Under Writting: This post shall be published in HMIS News later of DoR soon.
Summary :
Bhapsi Bridge along E-W Highway collapsed in flood dated 13th June, 2019. It was opened to traffic by installing modular panel Belly Bridge for short term. Due to high traffic and heavy load it was damaged and repaired many times and the way of operation was questioned by people of different sector demanding LoS as per highway standard. Later on different alternatives were searched and finally 50m long bridge restored in short period of 4 to 5 month as a mid term solution. The article shall enlighten about the engineering judgement and decisioning sequences to meet the target.
Importance:
E-W highway, still plays the backbone role for national transportation system of country. Kamala-Pathlaiya section of highway is not only the important link of it but also lifeline for connectivity of all transportation section in Madhesh Province yet. Most of the bridge constructed under USSR support during its construction, served the nation since, 19xx. At that time may there be the deficiency of hydrological data and need of mass construction, 60+ bridges were made with pre-cast concrete sections with logical assumptions for hydrology and scour depth calculation. Bhapsi Bridge is one of them located west of Bardibas
E-W Highway is the NH01 rated and first priority road in Nepal and Bardibas a fast growing city, close to Kathmandu and Janakpurdham. Hence the road remains busy with both passenger vehicles and freight movement of different class. The movement is continuously increasing from 5960 in 2017 to 11597 PCU in 2020 after Janakpur city was confirmed as capital city for Madhesh provience. In 2017 Rato Bridge, east of Bardibash settled due to flood of simmilar situation and new pre-stressed bridge was constructed. Again the similar flood situation washed 2 middle spans of Bardibash enforcing people to move through 40Km longer alternative of low standard road. The area is characterized as flash flood zone in rainy season. Hence bridge restoration need to be finished before rainy season repeats again. In either case, traffic diversion was managed with belly bridge.
Accidental Sequence:
The bridge flooded at mid-night on 13th July, 2019 causing disruption of
highway service. A huge number of vehicles have been stuck without
possibility to move ahead. Meanwhile the issue was national headline, team of DRO engineers inspected the situation and Superintending Er Ramhari Pokharel in team with DRO chief Er Devendra Sah diagnosed the site early morning, in search of route cause and immediate alternative option. Immediately after technical team
decided to insert a Modular Panel Belly Bridge for traffic movement. It was installed in hurry-up situation to cover as soon as possible. Mr. Uddhav Shrestha, representing Hulas Steel Industries who had earlier experience in steel work was assigned for the task and the bridge element was imported from emergency storage under DRO Lahan. Finaly, the
network was restored in a week with load restriction. It was a comfortable
situation for months and media appraised the team for immediate relief response
of DoR team.
Maintenance & Operation Issues in Modular Bridge:
The next level problem
begun to alarm, when the belly bridge members were showing sign of crack and
frequent pullout of the nut-bolts. DRO team at that time considered the
case as usual situation and tightened the bolts of loose members number of time and
replaced the minor bracing members.
It was operated in similar situation
when I take the charge of DRO office. During my passage from Birgunj to
Janakpur I noticed something is wrong with the sound of bridge when heavy
vehicles passed through it.
In the same week our team inspected the site and
reported the crack symptoms in bottom chord of middle modular panel at four corner around quarter span. It
was immediately reported to FRSMO Superintending Er. Shiva Raj Adhikari and again repaired by calling
same initial team involved in initial assemblage of modular bridge, as he recommended. The problem repeated with major cracks on one side and we requested him for field verification. Meanwhile the crack progressed on 3 of 4 corners at quarter span and was almost daily verified by DRO staffs. We finally decided to weld the brokage with gusseted plates. But still, the crack resumed on all side. Finally we examined all members, the still parts were looking okay. The problem was due to heavy loaded truck, especially when they apply break on bridge the middle span can deflect but there was heavy impact on the edge of quarter span. The belly bridge should have been raised enough to allow deflection. We noticed that the bottom member of middle panel was resting on Kerb of old bridge, causing severe impact to break the members again and again. After understanding the failure mechanism, we raised the members with hydraulic jack and dismantled all side Kerb block touching the bottom chord. Later on the impact sound reduced, now the deflection was allowed. We finalized again by tightening nut-bolts and welded broken members properly attaching gusseted plates. During regular inspection we corrected approach to cause no impact, for a month the belly bridge was performing well and no additional symptoms appeared. We were hopeful, the bridge be okay to use for few years.
Dissatisfaction Notification:
Although the bridge was open to traffic, due to heavy traffic volume on peak hours vehicles need to queue occasionally & was managed by traffic police. There was frequent complain by engineering collogue and VIP travelling through the bridge regarding reduction in Level of Service for the national highway. DIG office also mentioned the same few times and requested to resolve the issue as soon as possible for security response issue. This problem was reported to DG office, from where we were instructed to look for alternates if any.
Option Search and alternatives:
After instruction from DG Sir, we were preparing for new bridge construction however for that diversion was mandatory to be relocated and the cost of diversion management was calculated to be 3.5 Crores. Stil the LoS be simillar till the new bridge is finalised. The option seased spe the road section Kamala-Pathlaiya is likely to be upgraded to Sixlane standard soon.
New Bridge Construction:
Use of Fallen Down Member:
Independent Discussion with Expert Panels:
Pier Jacketing:
Foundation Issue:
Finalization among Option:
Contract Out with duration Crash:
Contract Clause & Management:
Actual Construction:
Budget Issue:
Finalization:
Conclusive Remarks:
The bridge flooded at mid-night on 13th July, 2019 causing disruption of
highway service. A huge number of vehicles have been stuck without
possibility to move ahead. Meanwhile the issue was national headline, team of DRO engineers inspected the situation and Superintending Er Ramhari Pokharel in team with DRO chief Er Devendra Sah diagnosed the site early morning, in search of route cause and immediate alternative option. Immediately after technical team
decided to insert a Modular Panel Belly Bridge for traffic movement. It was installed in hurry-up situation to cover as soon as possible. Mr. Uddhav Shrestha, representing Hulas Steel Industries who had earlier experience in steel work was assigned for the task and the bridge element was imported from emergency storage under DRO Lahan. Finaly, the
network was restored in a week with load restriction. It was a comfortable
situation for months and media appraised the team for immediate relief response
of DoR team.
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begun to alarm, when the belly bridge members were showing sign of crack and
frequent pullout of the nut-bolts. DRO team at that time considered the
case as usual situation and tightened the bolts of loose members number of time and
replaced the minor bracing members. 
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