served that as previously adopted 35,000 cumecs may be adopted without any addition-
ality of 30%.
Water Level and Afflux
• Minimal Afflux: The induced afflux upstream of the bridge is negligible at 1.0 cm. The
span arrangement and pier/well dimensions are designed to prevent significant afflux
during high flood conditions.
Aggradation and Degradation
• Riverbed Stability: The proposed bridge will cause negligible afflux, with no significant
changes in flow velocity or bed shear stress. Therefore, it will not cause aggradation or
degradation of the riverbed.
Proposed Bridge Length
• Adequate Waterway: The clear waterway of the proposed bridge is 1,874.40 meters,
which is larger than required by Lacey’s equation for alluvial streams, ensuring the bridge
length is sufficient.
16Rebuilding of Bridge Number 111

17Rebuilding of Bridge Number 111
Scour Depth
• Conservative Scour Depth: The maximum scour depth below HFL is set at 30.80 meters,
following guidelines from IRC: 5-1998, RDSO, and IRC: 78-2000. This is a conservative
estimate compared to the calculated 24.29 meters.
Highest Flood Level (HFL)
• Historical Data Alignment: The maximum gauge reading at Allahabad over the past 47
years was 88.03 meters in 1978. The proposed HFL for Bridge No. 111 is 88.48 meters,
which is in line with historical observations.
Aspect Costs
Historical Stability 50 years (no significant morphological changes)
Bridge Location 5.0 km from Chatnag, Allahabad
Yamuna River Max Discharge 47,600 m³/s (recorded in 1978)
Ganga River Max Discharge at Chatnag 68,000 m³/s (recorded in 1978)
Adopted Design Discharge 35,000 m³/s
Induced Afflux 1.0 cm (negligible)
Clear Waterway 1,874.40 meters
Max Scour Depth (HFL) 30.80 meters
Highest Flood Level (HFL) 88.48 meters
Max Gauge Reading (Historical) 88.03 meters (recorded in 1978)
Existing and newly constructed bridge
from Jhusi abutments

The Mathematical Model Study
After planning for the proposed bridge between the existing Izzat Railway Bridge No. 111
upstream and the Shastri Road Bridge downstream over the Ganga River at Allahabad.
RVNL had assigned the task of conducting a mathematical model study for this project toIIT
Roorkee. The study’s scope included:
• Assessing the impact of the proposed bridge on the Ganga River’s hydrodynamics, in-
cluding afflux, backwater, flow distribution, and bed changes.
• Calculating scour around the bridge piers/abutments for design discharge, considering
interference from existing bridges.
• Evaluating the bridge’s location, length, and span arrangements based on the modeling
results.
• Determining the need for river training/protection works and testing their effectiveness
in the mathematical model.
River course of Ganga near Up stream & downstream of confluence
point
The river course of Ganga has been examined via topo sheet & satellite images of dif-
ferent years in between 1970 to 2020 along with morphological study from Devprayag
to Farakka barrage and following conclusions were drawn: -
Flow patterns of river
Ganga since 1970
18Rebuilding of Bridge Number 111

19Rebuilding of Bridge Number 111
1. The river course near the proposed railway bridge is generally stable, although its main
channel tends to shift between the two banks. Between Phaphamau and the proposed
bridges, the river exhibits a wandering behaviour and widens significantly. This lateral
shifting in this reach has led to the protection of banks at certain locations.
2. The two existing bridges on the Ganga River near the proposed bridge, namely the Izzat
Bridge (No.111) and the Shastri Bridge, are aligned normally to the river flow. Both the
Ganga and Yamuna rivers are stable and well-channelized near their confluence point.
Downstream of the Ganga River, the course remains stable for about 6 km; however, beyond
this point, lateral shifting of the river has been observed. Despite these shifts, the confluence
point of the Ganga and Yamuna rivers has remained almost fixed and stable over the last 50
years, with no major changes.
The Summary of model study was as under: -
1. The Ganga River course at the proposed bridge site has remained stable for the past 50
years, making the location suitable.
2. The design discharge of 35,000 m³/s for the bridge is conservative, and the design high
flood level (HFL) of 88.48 m is appropriate.
3. The proposed bridge length is adequate, considering the stable river course, existing
bridge lengths, and well-defined banks.
4. The HEC RAS model shows minimal change in water level with or without the proposed
bridge, confirming its suitability.
5. Water level drops at the confluence point due to velocity differences, with upstream ve-
locity at 1.0 m/s and downstream at 3.75 m/s.
6. The computed water level just upstream of the proposed bridge is 88.60 m, with negligi-
ble afflux of 1.0 cm.
7. High bed shear stress downstream of the confluence is 7.0 N/m², while upstream it is 1.0
N/m² for a discharge of 35,000 m³/s.
8. The bridge’s placement will not alter the flow distribution across the Ganga river’s
cross-section, with maximum discharge between P-22 and P-23.
9. No significant difference in hydraulic parameters like water level, velocity, and bed shear
stress with or without the bridge.
10. The model predicts negligible morphological changes (aggradation and degradation) due
to the proposed bridge.
11. Computed scour depths around bridge piers align with the design scour depth of 30.8 m
below HFL.
12. Interference effects between the proposed and existing bridges in terms of scour depth
are negligible.
13. No river training work is required due to the non-migratory behaviour of the river, but
boulder revetment is suggested for abutment protection.
14. The proposed bridge will not impact the hydrodynamics, morphology, or flow distribu-
tion of the Ganga and Yamuna rivers, and the design is confirmed as appropriate.

Approval AspectDetails Date
Approval of GAD
General Arrangement Drawing (GAD) ap-
proved by CBE/NER after preparation and
review by the design consulting engineer based
on the actual field survey.
26.04.2018
Approval of DBR
Design Basis Report (DBR) approved by RDSO.
The DBR satisfies Indian Railways’ statutory
requirements for the design of foundations, sub-
structures, and superstructures of the proposed
bridge.
26.02.2021
Approval of STR
Schedule of Technical Requirement (STR) sub-
mitted and approved by RDSO for verifying the
site fabrication workshop for Open Web Girder
(OWG) fabrication.
17.09.2021
Approval of QAP &
WPSS
Quality Assurance Plan (QAP) and Welding
Procedure Specification Sheet (WPSS) submitted
and approved by RDSO through CBE/NER for
OWG fabrication.
05.10.2021

21Rebuilding of Bridge Number 111
Geotechnical Investigation
T
he field investigation involved sinking twenty-five (25) boreholes up to a maximum
depth of 64.10 meters below the existing ground or bed level at designated locations.
Standard Penetration Tests (SPTs) were conducted at 1.5-meter intervals in the boreholes as
per IS 2131-1981, with 'N'-values recorded for the penetration resistance.
Disturbed and undisturbed soil samples were collected for analysis, and rock core samples
were stored following IS 4464-1967 and IS 4078-1967 standards. The fieldwork commenced
on 05.11.2020 and was completed on 01.01.2021.
Location
Allowable Bearing Pressure at Founding Level of Well Foun-
dation as per IRS Well and Pile Foundation Code
AP1 496 t/m2
P2 418 t/ m2
P3 498 t/ m2
P4 482 t/ m2
P5 482 t/ m2
P6 466 t/ m2
P7 402 t/ m2
P8 to P10 372 t/ m2
P11 730 t/ m2
P12 to P24 372 t/ m2
AP25 372 t/ m2
Design Criteria for Substructure and Foundation
T
he exposure condition was maintained as “severe” as per Clause 5.4.1 of IRS Concrete
Bridge Code. The stress-strain properties of concrete and reinforcement steel shall be as
given in IRS Concrete Bridge Code and all reinforced concrete components shall be designed
as per Clause 15 of the same Code. The minimum grade of concrete, clear cover to reinforce-
ment steel and design crack width requirements for different elements of substructure and
foundation are given in the following table, which are as per the provisions of IRS Concrete
Bridge Code (CBC).
Substructure & Foundation
Elements
Minimum Grade
of Concrete
Clear Cover to
Reinforcement
Design Crack
Width
Pedestal M50 50 mm -
Abutment Cap / Pier Cap M40 50 mm 0.2 mm
Abutment / Pier M40 75 mm 0.2 mm
Well cap/RCC Well Steining M35 75 mm 0.2 mm
Top Plug M25 - -
Well Curb M35 75 mm -
Bottom Plug M25 - -

Cross Section of Well Foundation
Shape and size of wells:
T
he conventional “Circular” shaped wells with outer dia of 10.500m and inner dia of 6.100m
have been provided at all location from AP1 to AP25. The thickness of steining of circular
well is 2.200m, suitably armoured well curb of 4.250m depth. A suitably designed 9.500mX-
2.500m rectangular solid RCC pier with semi-circular on both end with dia of 2.500m.
A'A'
PLAN OF WELL FOUNDATION (FRONT FACE)
SCALE 1:100
A"A"
PLAN OF WELL FOUNDATION (SIDE FACE)
SCALE 1:100
A'A'
PLAN OF WELL FOUNDATION (FRONT FACE)
SCALE 1:100
A"A"
PLAN OF WELL FOUNDATION (SIDE FACE)
SCALE 1:100
22Rebuilding of Bridge Number 111

23Rebuilding of Bridge Number 111
Well foundation (Design & construction)
Design Hydraulic Parameters
T
he design hydraulic parameters i.e. Discharge, Waterway, H.F.L., Maximum scour depth
at Pier locations considered for Br. no 111 is as below: -
• Design Discharge (Q) = 35000 m3/s
• Length of Bridge = 1934.40 m between c/c of pier abutments
• H.F.L. = 88.48 m (msl)
• Silt Factor = 0.72
• Maximum Scour depth = 34.58m below HFL
The maximum discharge figure for Bridge No. 111 was unavailable at the time of design.
However, the bridge register maintained by NER indicated that the maximum discharge had
been recorded in 1978, with the highest flood level (HFL) at RL 88.48 m. The maximum scour
depth had been noted as 23 m below the HFL.
Design Discharge
A
ccording to the CWC gauging station downstream of Sangam, the combined maximum
discharge of the Yamuna and Ganga rivers had been 68,000 cumecs in 1978. The Ya-
muna’s recorded discharge at Kalpi, upstream of Sangam, had been 39,925 cumecs. After
deducting this, the Ganga’s maximum discharge was approximately 28,000 cumecs.
Discharge of Ganga-
28075 cum
Discharge of Yamuna-
39925 cum
Cumulative discharge-
68,000 cum

Upon inquiry with UP PWD, the design discharge for the Shashtri Road Bridge, located
downstream of Bridge No. 111, had been found to be 10 lakh cusecs (28,333 cumecs), which
aligned well with the calculated discharge after deducting the Yamuna’s contribution. The
Curzon Bridge had a design discharge of 35,000 cumecs.
Based on this information, TAG had recommended adopting 35,000 cumecs as the design
discharge for the foundation. Since this figure matched the discharge recorded in 1978, there
was no need to add the typical 30% margin for occasional high discharge in the foundation
design. TAG also noted that the maximum historical discharge recorded by the CWC in 1978
at Shahzadpur, upstream of the proposed site, had been 17,987 cumecs, significantly lower
than the adopted design discharge.
TAG maintained that the previously adopted figure of 35,000 cumecs could be used without
the 30% additional allowance. Moreover, a mathematical model study had been conducted
based on TAG’s recommendation, with no adverse effects observed.
Length of bridge
T
he length of bridge was determined considering the maximum shifting of river Ganga in
since 1970. The maximum width at HFL condition was found 1934.40. The length of the
bridge was also considered accordingly.
Maximum
width
considering
the historical
movement of
river Ganga
Width of
waterway at
HFL-1934.40
24Rebuilding of Bridge Number 111

01Rebuilding of Bridge Number 11125
T
he highest flood level was con-
sidered from the flood gauge
on pier of existing Izzat bridge. The
value was considered as 88.48 M.
The HFL is the main determin-
ing factor for estimating the scour
depth, grip length and subsequent-
ly the depth of well foundation.
Silt factor
T
he silt factor for estimating &
designing the scour depth as
per IRS foundation & substructure
code. Was taken as 0.720 as per
geotechnical investigation report.
Later during construction of well
silt factor was calculated for each
lift (approx.-2.7 to 2.9 m) and the
same was found in order with the
geotechnical investigation.
HFL marking at pier of
existing rail bridge 111
H.F.L (Highest flood level)
Depth of scour
Calculation of depth of scour: -
As TAG considered the discharge of 35000 cum was adequate no allowance was considered
in calculation,
Qf= m x Q (M is taken as 1) = 35000 cum
Calculation of regime width: - (Clause 4.5.3 of the Bridge Substructures & Foundation Code)
Lacey's regime with,
Pw = Pw =1.811 C(Q)1/2
Coefficient, c = 2.67
Regime width Pw = 904.61m
Calculation of effective linear waterway: -
• Total length of waterway at HFL, Li = 1934.40 m
• Assumed total obstruction width, Ow= 220.80 m (calculation shown below)
• Available effective linear waterway. Lw= 1713.60 m (more than the Lacey’s regime width)
Calculation of normal scour death: (Clause 4.0.3 of Bridge Substructures & Foundation
Code)
• Normal scour depth, D-0.473 (Q/f)1/2
• Sit factor of river bed material as collected from the soil investigation report, f = 0.720
• High flood level (HFL)= RL 88.480 m
• Normal scour depth, D = 17.203 m
• Normal scour level: - (HFL-D) = RL 71.217 m

Well cap top: - 75.350 m
Calculation of width of obstruction by pier foundation:-(Clause 45.3 of the Bridge Sub-
structures & Foundation Code)
Pier
Well Cap
Well Foundation
• Obstruction width of pier b3= 2.500 m
• Depth of pier below HFL h3 = 13.130 m
• Obstruction width of well cap, b2 = 10.500m
• Depth of well cap up to normal
• scour level h2 = 2.200m
• Obstruction width of well b1= 10.500m
• Depth of well cap up to normal scour level, h1=1.933 m
• Mean width of obstruction per pier foundation: -
• b = [b1h1+b2h2+b3h3]/[h1+h2+h3] = 4.415m
Proposed number of pier foundations inside the river, n = 25
Total obstruction width for all pier foundations On = nb = 110.379 m
Design total obstruction width, D= 2 On = 220.759m (same as assumed value)
Total obstruction width assumed calculation of effective linear waterway = 220.800m
Calculation of maximum scour depth: - (Clause 4.6 6 of the Bridge Substructures & Foun-
dation Code)
• Non-seismic condition
Maximum scour depth for pier well foundation for non-seismic condition, Dm=(2x-
D)=34.525m Maximum scour level = MSLm=( HFL -Dm) = RL 53.950 m
• Seismic condition
Maximum scour depth tor pier well foundation for seismic condition, Dm=(1.8xD)=31.073m
Maximum scour level = HFL -D mL = RL 57.407m
Calculation minimum grip length for Well foundation (Clause 69.1 of the Bridge Sub-
structures & Foundation Codel
• Minimum grip length for pier well foundation, Gp=Dm/3 = 11.608 m
• Highest possible founding level for pier well foundation MSL- Gp = RL 42.392m
• Consider highest possible founding level for pier well foundation = RL 42.000m
• Design founding levels for pier well foundation= RL 38.000m
13.130 m
HFL : - 88.480 m
1.933 m
Normal scour level: -
71.217 m
Well cap bottom: - 73.150 m
26Rebuilding of Bridge Number 111

A
s per the substructure and
foundation code, the well
was required to be founded with
adequate grip below the scour
depth. The calculated scour
depth was 34.525 meters. An ad-
ditional grip length, one-third of
the scour depth (11.508 meters),
was included in the design to de-
termine the founding level. Ini-
tially, the founding level was set
at 38 meters for all wells. How-
ever, it was later revised due to
the significant variability in the
underlying soil, which was ob-
served during the construction
of the well foundation.
To ensure the well-rested on a
sand layer with the desired bear-
ing capacity, the following crite-
ria were adopted based on the
designer’s recommendations:
• A minimum embedment of
5.0 meters in sand below the
bottommost clay layer.
• A minimum depth of 20.0
meters below MSL (maxi-
mum scour level).
Determining the founding level of the wells
In the case of P11, reboring re-
vealed a 15.9-meter-thick clayey
soil layer just below the origi-
nally considered founding level
of RL 38.00 meters. As a result,
it was decided to penetrate the
well further, past the clayey
layer, ensuring the foundation
rested on the sandy layer with
at least 5 meters of embedment.
During the sinking of wells P3,
P4, and P5, sudden drops were
encountered. Consequently, the
designer adjusted the founding
levels based on the aforemen-
tioned criteria.
01Rebuilding of Bridge Number 11127

Pier Mkd
Initial founding
level (R.L)
Revised founding
level (R.L.)
Remarks
AP1 38.00 m 22.00 m
P2 38.00 m 31.00 m
P3 38.00 m 26.00 m
P4 38.00 m 27.00 m
P5 38.00 m 27.00 m
P6 38.00 m 28.00 m
P7 38.00 m 32.00 m
P8 38.00 m 33.90 m
P9 38.00 m 33.90 m
P10 38.00 m 33.90 m
P11 38.00 m 11.50 m
Based on worst soil properties reboring
below RL +32.7 m
P12 38.00 m 33.90 m
P13 38.00 m 38.00 m
Not altered due to presence of highly weath-
ered sand stone below founding level
P15 38.00 m 33.90 m
P16 38.00 m 33.90 m
P17 38.00 m 33.90 m
P18 38.00 m 33.90 m
P19 38.00 m 33.90 m
P20 38.00 m 33.90 m
P21 38.00 m 33.90 m
P22 38.00 m 33.90 m
P23 38.00 m 33.90 m
P24 38.00 m 33.90 m
P25 38.00 m 33.90 m
Based on soil properties of reboring below
RL +26.0 m
28Rebuilding of Bridge Number 111

Construction of well foundation
D
uring the working season, most of the riverbed was dry except for the area where the
river had shifted. As a result, only four sand islands needed to be prepared for placing
the cutting edges. Twenty wells were constructed on the dry riverbed by leveling the ground,
placing the cutting-edge curbs, and subsequently sinking them.
Sand island prepared
in this section
01Rebuilding of Bridge Number 11129

Proposed Bridge
Top View of Well
Foundation during
construction
30Rebuilding of Bridge Number 111

Construction of sand island
A
s previously indicated, the river course at the site had a shallow depth during the work-
ing season, which allowed for the construction of sand islands. Four wells (P21 to P24)
were sunk by forming sand islands using a centrifugal sand pump. The top of each sand
island was raised to approximately 2 meters above the water level.
Due to the high-water flow, approximately 4 to 5 m/s, protective measures were taken to
prevent erosion of the islands. Bamboo piling hollow pipes & steel sheets were installed
around the perimeter, creating a cofferdam to safeguard the sand islands. Once the islands
were secured, their surfaces were compacted and leveled. Wooden blocks were then posi-
tioned to facilitate the precise placement of the cutting edge for well sinking.
Temporary Bridge
Sand Island (Protected
by cofferdam)

Bamboo piling , steel sheets and steel hollow pipes
used to prepare a cofferdam surrounding sand island

Approach for material transportation to sand island
A
temporary bridge was constructed for material transportation between the sand is-
lands and the riverbanks. Pipes were inserted into the riverbed using a vibro hammer.
ISMBs (Indian Standard Medium Beams) were placed both horizontally and vertically, with
chequered plates laid on top. From the cutting edge, shuttering, reinforcement, and concrete
were transported via this approach.
Temporary Bridge
Sand Island

Aerial View of
Temporary Bridge
during construction
Temporary Bridge
Material transportation for preparing cofferdam
through temporary bridge under progress

Fabrication of cutting edge
T
he function of cutting edge is to cut through the soil and the angular shape of the well
curb pushes the soil towards the dredge hole sump. The sharper the angle more efficient
it will be but a limit within 30 to 45 degree is recommended. In this case it was approximately
45 degree The cutting edge was fabricated at a yard approximately 2 km from the riverbank.
Two 200 x 200 x 20 mm angles were welded back-to-back, with the bottom angle stiffened
by a 20 mm thick plate. A 12 mm skin plate was then welded to the back of the assembled
angles. Subsequently, a 20 x 450 mm plate was welded to the skin plate, and the entire as-
sembly was bolted using countersunk bolts. The use of these bolts reduced friction during
the sinking of the well.
NORTH EASTERN RAILWAY
Cross Section of Cutting Edge
35Rebuilding of Bridge Number 111

ISA 200 x 200 x 20 for cutting edge Welding of ISA 200 x 200 x 20 members
Bending of cutting edge members
in suitable profie
Welding of cutting edge members
after creating circular profile
Bracket member assembling Welding of ribs at cutting edge
36Rebuilding of Bridge Number 111

Curb segments transported at site Positioning of curb segments
under progress
Well curb segments after inner and
outer skill plate fixing
DPT Test under progress
Alignment of brackets on cutting edge Welding of brackets after
welding with cutting edge
37Rebuilding of Bridge Number 111

Assembly of cutting edge
T
he cutting edge, along with the frame, inner skin plate, and outer skin plate, was fabricat-
ed in three sections and then transported to the site. After leveling the area where the well
was to be constructed, wooden blocks were placed at 1-meter intervals in a circular pattern.
The sections were then connected by welding and countersunk bolting. The slope of the in-
ner skin plate was carefully maintained to form a precise frustum. All welds were rechecked
using Dye Penetrant Testing (DPT) to ensure there were no leaks.
Surveying work to ensure the proper
positioning of cutting edge
Assembling of three well curb
segments at site
Well curb after final assembly
38Rebuilding of Bridge Number 111

Reinforcing the
cutting edge & curb
O
ut of the 4.250 m curb (includ-
ing the cutting edge), 2.275 m
was permanently covered with out-
er and inner skin plates to facilitate
swift sinking. The remaining por-
tion of the curb was left exposed to
the soil. After aligning and securing
the cutting edge, the shuttering for
the inner portion of the curb was in-
stalled in the shape of a concentric
frustum. Once the inner shuttering
was in place, reinforcement work
began. First, the threaded bond
bars (pre-threaded at the fabrication
yard) were positioned within the
cutting-edge shoe angle and bolted
in place. Bond bars were provided
in the cutting edge of the well foun-
dation to ensure a secure connection
between the cutting edge and the
steining, enhancing structural integ-
rity. These bars helped transfer forc-
es, such as skin friction and bearing
loads, from the cutting edge to the
steining, ensuring the well founda-
tion acted as a single unit. They also
prevented separation between the
cutting edge and the steining during
the sinking and load-bearing phases
while distributing loads evenly to
prevent localized stress concentra-
tions.
This ensures a smoother and safer sink-
ing operation, as well as long-term stabil-
ity After that balance reinforcement was
fixed and subsequently outer shuttering
of balance curb portion. From practical
consideration external diameter of well
curb was kept 75 mm more than out-
side diameter of well steining. This was
for the purpose of reducing skin friction
during sinking operation by keeping soil
close to steining above in a disturbed
condition with the help of the offset.
OFFSET
WELL CURB
STEINING
39Rebuilding of Bridge Number 111

Reinforcement binding and fixing work is under progress
Outer and inner shuttering work for well curb
After complete shuttering fixing Threading work for couplers
40Rebuilding of Bridge Number 111

Concreting
A
fter the curb shuttering had been completed, concreting commenced. The process was
executed using M35 grade concrete. To prevent segregation and reduce the risk of local
distortion in the plates due to lateral pressure, the concrete was carefully poured from a con-
trolled height of 1.25 meters. The curb concreting was performed continuously in a single,
uninterrupted operation.
Concreting work at site

Well curb after casting

Sinking of well curb
A
fter the casting of the curb, the shuttering of the outer portion was removed after 24
hours, while the inner shuttering was removed after 72 hours. Initially, a scale was
marked on the skin plate and extended up to the curb top on the concrete surface, which aid-
ed in understanding the sinking depth. For the sinking process, a crane with a grab bucket of
1.5 cubic meters capacity was employed. The initial stage of sinking was the most critical part,
as it ensured the verticality of the well. A sump was created in the dredge hole, following the
MoRTH guidelines, to prevent the well from sudden jumping. Once dredging commenced,
the verticality of the well was checked at frequent intervals. Four station was marked on both
X & Y axis of the well, so that level & coordinate can be measured in frequent interval during
sinking. The excavated material was deposited on the downstream side of the well.
Sinking work

Grab buckets
Sinking work using grab buckets

Steining (reinforcement fixing, Shuttering, concret-
ing & sinking)
A
steining thickness of 2.2 meters was provided for the wells. The reinforcement extending
from the curb was connected to the additional reinforcement using couplers, with no
lapping used in the vertical reinforcement of the steining. A threading machine was installed
in the yard to precisely thread the reinforcement, which was later coupled on-site using cou-
plers.
The height of the shuttering was typically determined based on the following three factors:
1. Ease of handling.
2. Buckling resistance.
3. Excessive weight of the unsupported upper section of the well.
A shuttering height between 2.7 to 2.9 meters was found adequate for meeting these require-
ments. This height facilitated crane operations for efficient handling, while also allowing
concrete placement at the necessary elevations. Shear key was provided after completing
casting of each lift so that proper bonding can be ensured along with horizontal shear resis-
tance.
Reinforcement threading work at workshop
Shuttering fixing for well steining
45Rebuilding of Bridge Number 111

Detail of Reinforcement used in Well Curb and
steining
REBAR OF WELL CURB
RING BAR FOR OUTER SIDE 32MM (23NOS)
RING BAR FOR INNER SIDE 32MM (24NOS)
RING BAR FOR TOP FACE 32MM (15NOS)
LINK BAR 16MM (72 NOS. EACH LAYER)
RING BAR 16 MM (72 NOS)
CIRCULAR BAR AT RING 29 NOS (16MM)
VERTICAL BAR OUTER SIDE 32MM (128 NOS)
VERTICAL BAR INNER SIDE 25 MM (88 NOS
REBAR OF WELL STEINING
RING BAR FOR OUTER SIDE 16 MM (150MM C/C)
RING BAR FOR INNER SIDE 16 MM (150MM C/C)
LINK BAR 12 MM (44 NOS. EACH LAYER)
VERTICAL BAR OUTER SIDE 32MM (128 NOS, 252MM SPACING)
VERTICAL BAR INNER SIDE 25 MM (88 NOS,224MM SPACING)
COUPLER DETAILS
COUPLER LENGTH FOR 32MM REBAR 64 MM
COUPLER LENGTH FOR 25MM REBAR 50 MM
THREADING DETAILS OF REBAR
FULL THREADING LENGTH OF 32MM REBAR 72 MM
FULL THREADING LENGTH OF 25MM REBAR 61 MM
HALF THREADING LENGTH OF 32MM REBAR 36 MM
HALF THREADING LENGTH OF 25MM REBAR 28 MM
Reinforcement threading work at workshop
46Rebuilding of Bridge Number 111

An offset of 75 mm was provided
in the overall diameter of the curb
portion compared to the steining.
Concreting of well steining
Curing after casting of well steining
47Rebuilding of Bridge Number 111

Sinking of well steining
S
inking of the well using ken-
tledge was commenced only af-
ter the steining had been cured for
a minimum of 48 hours for each lift.
The same grab bucket, with a ca-
pacity ranging from 1.5 to 2 cubic
meters, was used for sinking the
curb portion. For stiff clayey soils
encountered during the sinking
process, chiseling was performed
to ensure verticality and to control
the tilt and shift of the well after
casting each lift. Scale marking was
done after casting, using black and
white paint at 4 points—two along
the X-axis and two along the Y-axis.
During sinking, the coordinates and
levels were regularly checked to en-
sure the well’s verticality.
Sinking of well steining
Using of kentledge block
for sinking
Stage 1
Stage 2 Stage 3
Scale
Scale
Scale
48Rebuilding of Bridge Number 111

Sudden jump of P3, P4 & P5 well
D
uring the well-sinking operation for wells P3, P4, and P5, these wells unexpectedly
surged upwards by approximately 5 meters after having sunk to a depth of roughly 20
meters. This occurrence was due to the encounter with clayey soil strata during the sinking
process. At that time, the wells became untraceable. To resolve this issue, a two-stage well-
point dewatering system was deployed.
Well Point Dewatering Method
T
he well point dewatering method is a technique used to lower groundwater levels tem-
porarily. It involves installing a series of small-diameter wells (well points) connected to
a vacuum pump through a header pipe. These well points are spaced at regular intervals and
driven into the ground around the excavation site.
Once installed, the vacuum pump creates suction, drawing groundwater into the well points
and discharging it away from the site. This process effectively lowers the water table to be-
low the excavation level, enabling dry working conditions.
Cone of Depression
A
s the groundwater is extracted, a cone of depression forms around each well point. This
is the area where the water table is lowered in a shape resembling an inverted cone,
with the lowest point at the well and gradually rising away from it. The overlapping cones
of depression from multiple well points create a cumulative effect, resulting in a significant
reduction in the overall groundwater level across the entire site.
This method is particularly effective in sandy or loose soils and it was effective for the afore-
mentioned situation.
Despite substantial water recovery, the suction pumps were operated continuously until the
wells were relocated. After persistent effort, the wells were traced, and all debris was thor-
oughly cleared from both the reinforcement and the previous lift. Simultaneously, the rein-
forcement was re-secured while the pump operation continued.
Dewatering under progress by well point dewatering system
49Rebuilding of Bridge Number 111

Plan for Dewatering
50Rebuilding of Bridge Number 111

Dewatering wells Installation of dewatering wells
Pipe connecting dewatering wells After dewatering
01Rebuilding of Bridge Number 11151Rebuilding of Bridge Number 111
Reinforcement binding and shuttering work being carried out parallel to dewatering well

Maintaining Tilt and Shift
T
he daily readings of tilts of each well were tak-
en and recorded in the log books, and the tilts
whenever noticed were corrected immediately.
The main method used for correcting the tilts was
to introduce unequal dredging between the two
dredge holes if the tilt was in that direction and
sometimes use of kentledge over the higher side.
The maximum tilt observed was 1 in 234
The maximum shift encountered was 123 mm.
The final tilt & shift achieved at site: -
Pier Number Final Tilt Final Shift in mm
Permissible Limit 1 in 100 262.5 mm
AP-1 1 in 305 84
P-2 1 in 234 73
P-3 1 in 373 37
P-4 1 in 939 43
P-5 1 in 265 92
P-6 1 in 300 79
P-7 1 in 498 17
P-8 1 in 1485 42
P-9 1 in 267 123
P-10 1 in 357 115
P-11 1 in 495 73
P-12 1 in 939 97
P-13 1 in 509 37
P-14 1 in 420 10
P-15 1 in 582 17
P-16 1 in 470 28
P-17 1 in 328 22
P-18 1 in 742 36
P-19 1 in 371 66
P-20 1 in 274 57
P-21 1 in 582 74
P-22 1 in 369 100
P-23 1 in 445 58
P-24 1 in 664 24
P-25 1 in 390 51
52Rebuilding of Bridge Number 111

False steining
T
he elevation of the well cap was determined by considering both the low water level
(LWL) and the bed level. The bottom of the well cap or steining top was positioned
approximately 300 mm above the LWL. During the construction of the well caps within
the river course an additional external false steining wall was also provided as a retaining
structure, acting as a barrier between the well and the river’s high-water level. This wall
served as a protective barricade for reinforcement work on the well cap during periods of
elevated external water levels.
The design of the false steining wall accounted for the following worst-case scenarios:
i) External water pressure outside with an empty interior.
ii) Internal green concrete pressure inside with no external pressure.
A suitable corbel, extending all around, was provided to support the pressures exerted on
the steining wall.
VIEW AT A-A
(SCALE 1:50)
PLAN SHOWING WELL STEINING
A A
(SCALE 1:50)
DETAIL `1'
(SCALE 1:10)
DETAIL `2'
(SCALE 1:10)
DETAIL `3'
(SCALE 1:10)
PROJECT
TITLE
DESIGNED
DRAWN
SCALE
CHECKED
APPROVED
DATE
DRG NO. REV.
M.S.
28.07.2022
R1
S.C./S.H.G.
S.B.N.
AS DRAWN
P.K.R.
REV. DESCRIPTION DATE SIGNATURE
SHEET
1
TSD-22/1631/E/01
ITD Cementation India Limited
FALSE STEINING FOR WELL FOUNDATION
CONSTRUCTION OF 24x76.2 M SPAN IMPORTANT BRIDGE OVER
RIVER GANGA AT ALLAHABAD BETWEEN JHUSI AND DARAGANJ
STATION OF NER IN THE STATE OF UTTAR PRADESH INDIA
R1 GENERALLY REVISED 14.10.2022 M.S.
Detail ‘1’ Detail ‘2’
53Rebuilding of Bridge Number 111

Shuttering fixing for corbel of false steining
False steining after casting
54Rebuilding of Bridge Number 111

Bottom plugging
T
he bottom plugging was completed using M25 concrete to ensure proper sealing of the
well’s base, preventing water from entering. characterized by a cement consumption of
365 kg per cubic meter. The concrete was placed using a tremie pipe and hopper to ensure
proper flow and compaction.
To accurately estimate the required quantity of concrete, a bottom plugging level sheet was
prepared. Additionally, detailed records of the concrete consumption were meticulously
maintained in a dedicated bottom plugging register, ensuring precise documentation and
accountability throughout the process.
During the well-sinking process, the well encountered stiff clay, particularly Layer-II (hard
silty clay with occasional sand and calcareous nodules). This caused the soil to stick to the
curb and steining portion. To maintain the correct profile of the bottom plug, divers were
employed to remove the stiff clay before initiating the process of bottom plugging.
Layer-II: - Hard silty
clay with occasional
presence of sand and
calcareous nodules
Layer-IB: - Loose /Me-
dium dense/ dense silty
sand / fine sand with
occasional presence of
gravels nodules
Layer-III: - Medium
Dense / Dense / Very
Dense Silty Sand / Fine
Sand with occasional
presence of gravels
55Rebuilding of Bridge Number 111

Recuperation test
T
o accurately estimate the required quantity of concrete, a bottom plugging level sheet
was prepared. Additionally, detailed records of the concrete consumption were meticu-
lously maintained in a dedicated bottom plugging register, ensuring precise documentation
and accountability throughout the process.
A comprehensive bottom plugging recuperation test was conducted to rigorously evaluate
the permeability and effectiveness of the installed plug. The initial parameters recorded in-
cluded the start and stop times of dewatering for both the upstream and downstream sec-
tions, along with the initial water levels in the dredge hole. Concurrently, the river water
level was also documented. Following the dewatering process, the final water levels were
meticulously measured and monitored over a period of two days to assess any fluctuations.
All observations and data were systematically recorded and maintained in an appropriate
log for detailed analysis and future reference.
Using of divers for ensuring profile of bottom plug
Bottom plugging under progress
56Rebuilding of Bridge Number 111

Top Plugging
A
fter the bottom plugging and a successful recuperation test, the dredge hole was filled
with sand excavated during the sinking process, followed by the subsequent top plug-
ging. Before the top plugging, the surface of the filled sand was compacted, and a polythene
separator layer was provided to avoid contamination of the top plug.
57Rebuilding of Bridge Number 111
Filling of sands in dredge hole after bottom plugging
After top plugging

CHUM test of wells
“The Cross Hole Ultrasonic Monitor (CHUM) test is a non-destructive testing method used to eval-
uate the integrity of deep foundations, such as drilled shafts, piles or wells. It works by sending ultra-
sonic pulses between two transducers lowered into water-filled access tubes embedded in the concrete.
The system detects imperfections like voids, cracks, or areas of low-quality concrete.”
T
o ensure the integrity of the well foundation, a CHUM test was conducted. The Cross
Hole Ultrasonic Monitor (CHUM), compatible with ASTM Standard D6760, is designed
to detect subsurface imperfections through access tubes installed within deep foundations.
During the casting of the curb and steining, access tubes were installed along the entire depth
of steining of the well. After the final lift of casting, dual-function transceivers were lowered
into the water-filled tubes using pulleys, reaching the bottom of the well. Once the receiver
touched the bottom, both transceivers were pulled upward at a constant pace. Throughout
the process, ultrasonic pulses were continuously transmitted from the emitter to the receiver
along the entire length of the well, capturing the concrete profile and detecting any irregu-
larities.
GI pipe arrangement for CHUM test of well foundation 3
South
58Rebuilding of Bridge Number 111

CHUM was performed in M35 concrete. The details
were as below
Well no
Outer diam-
eter (m)
Inner Diam-
eter (m)
Planned Length
of Well (m)
Numbers of
tube used
Tube above
concrete
(mm)
Tube Diam-
eter (mm)
W20 10.5 6.1 35.00 30 1150 50
A typical CHUM test by 2D tomography result is demonstrat-
ed showing the uniform concreting of the wells
59Rebuilding of Bridge Number 111

Access tube continued as per
plan during casting
60Rebuilding of Bridge Number 111

Well Cap
T
he well cap served as the base for the pier, transferring all the loads encountered in both
Serviceability Limit State (SLS) and Ultimate Limit State (ULS) conditions to the well
foundation and subsequently to the ground. It provided a stable base for the pier shaft and
pier cap, which subsequently supported the superstructural elements of the bridge.
After the completion of the top plug, the outer reinforcements extending from the steining
were bent into an L shape by 750 mm, while the inner reinforcements were bent by 500 mm.
Additional reinforcement was added as per the design drawings, and the structure was cast
continuously without interruption, leaving the reinforcement for the piers exposed.

Pier Shaft

Pier Cap

Complete Pier

Pedestal

Fabrication of Superstructure
Span arrangement
T
he entire span arrangement of the superstructure consists of 24x 76.2 Mtr clear span and
effective span of 78.8 meter. The center-to-center distance of pier is 80.600 mtr. The super-
structure of the bridge will cater to accommodate 2 BG rail lines.
66Rebuilding of Bridge Number 111

Bridge configuration
T
he 76.20m main span girder was designed as a Warren-type truss based on economic fea-
sibility, ease and speed of erection, and maintenance efficiency, with a minimum number
of joints. The span of 76.20m was designed to accommodate two tracks on the same girder.
The girder design incorporated three degrees of redundancy.
The bridge is located in Seismic Zone III, which did not require special seismic consider-
ations. The design adhered to the IRS Seismic Code 2020, along with the latest correction
slips or any updated seismic codes.
This line falls under the Indian Railways network, where a loading of 25 tons (as per the 2008
guidelines) was recommended according to the Board’s stipulation. The approach ballast-
ed deck parapet was designed with adequate width to allow for Ballast Cleaning Machine
(BCM) operations.
67Rebuilding of Bridge Number 111

Material used for superstructure
F
or the main members of the truss (chords, verticals, and diagonals), steel of Grade E-410,
Quality B0, conforming to IS: 2062-2011, was used in accordance with paragraph 8.4 of
IRS B1. For rail stringers and cross girders, steel of Grade E-250, Quality B0, conforming to
IS: 2062-2011, was utilized.
A 8 mm thick mild steel chequered plate, conforming to IS: 3502, was employed for Gang-
ways, walkways, including the trolley refuge. H beam sleepers, as per RDSO-approved plans
with the latest alterations, were provided.
Circular Hollow Sections (CHS) of YST 310 MPA conforming to IS: 1161, were used for all
bracings and top rails of the handrail assembly. Plates conforming to Grade E-250, Quality B0
(IS: 2062-2011), were used for the posts, toe-guards, and mid-rails of the handrail assembly
along the pedestrian ways.
Based on the design requirements, High Strength Friction Grip (HSFG) bolts, as specified in
the IRS Steel Bridge Code, BS-111 Rev.6 and EN 14399 Part 1,2,3,5,6,7 & 9 and other relevant
codal provisions were proposed for in-situ connections. HSFG bolts of Property Class 10.9,
along with Direct Tension Indicators (DTI) washers, were used for fastening all connections
unless otherwise specified. The interface between the plies connected with HSFG bolts was
treated with aluminum metallization without any overcoating.
Method of Design
T
he steel superstructure has been designed using “Indian Railway Standard Code of Prac-
tice for the Design of Steel or Wrought Iron Bridges carrying Rail, Road or Pedestrian
Traffic”, (hereinafter referred as IRS Steel Bridge Code) which allows for “Working Load
Method of Design” only. The Design has been carried out based on relevant clauses of the
Indian Railway Bridge Rules, wherever necessary.
Quantity of steel used
T
otal quantity of steel used for one 76.2 Mtr span was 562 MT. Grade wise material used
are as below:
Grade of Material Required Qty (MT)
E 410 B0 Cu (MT) 8,490.00
E 250 B0 (MT) 4,206.00
Hollow Section (Yst=310 MPa)(MT) 792.00
Total (MT) for Main Girder 13,488.00
68Rebuilding of Bridge Number 111

Advantages of Copper Bearing Steel over General
Steel
Copper (Cu) adds significant advantages to steel and steel welds. It has an atomic number
of 29, an atomic weight of 63.54, a density of 8.96 gm/cc, a melting point of 1083°C, and a
boiling point of 2570°C.When added to steel in amounts exceeding 0.20%, Cu enhances atmo-
spheric corrosion resistance, creating what is known as weathering steel. Additionally, Cu
improves the mechanical properties of steel. In this project, Cu is added in the range of 0.17%
to 0.38% to enhance durability and performance.
Advantages of B0 Grade Steel over Br Grade
The primary advantage of B0 grade steel is its superior impact energy absorption capacity.
B0 grade steel has a minimum absorption capacity of 27 joules at 0°C, compared to Br grade
steel, which has the same capacity but only at room temperature. This makes B0 grade steel
more reliable and future-proof, especially for applications exposed to varying and low-tem-
perature conditions.
Material of Fastening
The superstructure members are primarily of welded construction. Majority of the members
are built up of plates welded to each other to arrive at the desired cross section. However, the
member components are connected at joints by HSFG bolts of property class 10.9 conforming
to BS-111 Rev.6 and EN 14399 Part 1,2,3,5,6,7 & 9 and other relevant codal provisions.
Welded Connections
AlAll chord and web members of truss are built-up with plates connected to each other by
Double bevel butt welded joints to achieve complete joint penetration (CJP). All flange to
web connections of dynamic load-carrying floor members (i.e. stringers & cross girders) are
of T-butt type joint conforming to fig. 7of IRS Welded Bridge Code as per clause 5.6. All such
welded joints are Ultrasonically tested (UT) as per approved QAP.
Connections Using High Strength Friction Grip
Bolts (HSFG)
RDSO has issued guidelines for the use of High Strength Friction Grip (HSFG) bolts on bridg-
es on Indian Railways – Report No. BS-111(Revision-6). All joints and attachments have been
proposed to be fastened with HSFG bolts conforming to EN 14399 Part 1,2,3,5,6,7 & 9 and
other relevant codal provisions of property class 10.9 as per design. Since, transverse welds
of attachments, weld in lap joints reduce the fatigue strength substantially. As such, welded
connections for attachments like that in case of battens are not recommended and bolted
connections have been proposed.
69Rebuilding of Bridge Number 111

Sl
no
Description of
Member/ Joints
Location
Required/
span
Material List
weight
Material
List weight /
Span
Material List
weight / Span
(MT)
1
Bottom Chord
Joint
L0 4 2209.107 8836.428 8.836
2 L1 4 987.692 3950.768 3.951
3 L2 4 2406.563 9626.252 9.626
4 L3 4 1182.627 4730.508 4.731
5 L4 4 2034.570 8138.28 8.138
6 L5 2 1557.229 3114.458 3.114
7
Top Chord Joint
U1 4 1887.988 7551.952 7.552
8 U2 4 932.301 3729.204 3.729
9 U3 4 1605.650 6422.6 6.423
10 U4 4 1044.721 4178.884 4.179
11 U5 2 1162.653 2325.306 2.325
12
Bottom Chord
BC1 4 4273.540 17094.16 17.094
13 BC2 4 3992.893 15971.572 15.972
14 BC3 4 5336.892 21347.568 21.348
15 BC4 4 5336.892 21347.568 21.348
16 BC5 4 6147.068 24588.272 24.588
17
Top Chord
TC1 4 3731.631 14926.524 14.927
18 TC2 4 3707.406 14829.624 14.830
19 TC3 4 4326.229 17304.916 17.305
20 TC4 4 4326.229 17304.916 17.305
21 End Raker ER 4 5760.698 23042.792 23.043
22
Diagonal
D1 4 3917.942 15671.768 15.672
23 D2 4 3372.917 13491.668 13.492
24 D3 4 3303.345 13213.38 13.213
25 D4 4 3019.943 12079.772 12.080
26
Vertical
V1 4 1372.407 5489.628 5.490
27 V2 4 1425.359 5701.436 5.701
28 V3 4 1424.916 5699.664 5.700
29 V4 4 1425.359 5701.436 5.701
30 V5 2 1424.916 2849.832 2.850
Total members fabricated
70Rebuilding of Bridge Number 111

31
Rail Cross
Girder
CG1 2 7301.992 14603.984 14.604
32 CG2 8 6345.856 50766.848 50.767
33 CG3 1 6345.856 6345.856 6.346
34
Rail Stringer
ST1 20 2270.353 45407.06 45.407
35 ST2 20 2270.353 45407.06 45.407
36
Rail stringer
Bracing
STBR 40 256.028 10241.12 10.241
37Seismic arresterSA1 4 736.487 2945.948 2.946
38 End Bracket EB 8 315.062 2520.496 2.520
39Bottom lateral
Bracing
BLB1 4 2978.311 11913.244 11.913
40 BLB2 6 2246.23 13477.38 13.477
41 Top Lateral TL 7 794.118 5558.826 5.559
42Sway Bracing SB 9 630.351 5673.159 5.673
43
Top Lateral
Bracing
TLB 8 1561.658 12493.264 12.493
44Portal BracingTL PL1 2 2213.507 4427.014 4.427
562042.395 562.042
71Rebuilding of Bridge Number 111

Fabricating Agency
T
he total fabrication work was done by The Braithwaite Burn and Jessop Construction
Company Limited, A Public Sector Enterprise, Known as BBJ at his own workshop estab-
lished at Jhusi, Prayagraj of near Jhusi station. Which is approximately 1.5 km from the bank
of river. This led to seamless material transportation to the working site.
Fabrication Yard Jhusi railway station
Stages of approvals before fabrication
A
pproval of STR: The Schedule of Technical Requirements (STR) was submitted on
22.07.2021 for approval by the Research Designs and Standards Organization (RDSO),
and it was approved on 17.09.2021. This document was essential for review and verification
by RDSO to ensure the site fabrication workshop met the necessary standards for the fabrica-
tion of Open Web Girders (OWG).
Approval of QAP, WPSS & WPQR: The Quality Assurance Plan (QAP) and Welding Pro-
cedure Specification Sheet (WPSS) were submitted on 28.07.2021 for approval by RDSO, and
the approval was granted through the Chief Bridge Engineer (CBE)/NER on 05.10.2021. The
QAP and WPSS form the foundation of the chronological assurance of quality that needed
to be maintained during fabrication, as per RDSO guidelines and railway standards, to en-
sure the output quality of the fabricated members. These documents were mandatory for
review and verification by RDSO for the fabrication of OWG at the site fabrication work-
shop. Throughout the entire fabrication process, strict adherence to these procedures was
maintained, and detailed registers were meticulously kept, including the Material Receiving
Register, UT Register, WPDR, Painting Register, and others.
72Rebuilding of Bridge Number 111

Flow Chart of Fabrication
Receipt of
Structural Steel
Physical
Inspection &
Measurement
Colour Coding
as per grade
of steel
Straightening Fit up
Welding
Stacking
Ultrasonic
Testing
Cutting
End FinishingDrillingMarking
Surface
Preparation
Metalizing &
Painting
NDT of Weld
Distortion
Control
Edge
Preparation
74Rebuilding of Bridge Number 111

Key Fabrication Activities
Steel Plate & hollow section Stacking
T
o prevent oxidation and surface damage, we stack steel plates on concrete floors with
wooden spacers, or 300mm above the ground using sleepers, covered to protect from
moisture. Plates are stacked to avoid twists and bends, with heights restricted to 900-1200mm
for easy handling. Mechanical handling uses two magnetic lifters (4-12MT each) and special
“C” clamps with chains for moving plates. We have a 1500 sqm area for stacking, with space
for hydra/trailer movement, and an additional 300 sqm inside the workshop managed by an
E.O.T. crane and feeding trolley on floor-mounted rails to reduce congestion.
Stacking of plate on
wooden Gutka
75Rebuilding of Bridge Number 111
Stacking of hollow and rolled section

Ultrasonic Testing (U.T.) of Steel Plates
1
00 % U.T. to detect internal defects and lamination in steel plates was conducted at site by
ASNT Level-II operator for plates of 12 mm and above using transducer with frequencies
2 MHz and 4 MHz and water as coolant.
Ultrasonic test of steel
76Rebuilding of Bridge Number 111

Steel Plate Cutting (CNC)
A
fter U.T. the plates are kept on levelled and raised (150mm above ground) cutting bed
for marking as per prepared cutting plan Precision cutting of steel plates was done to
specified dimensions using Oxy-fuel CNC and pug cutting machines.
Steel Plate & member Drilling
C
omputer Numerical Control (CNC) drilling to create precise holes in steel plates. CNC
machines automate complex operations using computer systems, and our CNC drilling
machine, powered by Hypertherm’s CAM nesting software. Radial drilling machines were
also used along with the CNCs for drilling members using jigs & fixures to maintain the pace
of fabrication.
Drilling by CNC and Radial machine
77Rebuilding of Bridge Number 111

Fit-Up of Steel Members
A
fter cutting, steel plates are placed on fit-up fixtures, which are fabricated to hold the
members as per the fabrication drawing. During fit-up, elements are tack welded with
temporary stiffeners to match the specified dimensions. Fixtures made from steel channels,
plates, and ISMB ensure accurate positioning. Post fit-up, the member is rigidly positioned
by stitch welding and bracing to maintain dimensional accuracy during welding.
Radial drilling machine
78Rebuilding of Bridge Number 111

Bevel cutting & finishing
B
efore welding, the edges of the plates were double-beveled using a flame cutter. After
profiling, the surfaces were ground to achieve a precise double-bevel profile.
79Rebuilding of Bridge Number 111
Bevel cutting by flame cutter and
checking of suitable profile

Welding of Steel Members
The joining of steel components was accomplished using various welding techniques such
as SAW (Submerged Arc Welding), MIG (Metal Inert Gas), and ARC welding. For welding
primary members, the CJP (Complete Joint Penetration) process was utilized, which signifi-
cantly enhances the structural integrity of the components.
Three types of welding were performed at the site:
1. Submerged Arc Welding (SAW)
2. Metal Inert Gas (MIG) Welding, also known as Gas Metal Arc Welding (GMAW)
3. Manual Metal Arc Welding (MMAW)
Two types of welds were used:
1. Double bevel butt weld
2. Fillet weld for secondary components
Precautions during Welding:
• Welding was carried out in accordance with the approved welding procedures and
by welders approved by RDSO, in line with the Welding Procedure Specification
Sheet (WPSS).
• Run-in and run-out were ensured for optimal weld quality.
• To prevent distortion, measures such as the use of proper welding sequences, clamps,
arresters, and frames were employed.
• Voltage fluctuations were avoided to ensure proper weld shape.
• Proper preheating of the parent material (to 150°C) and flux (to 250°C for 1 hour) was
ensured.
• The correct level of fixtures was maintained throughout the welding process.
Wire-Flux Combination:
• E250 grade welding was carried out using the W1-F1 wire-flux combination. This
resulted in a smoother weld but with increased concavity.
• E410 grade welding was performed using the W4-F4 wire-flux combination. This
weld was slightly less smooth compared to E250 but exhibited similar concavity. It
was the most critical weld, requiring greater control and careful execution.
• Butt welding was used in most of the structural members.
• During the rainy season, longer preheating durations were adopted to eliminate any
moisture, which could otherwise cause pinholes in the welds.
Gas Metal Arc Welding (GMAW):
• GGMAW was used in short-run welds where SAW was not feasible.
• CO
2
gas was used as the shielding gas.
• Horizontal welding was preferred for better weld quality, while vertical welding was
performed from bottom to top.
• Proper positioning of the job was ensured to maintain equal leg length.
• Spatters were minimized by maintaining a stick-out length of 1 to 1.5 inches.
80Rebuilding of Bridge Number 111

Tests Conducted at the Site
• Ultrasonic Testing (UT) for butt welds.
• Dye Penetrant Testing (DPT) to detect any pinholes, blowholes, or surface defects.
• Micro etching to assess penetration depth.
Distortion Correction:
Distortion was corrected after welding using a distortion correction machine, as well as reac-
tion frames with jacks.
81Rebuilding of Bridge Number 111
Pre-heating and subsequent
SAW welding for members
under progress

Double bevel Butt weld using copper wire as a back strip
Process for Using Temporary Copper Wire as a Backing Strip
for Double Bevel Butt Joint:
• The copper wire was cut to the same length as the girder.
• The copper wire was placed between the gap on the opposite side of the first root run
weld surface.
• The wire was aligned and clamped with the welded joint using a proper arrangement.
• A 3 mm root gap was maintained between the web and flange plate, corresponding to the
beveled surface.
• After depositing the root and multi-run weld metal on one side of the joint, the copper
wire was removed from the opposite side.
• The first root run was then removed by back chipping.
Advantages of Using Temporary Copper Wire as a Backing
Strip:
• The backing strip was used to prevent molten metal from flowing through the root gap
during the root run.
• It ensured 100% fusion with the base metal and helped achieve complete joint penetration
(CJP).
• The strip was easily accessible for fitting into the weld surface and was also easily remov-
able.
• The root gap allowed easy access for the electrode to the root face.
• The base metal remained unaffected during the back chipping of the opposite face of the
weld surface.
• The high thermal conductivity of copper (413 W/mK) prevented it from sticking to the
weld metal.
• It provided a clean and smooth weld metal surface.
• Copper has a high melting point and a moderate corrosion rate.
• A detailed sketch was enclosed for reference.
82Rebuilding of Bridge Number 111

Back Gouging After Deposition Of One Side Weld
01Rebuilding of Bridge Number 11183Rebuilding of Bridge Number 111

Inspection and Testing After Welding
1. Visual
• To identify any visible defects such as cracks, incomplete penetration, undercutting,
or excessive porosity.
• Leg length and throat thickness for fillet weld and reinforcement for “T” Butt weld.
2. NDT (Non-Destructive Testing)
• Dye Penetrant Testing (DPT): - The surface inspection technique using developer
and penetrant to detect cracks and surface defects in welds was conducted for each
type of weld. DPT was done to detect surface defects in welds like crack, pinhole etc
for further rectification.
Procedure: -
1. Cleaning of rust, dust, grease, oil and any foreign material from the weld surface.
2. Appling RDSO approved cleaner liquid by means of spray.
3. Testing temperature range of 15-60°C, and using post emulsified/solvent removable
penetrants, a minimum of 10 minutes shall be allowed as standard penetration time.
4. Removing excess penetrant.
5. Applied RDSO approved developer liquid by means of spray at the test surface to
accelerate bleed-out and to enhance the contrast of indications.
DPT Test of SAW welding
under progress
84Rebuilding of Bridge Number 111

Ultrasonic Testing of Weld Joints
A
s Complete Joint Penetration (CJP) welding was performed on all the main members of
the bridge, it allowed for 100% Ultrasonic Testing (UT) of the welds. Following the com-
pletion of the welding, Ultrasonic Testing (UT) inspections were carried out using non-de-
structive testing techniques, which are based on the propagation of ultrasonic waves through
the material. In typical UT applications, very short ultrasonic pulse waves, with center fre-
quencies ranging from 0.1 to 15 MHz, and occasionally up to 50 MHz, were transmitted into
the materials to detect internal flaws or to characterize the material properties.
Macro Etching of Weld Joints
1
-part HNO3 & 3 parts of H2O by volume
was used as an etching solution to check
the penetration of weld into parent metals.
This process is 100 % used to check the CJP
welds.
Macro Etching test
of welds
Profile of penetration

Straightening of
members
C
orrection of deformations in welded
members to ensure proper alignment.
Checking & stacking of
fabricated members
before blasting.
A
fter welding members were through-
out checking was done such as over all
length, width, hole to hole distance, pitch
ED etc. after checking the members were
stacked in yard premises
86Rebuilding of Bridge Number 111
Dimensional checking of members after fit up under progress
Straightening of fitted up members

87Rail Vikas Nigam Limited
Stacking of members after final fit up and subsequent inspection

Trial Assembly & B&S & M&C inspection
88Rebuilding of Bridge Number 111
Trial assembly of 76.2 m span resting on packing at each nodes
B & S and M & C inspection of members by RDSO offical
at workshop after Fit up

Copper Slag Blasting
D
ry copper particles ranging from 600 to 2000 microns are being used for surface prepa-
ration. The air pressure during the blasting process is maintained at no less than 4 kg/
cm², with the nozzle distance from the surface set between 150 and 250 mm. The surface is
finished to the Sa 2 ½ standard and is inspected using a standard comparator as per ISO 8501-
1:2007. To prevent rusting, painting is initiated immediately after sandblasting.
Crushed slag is used for sandblasting, and while IS: 6586 allows the use of special crushed
slag for surface blasting under paragraph 4.3, the code does not specify the graduation re-
quirements for the crushed slag.
After blasting members one coat of Aluminum spray was done within 4 hours with 3.15 mm
aluminum wire of 99.5% purity as per IS 2590. 2nd coat was completed within 8 hours. The
quality of the same was ensured by adhesion test & measuring the DPT as per IRS B1 2001.
01Rebuilding of Bridge Number 11189Rebuilding of Bridge Number 111
Blasting by using copper slag
Checking of Surace after blasting
by profile gauze

Metallizing work by using alumnium wire of 99.5% purity
after blasting under progress
90Rebuilding of Bridge Number 111

Painting of members
T
he first coat of wash primer (etch primer), Kansai Nerolac, Shalimar as approved by RVNL
to IS:5666 was applied initially. Following a 4 to 6-hour interval post-application of the
wash primer, the second coat, zinc chromatic primer conforming to IS: 104, was applied using
airless spray. The zinc chrome adhered to type 2 standards of IS: 51. Subsequently, the third
coat, aluminum paint confirming to IS: 2339, was applied. The girder part was dispatched to
the site after the third coat, which served as the first finishing coat or cover coat. Following
assembly and launching at the site, the second finishing coat of aluminum paint, conforming
to IS: 2339, was applied after touching up the primer and the first finishing coat.
Determination of Dry Film Thickness (DFT)
D
FT was checked in each step by elcometer as per guideline of IRS B1 2001. Each and all
members were checked and following criteria was ensured: -
Steps of painting DFT
Metalizing Average 150µm, minimum 110µm
Etch Primer Average 8-10µm,
Zinc Chrome Primer minimum 30µm
Aluminum Paint (Shop) Average 25µm
Aluminum Paint (Final) Average 25µm
91Rebuilding of Bridge Number 111
DFT checking after metallizing

92Rebuilding of Bridge Number 111
Application of Zinc Chrome primer after wash primer
Application of Etch / wash primer after metallizing

93Rebuilding of Bridge Number 111
First layer aluminium printing at workshop
Final DFT checking at workshop after first layer of aluminium painting

Torquing with HSFG (High Strength Friction Grip)
Bolts
F
or expedited project completion, HSFG bolts of 10.9-grade (with an Ultimate Tensile
strength of 1000 N/mm² and a lower yield stress of 900 N/mm²) were used as connecting
members for the bridge instead of rivets. The utilization of HSFG bolts also improved on-site
quality assurance due to their fixation flexibility. A total of 11.5 Lakhs bolts were utilized in
the Rail bridge, with each bolt’s torquing manually verified using a feeler gauge in accor-
dance with BS-111 Rev.6 guidelines. All bolts were sourced from RDSO-approved suppliers
such as M/s Pioneer Nuts and Bolts Pvt. Ltd, Brand-TUFF and M/s Panchsheel Fasteners,
Brand-PF. The consistency in the manufacturer’s bolting assembly was maintained through-
out the span, adhering to the aforementioned code.
During the painting process, the areas in close proximity to bolt holes were taped after the
application of etch primer, preventing additional coats of paint in those specific regions. This
measure was taken to maintain the crest and trough of the metalized surface, which played
a crucial role in generating friction within a high-strength friction grip (HSFG) bolted con-
nection.
Upon completion of the fabrication process, the members underwent shop bolting. This
involved a two-step procedure. Initially, the piles were snugly tightened using an impact
wrench, followed by torquing with a pneumatic torque wrench set at 960 Nm. After verify-
ing the compression of the DTI protrusion, the members were prepared for dispatch to the
bridge site. Upon arrival at the site, the members were erected using the designated process,
and the aforementioned bolting procedure was repeated on-site.
94Rebuilding of Bridge Number 111
Snug tightening of HSFG Bolts under progress

Erection of girders
T
he erection of superstructures represents one of the most demanding tasks in bridge
construction. Achieving success in this endeavor requires meticulous planning to ensure
structural integrity, safety of personnel, cost-effectiveness, and adherence to project time-
lines. In light of these considerations, erection of members of Br no 111 was done by three
methods. These methods were carefully selected so that the erection can be done in most
efficient way, which were: -
• Conventional Method with Trestle support.
• Cantilever method by overhead crane
• Cantilever method by ground-based crane.
Erection of girder on trestle support
T
hree spans out of the 24 were erected using the trestle method, two of which primarily
served as anchor spans. A total of 18 trestles, each consisting of 6 cubes, were used to
erect the 72.6-meter spans, with each trestle supporting the bottom nodal points of the span.
The trestles were stabilized by connecting horizontal and transverse bracing. The foundation
of each trestle was securely held in place by 28 M24 HD bolts, fastened into a concrete block
measuring 3.5 meters by 3.5 meters with a thickness of 350 mm. The foundation was con-
structed on a leveled PCC base with a 75 mm offset from the concrete block. The members of
the 76.2-meter span to be erected were delivered to the site and stacked at the erection loca-
tion. The launching of the members was carried out using a ground-based crane (TATA 955
ALC) with a capacity of [14 ton at 10 mtr radius] and a boom length of 130 feet.
Components of Trestle Erection:
• Camber jack – 4 nos 750 Ton jack
• Trestle cubes- 6 ton
• Grillage beam & tie beam – 1 tom
• Total weight: - 170 ton

The
Cantilever
Erection

The Cantilever erection (By Overhead or Deck erec-
tion crane) (65 MT)
C
antilever erection is a prevalent method in bridge construction across India, especially
for long-span bridges and structures crossing difficult terrains such as rivers, valleys,
or existing roadways. This method involves constructing the bridge in segments that are
extended outward from piers without the need for temporary supports beneath the bridge
deck, making it ideal for locations with obstructions or deep water.
A total of 13 spans were launched using the overhead crane. The crane was designed and
fabricated to erect the members of the non-standard 76.2-meter span girder. Each component
of the crane, such as the undercarriage, rotating platform, winch, jib, and central pivot pin,
was selected considering the span width, necessary lifting capacity, and required reach. The
dimensions for all crane members were chosen according to IS and ISO preferred numbers.
The crane was thoroughly tested on the ground before being assembled atop the anchor
span. It featured a rotating platform with a radius of 3.640 meters, along with a 1-ton central
counterweight and a 15-ton rear kentledge. The jib extended to a length of 15.6 meters. The
crane’s movement was facilitated by a 52 kg rail track fitted over the top chord of the span.
The crane’s carrying capacity was meticulously determined based on the specific reach re-
quired for each lifting operation, ensuring safe and efficient erection of the span members. –
Radius (For 90 ft jib) 15 m 21.3 m 27.4 m
Safe load in Ton 14.0 Ton 5.0 Ton 3.0 Ton

Assembling of Crane
Components
Erection of 90ft jib Placement of kentledge
Erection of rotating frame Placing of rotating frame
over crane base
Kentledge in form
of steel billets

The complete over head
crane after assembling over
anchor span

Components of Cantilever erection
• Kentledge at anchor span – 70 MT in addition to weight of anchor span.
• 1st erection link – 02nos. (11.5 Ton each)
• 2nd erection link- 02 nos. (8.5 Ton each)
• Temporary Link Prop: - 2 Nos
• Link plate: - 12 Nos
• Link pin – 06 nos.
• Bearing slab – 04nos (3.5 MT each)
• Buffer slab – 02nos (3.0 MT each)
• Link bracing: -02 Set
• Free and fixed type temporary Bearing: Free type – 04nos & Fixed type – 02nos.
• Hanging devises assembly: - 04set. (2.076 MT each)
• Turn fitted bolt (Grade-8.8): - 5800nos
Due to the presence of an end raker, the cantilever and anchor spans were connected by
erection links with bracings fitted crosswise. The center of the two-erection links is support-
ed by a temporary link prop, causing the links to act as a propped cantilever beam. The link
pins, having a diameter of 300 mm and a length of 1490 mm, serve as the tension connection
between erection links of anchor span and the cantilever span, while also allowing the rota-
tion of the cantilever span due to the gradual increase in dead weight. The buffer slab (with
a thickness of 230 mm at the center and 132 mm at the outer edges), which serves to reduce
shock by forming a barrier, functions as the medium for transferring compression loads from
the cantilever span to the anchor span through the bearing slabs (235 mm thick). The buffer
slab is convex on both sides, allowing it to compensate for the rotational moment encoun-
tered from the cantilever span. The anchor span at L0 joint rests on free bearings, L10 joint on
fixed bearing, while the cantilever span rests on free bearings, thus permitting the necessary
rotation of the span during construction and under various load conditions.
Tension Zone
Compression Zone
Tension
Compression
101Rebuilding of Bridge Number 111

“T
he interesting aspect of cantilever
erection is that when a cantilever
stands alone, the deflection at the free end
due to self-weight is less compared to when
it is connected to an anchor beam. The in-
creased deflection in a cantilever span,
when connected to a simply supported
span, is primarily due to structural conti-
nuity and load redistribution. The connec-
tion point allows for load transfer between
spans, introducing additional bending mo-
ments to the cantilever. This joint creates a
balance point for moments and shear forc-
es, resulting in increased bending moments
throughout the cantilever. Since deflection
is directly related to bending moment, the
cantilever experiences greater curvature
and thus larger deflections. Essentially, the
cantilever now supports not only its own
weight but also forces from the connected
span, altering its behavior and leading to
more pronounced deflections compared to
when it stands alone.”
102Rebuilding of Bridge Number 111

Link Shortening
T
o counteract the deflection due to stress reversal, self-weight & moment distribution be-
tween cantilever & anchor span the link was shortened between the 1st & 2nd erection
link subsequently making a upward gradient towards the landing pier of cantilever span.
This process was mandatory to ensure that the cantilever span to be landed desired location
at next pier. A shortening of 200 mm was made between U0 & U9 point compare to L1 & L9
point.
Proper landing of tip was achieved due to shortening of link
103Rebuilding of Bridge Number 111

The first link plate was designed with a slotted hole on the cantilever span side, while the
remaining two holes were of the same diameter with 1 mm tolerance as the link pin. The
purpose of the slotted (or oblong) hole was to accommodate backward movement when the
span landed on the next pier and rested on the packing. Once the span transitioned from
acting as a cantilever to a simply supported structure, compression forces shifted upwards
and tension forces occurred below, thereby allowing for the facilitated removal of the link
pin by hammering.
Due to the difference in the diagonals distaance of the link panel and panel of cantiliver span,
where the link prop acts as a vertical member, two different lengths of hanging devices were
used: one of 11.564 m and the other of 10.73 m.
As the link prop is attached to the bottom chord of the
anchor span, the distance to the next vertical increased,
affecting the diagonal.
Slotting
of hole
104Rebuilding of Bridge Number 111

The hanging device was manda-
tory during the erection of the
first and subsequent odd panels.
For the even panels, the bottom
chord was initially erected and
suspended using a chain block
with a 10 MT capacity. The chain
block was connected via a hanger
arrangement at the gusset of the
free end of the top chord and the
gusset at the junction of the top
and vertical members of the pre-
vious panel, on both the upstream
and downstream sides.
Subsequently, the diagonal mem-
bers were installed and connected
to the previously erected bottom
chord. Once connected, the chain
block was removed, allowing the
diagonal members to carry the
cantilever moment of the bottom
chord and the further erected
members of the panel.
For the odd panels, since the diag-
onals could not be used as hanging
members, the hanging device was
necessary. The erection sequence
included the bottom chord, cross
girder, BLB, and verticals. The
gradual increase in dead load due
to the erection of these members
caused slight deflection of the
panel from its original position.
When the diagonal members were
subsequently erected, it became
difficult to align the gusset holes,
necessitating the use of a jack (110
MT capacity) in the hanging de-
vice. This provided flexibility ac-
cording to the site conditions; for
example, when an upward shift
was required, the stroke of the
jack was reduced, along with ad-
justments in the fork bolt, and vice
versa for downward adjustments.
Detail of hanging device (HD-2) required for
erection of intermediate panels (odd panels)

Erection of top chord by erection crane
Erection of top chord
by erection crane

Hanging device Bottom chord assembled with
hanging device
Bearing slab (UT under progress) Link Pin (UT under progress)
Bearing slab (UT under progress) Link plate assembly with end racker
Components for Cantilever erection
107Rebuilding of Bridge Number 111

Assembly of all cantilever gadgets at the junction of
cantilever & anchor span
1st erection link 2nd erection link
Link
prop
Link pin
1
st
Erection Link
2
nd
Erection
Link
108Rebuilding of Bridge Number 111

Stages of Cantilever erection:
1. The leveling of L0 (upstream & downstream) and L10 (upstream & downstream) of the
anchor span was maintained at the same level.
2. Different components of the overhead crane, such as the undercarriage, track, rotating
platform, and jib, were lifted by the ground crane and assembled on top of the anchor
span.
3. The link prop was installed on both the upstream and downstream sides of anchor span .
4. The first erection link was installed with the link plate attached to the U9 point of the
anchor span using a link pin (ultrasonic testing of the link pin was completed before in-
stallation).
5. The feeding track was installed on the anchor span.
6. The bottom chord L0-L1, assembled with the bearing slab (on both upstream & down-
stream) along with the hanger device (HD-1), was fed through the feeder track.
7. The bottom chord was installed by suspending it with the link prop, and a buffer block
was placed between the bearing slab attached to L10 of the anchor span and the bearing
slab of the bottom chord.
8. After the bottom chord was installed, the vertical member was subsequently erected us-
ing the overhead crane.
9. Afterward, the vertical diagonal member with the link plate attached at the top was erect-
ed and fixed to the vertical member.
10. Immediately after, the second erection link was fed from the feeder track, subsequently
erected, and fixed with two link pins—one just above the link prop and another with the
link plate attached to the diagonal.
11. Following that, the bottom bracings and sway bracings were installed.
12. The process was repeated for erecting the next nine panels, where instead of erection
links, top chords were installed.

Some glimpses of Cantilever
Erection

Cantilever
by ground
crane

Erection by Ground crane: -
Eight Nos of span out of 24 spans were erected by cantilever erection process, The process
for the ground crane was similar as of cantilever erection, except of the member which were
erected by overhead or DEC crane they are now erected by ground crane.
Two no of cranes such as TATA 955 ALC having a boom length of 110 ft were used subse-
quently for erection of the members. The load capacity of the cranes were as follows
Radius (For 110 ft boom) 10.67 m 12.19 m 13.72 m
Safe load in Ton 14.580 Ton 12.130 Ton 10.320 Ton
The sequential process of erection by ground crane
Upon completion of the anchor span
launch onto trestle supports, the tighten-
ing of HSFG bolts and thorough inspec-
tions of all structural members, including
the bottom chord and top chord joints,
were carried out. The leveling of L0 (up-
stream & downstream) and L10 (upstream
& downstream) of the anchor span was
executed, ensuring that the L0 and L18
joints were aligned at the same elevation.
• Temporary free bearings were in-
stalled at the L0 joint (upstream &
downstream) and temporary fixed
bearings were placed at the L10 joint
(upstream & downstream) at the an-
chor span’s bottom chord BC1 (L9-
L10).
• The temporary vertical members, first
link, link pins, and link bracings were
fixed, followed by verification of bolt-
ed connections.
• The bearing slab at L10 (upstream &
downstream) was affixed to the end
bottom chord BC1 at (L9-L10).
• The buffer slab was placed on stools
at both the upstream and downstream
sides.
• The 1st bottom chord attached with
hanging device was erected subse-
quently vertical and end racker and
2nd erection link. Each panel were
erected gradually as mentioned in case
of overhead crane.
Placing Of Temporary Fixed Bearing
at Anchor Span L10 (U/S And D/S)
Placing Of Temporary Free Bearing
at Anchor Span L0 (U/S And D/S)
116Rebuilding of Bridge Number 111

117Rebuilding of Bridge Number 111

Assembly of all cantilever gadgets at the junction of
cantilever & anchor span
118Rebuilding of Bridge Number 111

Both cranes
were simulta-
neously work-
ing to erect
the members
(vertical in the
picture), with
one positioned
downstream
and the other
upstream. This
coordination en-
abled the com-
pletion of the
entire erection
process for all
members within
just 14 days.
119Rebuilding of Bridge Number 111

Camber
I
n OWGs, when a girder deflects, the truss shape and angles between members change,
introducing secondary stresses due to force redistribution at the joints. To mitigate these
stresses, girders are pre-fabricated with an upward deflection (camber), ensuring that under
load, the girder attains its nominal shape and that stresses remain as calculated for this condi-
tion. The girders were prestressed by assembling truss members with either shorter or longer
lengths than required, inducing forces that counteract secondary stresses.
In Br no 111, for 76.2-meter spans, the camber is designed for dead load (DL), superimposed
dead load (SIDL), and live load (LL), including the impact from the rail portions. The camber
is provided during the fabrication of members such as verticals, diagonals, top chord & end
racker members. The actual length is referred to as the nominal length, while the required
length to provide the camber is known as the camber length.
Achieving the design camber during fabrication was the most crucial part of the process,
as every member had to be fabricated with utmost precision due to the small difference—
sometimes as little as 2 mm—between the nominal and camber lengths. To achieve the de-
sign camber length, the compression and tension members were separated, ensuring that the
distances X and Y of the members remained fixed, as the gusset holes needed to align. The
camber length was adjusted by increasing or decreasing the length of Y; compression mem-
bers were fabricated longer than the nominal length, while tension members were fabricated
shorter than the nominal length.
X = distance between center of last rows of hole and C/L of node 1 or gusset
Z= distance between center of last rows of hole and C/L of node 2 or gusset
Y = camber length of the member- (X+Z)
CAMBER LENGTH
INTERSECTION
POINT OF NODE 1
X
Y
Z
INTERSECTION
POINT OF NODE 2
The perfect camber profile achieved after the erection of the
bridge demonstrates precise and accurate fabrication practices.

Camber drawing of 76.2 Mtr span

Comparison of design & achieved camber
For span P9-P10 (with DEAD LOAD)
T
he camber was measured on both the upstream and downstream sides using a total sta-
tion to obtain the most precise data. The prism was placed on top of the rail cross girder,
adjacent to the intersection points of each node, such as at locations L0 to L10 and L0’ to L10’.
Here is a refined version of your sentence:
“A comparison table is presented, showing both the design and observed data at each lo-
cation on both the downstream and upstream sides. This information is also represented
graphically.”
Down-Stream Side Up-Stream Side
Nodes
With Self
weight of steel
Theoretical
Camber
Actual
Read-
ing
Actual
Cam-
ber
(D/S)
Nodes
With Self
weight of steel
Theoretical
Camber
Actual
Read-
ing
Actual
Cam-
ber
(U/S)
L-0 0.0 1466 0 L-0 0.0 1466 0
L-1 37.0 1424 42 L-1 37.0 1424 42
L-2 65.5 1392 74 L-2 65.5 1392 74
L-3 90.7 1364 102 L-3 90.7 1364 102
L-4 103.5 1349 117 L-4 103.5 1349 117
L-5 109.7 1346 120 L-5 109.7 1346 120
L-6 103.5 1349 117 L-6 103.5 1350 116
L-7 90.7 1365 101 L-7 90.7 1365 101
L-8 65.5 1392 74 L-8 65.5 1390 76
L-9 37.0 1424 44 L-9 37.0 1422 44
L-10 0.0 1466 0 L-10 0.0 1466 0

Up-Stream Side Camber Profile with self weight of
steel of 76.2m span between pier P9-P10
Down-Stream Side Camber Profile with self weight of
steel of 76.2m span between pier P9-P10

Bearings
“Bearings are the most essential part of the bridge as it transfers all the loads to the substructure and
it also restricts the degree of freedom of a span to such extent that it will allow both traverse & longi-
tudinal movement but also restrict the span to move beyond certain limit”
The Indian Railways mandates the use of spherical bearings for spans exceeding 60 meters
due to their superior load-bearing capacity and compact structural design compared to other
bearings like POT-PTFE and elastomeric bearings. According to IRC-83 (Part II), the maxi-
mum allowable compressive pressure on elastomers is 35 N/mm², and on PTFE, it is 40 N/
mm². Given these constraints, spherical bearings are the preferred choice for bridge applica-
tions.
A spherical bearing consists of a concave and convex steel backing plate with a low-fric-
tion sliding interface, allowing for rotation through incurve sliding. For enhanced movement
capability, these bearings incorporate flat sliding elements, guides, and restraining rings.
The use of Ultra High Molecular Weight Polyethylene (UHMWPE) as the sliding material in
spherical bearings results in a more compact bearing size that fits within existing pier caps.
UHMWPE has double the compressive stress capacity of PTFE, leading to smaller bearing
sizes and extended service life.
For Bridge Number 111, 4 nos. bearing with their different functionality was used in a single
span such as: -
• Fixed Bearing (SB-1) [Vertical load (Max)-9160 KN, Horizon load-2835.9 KN]
• Free bearing (SB-4) [Vertical load (Max)-9160 KN]
• Longitudinal guided bearing (SB-2) [Vertical load (Max)-9160 KN, Horizon load-1188.8
KN]
• Transverse guided bearing (SB-3) [Vertical load (Max)-9160 KN, Horizon load-2746.8 KN]
The articulation of bearing is as below: -
125Rebuilding of Bridge Number 111

This arrangement makes the span fixed at one side and free at on another, the fixed & trans
guided bearing keep the span fixed & the free & long guided will allow the span for free lon-
gitudinal movement along the traffic direction, similarly the fixed & long guided will make
the span rigid in transverse direction and free & trans guided will make the span move in
transverse direction freely
The arrangement is so prepared that it will allow both transverse & longitudinal movement
but also to remain fixed in opposite side
The allowed rotations & moments are as follows: -
1. Fixed type: - Rotation: - 0.01 rad (+/-)
2. Free type: - Rotation: - 0.01 rad (+/-)
Displacement: - 75 mm (+/-) in longitudinal direction, 10 mm (+/) in transverse
direction)
3. Long guided: - Rotation: - 0.01 rad (+/-)
Displacement: - 75 mm (+/-) in longitudinal direction
4. Trans guided: - Rotation: - 0.01 rad (+/-)
Displacement: - 10 mm (+/-) in Transverse direction
Diagram of bearing used in bridge: -
Long guided Spherical Bearing Transuided Spherical Bearing
Free Spherical Bearing Fixed Spherical Bearing
126Rebuilding of Bridge Number 111

Quality assurance during manufacturing
A total 96 nos. of bearing were required for Bridge Number 111. A summarize table of details
of spherical bearing procured is as below: -
The spherical bearing was installed under the specialized supervision of the OEM represen-
tative and RVNL engineer in charge.
During the fixing of the bearings, the girder was aligned by traversing in jacks. The level at
the four corners was maintained at the same level using level instruments, and the alignment
was controlled using a total station instrument.
After fixing the bearings, the final line, level, and camber of the girder were checked and re-
corded. The gauge for measuring girder movement was set to 0 after installation.
Work Sequence for Bearing Fixing: -
1. Span support was shifted from temporary arrangements to a stool by jacking.
2. Temporary pedestal was dismantled.
3. Welding at the bearing contact surface of the bottom chord was flushed (if required).
4. Bearing was fixed with the end bottom chord joint.
5. Center line was marked on the pier cap.
6. Span was aligned.
7. Span was lowered to the required level.
8. Jack was shifted, and the span was supported on a stool.
9. Pedestal reinforcement was bound.
10. Dimensional checking and pedestal center line checking with bearing center line were
conducted.
11. Shuttering for casting of the pedestal was completed.
12. Pedestal was manually cast using OPC M-50 Grade concrete.
13. Top 20mm was grouted using proper grouting material.
14. Pedestal was de-shuttered.
15. Pedestal was cured for 28 days using a gunny bag or hessian cloth.
16. Stool was removed.
17. Span was supported on the bearing after 28 days.
Inspection Authority RITES
Manufacturer MAGEBA
Proof Checked by Professor, IIT Guwahati
Service Period 50 years
Guarantee Period 15 years
Defective Bearing replacement
period
36 months from date of supply or 24 months from
date of installation, whichever is earlier

Media Highlights

The End
Aerial view of bridge after completion

By
Vikas Chandra
Executive Director / NE / RVNL
Riddhiman Bhowmik
SSE / CIVIL / RVNL

REGISTERED OFFICE
1st Floor, August Kranti Bhawan, Bhikaji Cama Place
R.K. Puram, Delhi, South Delhi - 110066
CIN: L74999DL2003GO1118633
Email: [email protected], Website: www.rvnl.org, Phone No.: 011-26738299, Fax: 011-26182957
Rcil Vikcs Nigcm LimitedRcil Vikcs Nigcm Limited @rvnl_officl@[email protected]

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