Abstract：
With rapid urbanization, more and more subways are built to solve the problem of congested traffic. It is very important to speed up construction progress, reduce cost and ensure construction safety, especially for large-span tunnels in soft rock. The five-step method was first utilized in the construction of the Majiayan Tunnel for the large IVb section of the Chongqing Light Rail Line 1. In this paper, the principles and main construction methods of the five-step method are presented in detail. With this method, the construction period is shortened by 5 months and costs are cut by more than ￥2.6 million.
2011, Vol. 48 