基于SBFEM的坝-库水相互作用分析

Analysis of dam-reservoir interaction based on SBFEM

将W o lf和Song提出的比例边界有限元法(sca led boundary fin ite e lem en t m ethod,简称SBFEM)应用于坝-库水相互作用分析.在库水不可压缩假定的前提下推导了坝面动水压力与附加质量矩阵的基本方程.二维重力坝和三维拱坝坝面动水压力的算例表明,与有限元法比较,SBFEM计算精度明显提高,同时由于具有降维的特点,计算工作量也在很大程度上有所节约.还分析了库底和水面坡度变化以及水库边界形状适当变化对动水压力分布和数值大小的影响.结果表明,一般情况下水库边界的变化对动水压力的分布形状基本上不发生影响,对动水压力数值大小也影响不大.

The scaled boundary finite element method （SBFEM） put forward by Wolf and Song is used to study the dam-reservoir interaction problems. Based on the assumption of incompressibility of reservoir water, the basic formulae for calculating hydrodynamic pressure and the added mass matrix are derived. Numerical examples of two-dimensional gravity dam and three-dimensional arch dam have been provided. It is shown that this approach is superior to finite element method in computational efforts and accuracy. The effect of the slope of the reservoir bottom and the water surface, and the slope of the reservoir boundary on the distribution and the magnitude of the hydrodynamic pressure have also been discussed. It is shown that the changes of the boundary have no effect on the distribution and less effect on the magnitude of the hydrodynamic pressure generally.