基于有限元的永临结合大直径盾构工作井施工过程受力变形分析

Analysis on the Stress and Deformation of Permanent Temporary Combined Large-diameter Shield Working Shaft During Construction Based on Finite Element Method

某高速铁路盾构隧道工程项目盾构管片外径为13.8 m,盾构机外径达14.3 m。文章以该大盾构隧道接收工作井为研究对象,通过有限元建模,模拟永临结合大盾构工作井结构体系在施工过程中各工况下的变形、受力情况。模拟结果显示,在破除环框梁时,侧墙变形显著增大,盾构孔处环框梁受力显著增大,需重点设计;对于大跨度洞门,当采用玻璃纤维筋地下连续墙时,需加强洞门范围内地连墙的水平钢筋布置。

The outside diameter of shield segment of a highspeed railway shield tunnel engineering project is 13.8 m,and the outside diameter of shield machine is 14.3 m.This paper takes the receiving working shaft of this large shield tunnel as the research object,and simulates the deformation and stress of the structural system of the permanent and temporary combined large shield working shaft under various working conditions during the construction process through finite element modeling.The simulation results show that when the ring frame beam is broken,the deformation of the side wall increases significantly,and the stress of the ring frame beam at the shield hole increases significantly,which needs to be designed emphatically;for the large-span portal,when the glass fiber reinforced diaphragm is used,it is necessary to strengthen the horizontal reinforcement arrangement of the diaphragm wall in the portal area.