重力坝分析的改进有限元等效应力法

Study and application of the improved finite element equivalent stress method to analyze the strength of gravity dams

本文提出了重力坝分析的改进有限元等效应力法,分析了改进前后应力计算结果的变化,研究表明,当网格尺寸较大时,改进的等效应力方法具有更高的精度。对比研究了采用有限元等效应力方法、材料力学方法计算应力在结果上的相同点和不同点。分析表明,有限元等效应力法在解决应力集中的同时,还能反映地基刚度对建基面竖向正应力分布的影响,从而解决了材料力学的一些限制。结合我国第一座胶结颗粒料永久工程—守口堡工程的设计,详细分析了地基刚度对坝基面应力分布的影响,取得了很好效果。

The improved finite element equivalent stress method is proposed and studied in this paper. It is proved that higher accuracy is acquired through the improved method, especially when the size of FEM model is large. The difference and similarity of results derived from conventional finite element equivalent stress method, material mechanical method and the improved finite element equivalent stress method are an- alyzed. Results show that the improved finite element equivalent stress method can avoid stress concentra- tion, and it also can better reflect the influence of base stiffness on the equivalent stress. The application to the equivalent stress analysis of Shoukoubao CSG dam, the first CSG dam in China, gets quite satisfactory results.