软土地区盾构隧道变形及加固分析

Analysis of the Deformation and Strengthening Effect of Shield Tunnel in Soft Soil

以上海某地铁区间为工程背景,建立三维盾构隧道环,分析了其在软土中的接头张开和变形发展规律。并开展了钢板加固隧道的分析,探讨了加固效果和变形行为。研究表明:在软土中盾构隧道变形主要呈"横鸭蛋"形,随上覆土荷载增大,隧道腰部处接头张开速度快于顶部接头;软土中的隧道采用钢板加固具有良好的效果,当上部覆土荷载不大于600kPa时,加固后隧道接头张开量降低60%,隧道变形降低50%。

A three-dimensional shield tunnel ring was established, based on the background of a subway engineering in Shanghai. The development of joint opening, deformation of the tunnel in soft soil are analyzed. And the strengthening effect of the steel plate was discussed. The results show that the deformation of shield tunnel in soft soil is similar to a "horizontal duck egg", and the development of the joint opening increasing at the tunnel waist was faster than that at the top with the overlying soil load increasing;the strengthening effect of steel plate is satisfied, the joint opening and deformation can be reduced by 60% and 50%, respectively.