当盾构在软土地区开挖时,在由施工扰动引起的地面沉降中,固结沉降占到很大比例,所以盾构施工时产生的超孔隙水压的分布规律必须加以研究和认识.利用比奥固结方程和热传导方程的相似性,采用有限元计算软件ANSYS的热分析模块来分析固结,得到了盾构施工时周边土体超孔隙水压的分布和消散规律,在此基础上,应用ANSYS应力分析模块,进一步计算分析盾构施工引起的固结沉降.
When shield tunnel is excavated in soft soil area,the consolidation settlement accounts for a very high proportion of the overall settlement induced by tunnel, so the excess pore water pressure distribution must be researched during excava tion.In this paper,based on the similarity between the Biot consolidation equa tion and heat conduction equation,a simple method is proposed using thermal con duction module in ANSYS software to calculate the excess pore water pressure aro und the shield tunnel.By this method,the distribution characteristics of the e xcess pore water are acquired in the vicinity of the tunnel.On the basis of res earch above,the consolidation settlement is further evaluated by ANSYS fu nction of stress field analysis.