ABSTRACT
This paper describes multiple challenges encountered during construction of a 6.5 km long underground metro line with 6 stations in the highly congested Old Surat City (Gujarat, India) with narrow lanes and the site-specific solutions adopted to execute the same successfully. The main challenges include adjusting underground station in 14 m width, ensuring safe excavation up to 41 m depth within 2 m of a century old buildings and three century old Heritage structures in a poor structural condition and diversion of major wet utilities with no space for accommodating in the station area. The paper also describes a case of main bearing failure of TBM below buildings and the special measures taken to drive the TBM to reach a safe location for bearing replacement. Another case presented is of replacing a damaged TBM cutter head at lower platform level of stacked station while allowing movement of muck trolley/segment car for other TBM at upper platform level in the same shaft by constructing a bridge structure.
