关键词: 直线积分边界元法;降维;域积分;热应力;

Abstract: As a semi-analytical method, boundary element method (BEM) has the advantage of dimension reduction, which means this method only need to disperse the boundary for the research field. However, when it comes to solving the thermo-elastic problems, the domain integral will appear in the boundary integral equations. In order to ensure the advantage of BEM, the line integration method (LIM) is used to transform the domain integral into the boundary integral based on the divergence theorem. The boundary integral can be calculated by the boundary element with integral points. An integral line can be constructed for each integral point, and the domain integral can be calculated by the line integral on the integral line. In order to obtain higher accuracy, the integral line can be cut into sub-lines by using the background cell. This method’ feasibility and accuracy is proved by a thermal-elastic analysis of a rectangular beam and thermal stress analysis of a gravity dam.

Key words: line integration boundary element method; dimension reduction; domain integrals; thermal stress