Abstract:

Serious settlement, convergence and deformation always occur during the construction of doubletrack railway tunnels located in soft ground. 3bench 7step construction method, CRD construction method and enlargedarchfoot bench method are adopted in the construction of Liangshui tunnel on LanzhouChongqing railway. These three construction methods are compared in terms of safety, advance rates and equipment availability. It is concluded that enlargedarchfoot bench method is more suitable for the construction of doubletrack railway tunnels located in soft ground.

Key words: tunnel in soft ground, deformation control, monitoring, enlarged arch foot bench method