Lovat Launches TBM in SingaporeDowner Engineering has launched a refurbished 6.15 m-diameter Lovat TBM, model RMP242SE Series 18500, for the Singapore cable tunnel contract C302, section from West Coast Park vent shaft to Labrador vent shaft. The RMP242SE will negotiate multiple 130 m radius curves, tunnelling a total length of 2.65 km and installing a prefabricated reinforced concrete segmental lining, consisting of five segments and one key segment. The lining will have an outside diameter of 5.9 m, an inside diameter of 5.4m and each ring is 1.2 m in length. As of early week 17, the TBM had installed ten rings. Segment erection times is well within contract specifications.The tunnel alignment is generally from northwest to southeast. The bored tunnel begins at the Harbour Drive equipment building and ends at the Labrador ventilation shaft. The tunnel section from West Coast Park vent shaft to Harbour Drive equipment building is cut-and-cover. It will be constructed through the Jurong formation as well as recent alluvial deposits. The Jurong formation consists of sandstone, mudstone and siltstone with varying degrees of weathering. The entire tunnel alignment is being constructed beneath the ground water table. The ground water in the area of the tunnel is typically at or about elevation 101 m. The tunnel invert elevation varies from a height of 81 m to a low of 63 m. This allows for a maximum ground water pressure above invert of up to 3.7 bar. Visit www.lovat.com 19/04.