Milestone for Whitefield metro as Open Web Girder placed above railway track

The BMRCL's plans to provide metro connectivity between Baiyappanahalli and Whitefield received a big boost on Friday with the placement of a 63.22-metre, 550-metric tonne steel Open Web Girder (OWG) across the railway line near Benniganahalli in eastern Bengaluru.

A girder is a support beam used in bridge construction. An OWG is usually used for building elevated railway tracks.

Namma Metro had to use the OWG because its 15.25-km Baiyappanahalli-Whitefield line passes above the Bengaluru-Salem railway track near Benniganahalli. It has constructed viaducts on the rest of the line and completed about 99% of the work.

The absence of the OWG had prevented the running of trial runs between Baiyappanahalli and KR Puram. Namma Metro is currently conducting trial runs between KR Puram and Whitefield, which is expected to open by March.

The OWG placement took a long time to materialise because the South Western Railway (SWR) authorities weren't fully satisfied with the safety measures taken by BMRCL. It was a complex task that required stopping train movements on the line.

The task was finally completed on Friday as train movement was stopped between 10.30 am and 2.30 pm.

The OWG is 11.45 metres wide and 9.65 metres tall. The distance between its bottom and the railway track is 8.45 metres to facilitate train movements, the BMRCL said. Spherical bearings have been used in the OWG, the BMRCL said.

Some work remains to be done.

To facilitate the remaining work, the railways will stop train movements on the track until February 9, between 11 am and 2 pm, said Kusuma Hariprasad, Additional Divisional Railway Manager (ADRM), SWR. No train movements will be affected during the period, she added.

"Since it's a steel OWG, we asked the BMRCL to ensure proper earthing. We deployed our engineers on the ground to monitor the work and ensure safety," she told DH.

The BMRCL has also been asked to fence both sides of the tracks during the work and prevent crowding.

The Baiyappanahali-KR Puram metro line is expected to open by June.