BENGALURU : In a first, a U-girder was launched by Bangalore Metro Rail Corporation Limited (BMRCL) in the early hours of Sunday at Doddanekkundi. Girders are the sturdy, horizontal structures placed above the pillars, on which rails are laid for operation of trains.
U-girders can be erected quicker and involve economy of design rather than those used in Metro’s Phase-I. The girders will be laid on both Phase-2A (Central Silk Board to KR Puram) and Phase-2B (KR Puram to Airport) lines, totally running to 58.19km.
A top Metro official told TNIE that the girder, running 28 metres, was readied at a yard in Hoskote by Shankar Narayana Constructions, and brought to Doddanekkundi late Saturday night using a special trailer. “It was erected post midnight. Erection of a span (28-m block between two pillars) usually takes us anywhere between 6 and 8 days in the traditional method. However, using U-girder technology, we can complete one span in three hours,” he said.
Two cranes, one that could carry a maximum weight of 700 tonnes and another that could carry up to 400 tonnes, were used to lift and place the girder. Around 1,600 U-girders will be laid along the two lines and it could take between 1.5 to 2 years for work to be completed, the official said.