TBM COMPLETES THIRD BORE FOR CHENNAI METRO PROJECT

摘要

On 31 October a 6.65m diameter Robbins EPBM broke through at Chennai Metro, making this the third tunnel the machine has bored for the project and for contractor Afcons Infrastructure. After completing its original twin tunnels, the EPB was refurbished in preparation to bore its latest 1.8km section. During refurbishment, the inner seal greasing system was changed from auto to manual mode and the foam nozzle system was modified. These changes optimised the machine for excavation in the highly variable mixed face conditions encountered in the first two tunnels.