A crashworthiness optimization method of subway underframe structures based on the differential evolution of the weighted graph representation

The crashworthiness optimization of the subway end structure is essentially a topology–shape–size collaborative optimization problem of a composite structure under collision conditions. To this end, a rapid multivariate co-optimization method based on weighted graph model and differential evolution algorithm is proposed. The underframe configuration is mapped as a weighted graph and then represented by mathematical matrices. By parameter inversion, a basic parametric simplified finite element model is established and validated by the detailed finite element model and the impact test. Three different configuration optimizations are accomplished and compared to prove the efficiency of the proposed method. The research results of this paper provide a reliable method and a reference for the further development of the crashworthiness optimization for complex structures.