Tunnel construction with Earth Pressure Balance shields and measures to minimize settlements under urban infrastructure in London

摘要

Tunnelling of Section C250 was performed with two EPB shields over a length of 5.3 km in the area of the city of London under London Underground and Network Rail facilities without interrupting operation. The construction ground conditions encountered - London Clay, Woolwich and Readings Beds, the Upnor Formation and Thanet Sands - placed vastly differing requirements on the supporting pressure of the EPB TBMs, conditioning, quantity surveying and volume control of the excavated soil as well as the dewatering measures.