Sectional optimization of plate and shell structures with stress and displacement constraints
应力和位移约束下的板壳结构截面优化

Combining optimality criteria method and mathematical programming, the optimization model is founded to satisfy the stress and displacement constraints. The stress constraint is transformed into movable sectional lower limits with the full stress criterion and the displacement constraint is transformed into an approximate explicitly function of design variables with the unit virtual load method. To resolve large-scale optimization problem with multiple design variables, the model with thousands of design variables is transformed into dual model with several design variables and solved with quadratic programming. With MSC/Nastran software as structural analysis solver and MSC/Patran software as developing platform, the sectional optimization software of plate and shell structures is accomplished. The program is completely in harmony with Patran and Nastran. The model is established with Patran and analyzed with Nastran, the design variables are modified according to the optimization results and then the model is reanalyze with Nastran. Repeating like this until the structural weight is convergent. The examples show the program is reasonable and effective, can meet requirement of engineering application.