深厚覆盖层上土石围堰的应力变形研究

Study on Stress and Deformation of Earth-Rock Cofferdam on Deep Overburden

以修建于深厚覆盖层上的土石围堰为研究对象,利用有限元软件ANSYS分步模拟堰体填筑和大坝基坑开挖过程。重点研究围堰竣工及基坑开挖的过程中堰体与混凝土防渗墙的应力变形特征。计算结果表明:整个施工过程中堰体与防渗墙沿三个坐标轴方向的位移分布规律良好,数值均在变形合理范围内,且各应力特征值均未超过设计标准,该围堰与防渗墙从施工期到运行期都是安全稳定的。

This paper takes the earth-rock cofferdam on the deep overburden as its main study object and numerically simulates the cofferdam filling and dam excavation process using FEM software ANSYS. The research is mainly focused on the stress and deformation characteristic of the cofferdam and concrete cutoff wall during completion and excavation proce- sses. The results show that displacements of the cofferdam and cutoff wall are well distributed in three coordinate axes during the entire construction with all the values within the acceptable dis-formation limit and stress characteristic values not exceed- ing the design standard, and the cofferdam and cutoff wall are safe and stable both in construction period and operation period.