TBM completes complex Bangkok Purple Line crossing

A TERRATEC EPBM has broken through at Sam Yot Station on Bangkok’s MRT Purple Line extension, completing the third of four TERRATEC-bored tunnels through one of the most complex interfaces on the city’s metro network. The 6.39m-diameter machine broke through on 18 June as part of Contract 3 of the 23.6km Tao Poon–Rat Burana Purple Line extension. A second TERRATEC machine is driving the parallel tunnel and is expected to complete the fourth crossing by the end of September. The two EPBMs are constructing 5.7m internal diameter running tunnels between Memorial Bridge and Phan Fa stations for contractor ITD-NWR MRT Joint Venture, which is delivering the tunnel and underground station works for the Mass Rapid Transit Authority of Thailand (MRTA). The most technically significant section is at Sam Yot, where the new Purple Line tunnels cross the existing operational MRT Blue Line Extension within the station box. The machines previously excavated the two Blue Line tunnels through the same location, meaning the latest breakthrough represents the third of four tunnel drives undertaken by the manufacturer’s machines through the station. The Purple Line crossing has been designed to allow excavation without affecting the operational Blue Line tunnels below. The twin Purple Line drives are independent and do not cross each other. Contract 3 comprises 3.12km of twin-bore tunnel, Sam Yot and Memorial Bridge underground stations and three intervention shafts. Following Sam Yot, the TBMs will continue towards Phan Fa Station, with both drives expected to finish in late 2026 or early 2027. Elsewhere on the alignment, the tunnels will pass beneath the Chao Phraya River near Phra Pokklao Bridge, where cover between the tunnel crown and riverbed will exceed one tunnel diameter, at more than 6.5m. Terratec Incorporated 30 years ago, TERRATEC is one of the world’s leading designers and manufacturers of Tunnel Boring Machines, encompassing all... More Information | [email protected] | +852 3169 3660 Comments: