利用非耦合的有限单元法分析了三峡工程三期心墙围堰方案中围堰的稳定性和变形情况。由于施工期很短,水下抛填粘土的孔隙水压力只能部分地消散,因而抗剪强度较低。这样无论在施工期和挡水期堰体中都有可能出现通过水下抛填粘土的滑动面。同时所产生的铅直变形也很大。因而水下抛填体需要采取一定的措施才能满足设计的要求。 The uncoupled finite element method is used to analyze the stability and deformation of the cofferdam in the third phase of the Three Gorges Project. Due to the short construction period, the pore water pressure of underwater throw-on clay can only partially dissipate, resulting in lower shear strength. In this way, it is possible that the sliding surface of the clay is thrown underwater by the weir body during the construction period and the water stop period. At the same time the resulting vertical deformation is also great. Therefore, it needs to take certain measures to meet the design requirements.