Research on Initiation Technology of Small And Medium Radius Extended Shield in Spheroidal Weathering Mass

With our country's strong promotion of green transportation travel, the construction of urban rail transit projects is more and more, in which the tunnel stoic construction of underground projects is more and more extensive, due to the complexity and variety of formations throughed by urban rail transit, the challenge of using the shield construction method is growing. In this paper, how to dig in the construction of shield machine safely and smoothly in the highly developed lonestone group, how to make the extended shield shield body run smoothly with a small radius of 325m cutting line. Summarize the problems that arise in the process of origination and the measures to deal with them in advance, so as to provide reference for similar projects in the future.