Kottayam: After a day-long bid to raze an railway overbridge in the heart of Kottayam town through a remote-controlled demolition failed late last month, authorities are planning to use another method to demolish it. They have decided to cut the structure into pieces, which would then be lifted and shifted with a crane. The next bid to demolish the bridge located at Nagampadom could be taken up next month.
An expert team had inspected the bridge and given its clearance for the new plan. Railway authorities said that this plan was adopted after another idea to push down the 305-tonne bridge was not found feasible.
As per the latest decision, the bridge will initially be strengthened by fixing large steel pipes below. Afterwards, the structure would be cut into several portions using concrete cutters. The next step involves shifting the pieces of the bridge with the help of a crane.
It is estimated that 22 hours would be need to complete this task. Even though the Railways has allotted 24 hours to demolish the bridge, the Railway Engineering Wing officials said that the work would be over in lesser time. Still, train traffic would be blocked for 24 hours. Earlier, traffic had been suspended for 9 hours to carry out the explosions.
Under the new plan, the railway tracks risk no damage. However, the overhead electric lines need to be entirely removed and train traffic through Kottayam railway station would have to be fully suspended for one whole day.
The new effort to cut the bridge and lift the pieces was considered after two attempts to demolish the structure with controlled explosions failed.
A total of 1,200 holes were drilled and explosives stuffed ahead of the demolition bid. Only 12 detonators out of 1,200 went off. Initial analysis had found improper circuitry led to the failure.
The problem was with the detonators and demolition contractor (Maclink Infra Projects from Tirupur), the Railways said. Experts had analysed the detonators after the explosives were removed.
Renowned engineer E Sreedharan had then claimed that it would be difficult to bring down the bridge as it is exceptionally strong.
Sreedharan was the assistant engineer at Kottayam railway station when the overbridge was being built in 1955.