Construction on the Hsinchuang line of the Taipei MRT got under way at the end of July and looks set to involve Taiwan’s most challenging tunnelling to date.
Seven contracts make up the extension, which winds 19.7km from Huilung station in the western suburbs, to Kuting in the centre.
Construction on contract 570C began on 22 July, which will include a 3.2km twin bore tunnel 41m below the Tamshui river. Engineers will have to balance the tunnels’ great depth with high pressure and a wide shield diameter – 6.24m. Ground-freezing and extensive grouting, will control water ingress and help prevent the face from collapsing. Tunnelling is due to start in August 2004, with completion envisaged in April 2007.
RSEA/Kajima/Huang Chang JV is the contractor on the US$222 M 570C, with the cost of tunnelling US$39M. As with all the contracts that make up the Hsinchuang extension, the TBMs have not been chosen, but they are expected to be 6.24m diameter, to produce the 5.6m i.d tunnels.
The rest of the 19.7km extension is split into six other contracts.
570A: BES Eng. Corp/ DaiHo Corp JV; July 2002-Feb 2007; tunnel cost – US$12.2M out of US$58.6M.
570B: Dacin Construction Corp; Aug 2004-Oct 2006; tunnel cost – US$36.6M out of US$149.8M.
570D: BES Eng. Corp/ DaiHo Corp JV; Aug 2003-July 2006; tunnel cost – US$41.3M out of US$131.9M.
570E: RSEA/Kajima JV; March 2004-July 2006; tunnel cost – US$44.8M out of US$134.7M.
570F (NATM): Kung Sing Eng. Corp; completion Oct 2007; tunnel cost – US$6.6M out of US$44.4M.
570G: RSEA Eng Corp/ Okumura Corp JV; April 2004-Aug 2006; tunnel cost – US$8.2M out of US$57M.