Delhi Metro Rail Corporation Ltd. (DMRC) began work to scoop out the tarred layer of the crack-ridden Palarivattom flyover on Monday morning, prior to reconstructing its pier caps, girders and deck.
A pooja was conducted prior to beginning the work. Sources in Uralungal Labour Contract Cooperative Society (ULCCS), to which DMRC entrusted the work, said that the entire tarred surface of the four-lane structure located on the Edappally-Aroor NH bypass would be scooped out in three days. The material will be taken to DMRC’s concrete pre-casting yard at Muttom, for possible reuse.
This will be followed by work to cut the concrete structure into pieces, using diamond cutters. The cut pieces will be brought down using crane and crushed beneath the flyover, while taking care to prevent dust from affecting motorists and others passing through the junction. Simultaneously, steel will be extracted from the concrete, as was done with the debris of apartments that were demolished at Maradu, for recycling. The crushed concrete material too would most likely be taken to the yard, they added.
Sea-wall plan dropped
The proposal to slice the concrete into specific shapes for being used as sea wall in Chellanam and other coastal areas severely affected by raging seas, has been dropped. This is because lorries cannot negotiate through the area, it is learnt.
It might take up to four months to dismantle the pier caps, girders and deck of the four-lane structure. Reconstruction work, scheduled to take up to nine months, will be done simultaneously. A total of ₹18 crore is estimated to be the cost to dismantle and rebuild the structure. Piers (pillars) will not be touched, since they are strong enough. They would be strengthened using concrete jacketing, sources said.
Sources in DMRC reiterated that the impending reconstruction-cum-reinforcement work would ensure that the flyover had a 100-year life span. This is in contrast with less than 20-years life, if it were to be strengthened through carbon-fibre wrapping.
Over 2,000 cracks
The flyover, built by Roads and Bridges Development Corporation of Kerala Limited (RBDCK) and commissioned in 2016, was closed to traffic in May 2019 after over 2,000 cracks, small and big, were detected on its girders and pier caps. The nine-month reconstruction work was entrusted by the State government to DMRC in the third quarter of 2019 and work was set to begin from October 1, 2019. The year-long delay occurred after contractors and allied bodies approached the High Court, seeking conduct of a load test to determine the flyover’s strength.
The government decided to go ahead with the reconstruction of the crack-ridden parts of the structure, after the Supreme Court permitted it a week ago to go by the decision of expert committees which had been set up to probe the flyover’s structural strength. The committees, including the one headed by Metroman E. Sreedharan, had recommended reconstruction of the structure, with the pillars remaining intact.
