CMRL Builds Corridor 5 Viaduct Through Adambakkam MRTS Station Roof

Chennai Metro Rail Limited (CMRL) has constructed its Phase 2 Corridor 5 line directly through the roof of the Adambakkam MRTS station near Velachery, positioning metro tracks perpendicularly nearly 20 metres above the ground.

The alignment decision was chosen to avoid disturbing residential properties in the locality, according to T. Archunan, Director (Projects) at CMRL. Archunan explained that constructing the corridor completely above the MRTS station would have resulted in significantly higher construction costs and made both the viaduct and the subsequent Phase 2 station at Vanuvampet substantially taller.

To carry out the project, workers dismantled a small portion of the Adambakkam MRTS station roof and its overhead equipment line. After removing vertical columns and the station's parapet wall, teams installed temporary beams and steel I-girders block by block. Deck slabs were then constructed for the CMRL tracks before the roof structure was rebuilt.

The construction began last year and continued for three months. Before starting work, CMRL secured approval from the Commissioner of Railway Safety because metro trains will operate directly above the overhead lines of the MRTS network.

CMRL deployed a 56-metre steel I-girder curve section over the MRTS track, making it the first metro system in India to use steel composite girders on curves. Steel girders were necessary because using concrete over the existing railway line at that location was not feasible.

This section of the line was built before the commissioning of the MRTS extension line from St. Thomas Mount to Velachery via Adambakkam. Corridor 5 connects Madhavaram to Sholinganallur, passing over the cloverleaf flyover and Phase 1 corridor at Alandur, through Railway Station Road, St. Thomas Mount, Adambakkam, Ullagaram, Madipakkam, Kovilambakkam, Medavakkam, and Perumbakkam.