The Thomson Line of the MRT is a complete underground system connecting the north of Singapore to the south. It has a total length of 30km long and consists of 22 stations. The construction is divided into three stages commencing public operations in 2019.
Contract 2102 covers the stations of Woodlands North, Woodlands, and Woodlands South. Woodlands North is an open cut 13-15m depth slope excavation consisting of drains to allow water drawdown. Woodlands station is a Civil Defence and interchange station connecting to the North-South Line. Woodlands South Station is constructed with a top-down method and needs 20-25m excavation supported by SBP walls, slab, struts king posts and waler beams.
Contract 2103 consists of 8 stations with a total of 14.5km from Springleaf Station to Mount Pleasant Station. All ERSS system is checked for toe stability and base heave check according to BS 8002. Plaxis.v10 is used for FEM analysis for excavation. Permanent structures are designed to satisfy the LTA Civil Design Criteria, including the permanent wall and the effect of the blast.