三峡重力坝三维随机有限元可靠度分析

Reliability Analysis of Three Gorges Gravity Dam by Three Dimensional Random FEM

三峡大坝是长江水利枢纽的重要建筑物之一,本文在考虑上、下游水位、扬压力、材料强度和弹模随机性下,用三维随机有限元对其进行可靠度分析。采用20结点等参单元和15结点三棱柱单元,对于溢流坝段,在利用对称性下,取一半进行分析;其中坝体和坝基分别划分出103和63个单元,总结点数为988个。编出了SRE3程序,在M-360计算机上算出了坝体的点可靠度;并深入研究了施工导流未封孔段周围、泄洪孔周围和坝踵的可靠度。为三峡重力坝枢纽中多层大孔口坝段的安全的评价提供了重要的成果。

Three Gorges gravity dam is one Of the important structures in the hydraulic project.In this paper,the dam is analysed by three dimensional random FEM considering water pressure,seepage and the material properties of the dam and the foundation as random variables.A special program is com- piled for the method and used to obtain the reliability indexs for the points of interest of the dam,espe- cially for the points around the diversion outlet,and flood discharge outlet and the heel of the dam, which are important results for evaluating the safety of the dam.