ABSTRACT
This paper presents the challenges encountered in the construction of the twin 2.0Km, 12.2m diameter undersea Coast Road Tunnel. Construction of the Coast Road tunnel was unique in many respects as it extended the barriers previously undertaken in India’s Tunneling industry. The TBM, “Mavala”, named after a Maratha warrior, is currently India’s largest and the Coast Road tunnel therefore India’s largest TBM constructed tunnel. Additionally, the tunnel is India’s first undersea tunnel and when commissioned its design will embrace all current International Highway Design and Operational Standards which include many unique Fire and Life Safety systems including what is believed to be the world’s first Bi-directional Saccardo Ventilation system. The paper presents some of the many challenges in achieving these unique Indian firsts.
