Precast method helps Railways complete bridge ahead of schedule

Thanks to technology, SR has completed a bridge and subway construction in record time on the Chennai – Villupuram section, reducing the proposed line block-that otherwise lead to the cancellation of a few local trains on the route-by an hour.

Railway engineers have successfully constructed a major bridge at km 38/11-12 between Guduvanchery and Vandalur on the Chennai Beach – Villupuram section using precast reinforced concrete segments.

The bridge was sanctioned in 2017-18 following a breach at the location in December 2015.

SR had proposed two minor bridges which were completed in 2018. However, the major bridge was an irritant to SR, which split its construction to two weekends to reduce the inconvenience caused to passengers. SR used 12 precast reinforced concrete segments measuring 9.15m x 2.65m (each segment 1.5m wide and weighing 70 tonnes each) that were placed with the assistance of a 350-tonne capacity crane using ‘cut open’ method. Due to the precast method, SR had managed to complete the major bridge work in a record 13 hours, an hour less than the scheduled line block permitted for the work.

SR has also managed to insert temporary girders for the construction of a subway at Level Crossing no 57 at km 66/14-16 between Chengalpattu and Ottivakkam. Meanwhile, the engineers have also put the line block to good use by providing supporting braces for the Foot-over-Bridge under construction at Egmore and undertook 3700 metres of track maintenance between Vandalur and Guduvanchery.

A statement issued by SR said that attention to various track conditions, including water stagnation prone places and greasing, were done in the section along with sleeper renewal wherever required.