ALPINE attains tunnel breakthrough in New Delhi Metro
Alpine, FCC's Austrian subsidiary, has successfully attained final breakthrough of the first section of tunnel linking the city of New Delhi and the airport, under a contract awarded in September 2007. The contract is worth 139.3 million euro.
Digging conditions were very difficult, and Alpine used three tunnel boring machines (TBM) in the project. Tunneling work was conducted at depths of 35-45 metres, with a longitudinal gradient of 2.85%.Moreover, the tunnelling site was located directly below New Delhi's major traffic arteries, such as the Minto Railroad Bridge, Connaught Square and Connaught Circle as well as two existing Metro lines, whose continuous operation could not be disrupted.