基于XFEM的重力坝裂缝扩展路径的探讨

近年来,扩展有限元法被广泛用于处理不连续问题,因该方法克服了常规有限元法在模拟裂缝扩展时需不断的网格重划分及对裂纹面与单元边界一致性的要求而导致的繁琐计算和误差等缺点.用二维扩展有限元法模拟了带水平缝混凝土重力坝在水压作用下裂缝的扩展路径.首先,讨论了裂缝扩展增量对其路径的影响,然后研究了裂缝在不同高度和初始长度下的扩展路径.结果发现扩展增量对裂缝扩展路径方向影响甚微,但对大坝的位移影响较大;裂缝的高度和长度对其扩展路径影响均不大.

Study of Control Parameters of Concrete Cracking Growth with XFEM

In recent years, XFEM is widely used to treat problems with discontinuities for suppressing the need to mesh and remesh the discontinuity surfaces, thus alleviating the computational costs and projection errors associated with conventional finite element methods, at the cost of restricting the discontinuities to mesh edges. The crack propagation path of concrete gravity dam with horizontal crack under water pressure, which was simulated using two-dimensional XFEM, was investigated. Firstly, the influence of incremental value on crack propagation path is discussed. Then the crack propagation path is studied by varying the height and initial length of crack. The results show that incremental value has little impact on the crack propagation direction but larger impact on the dam displacement; and both the influences of crack height and length on crack propagation are quite small.