The multi-objective structural optimisation design to improve the crashworthiness of a multi-cell structure for high-speed train

This article addresses the energy absorption and crashworthiness optimisation of a multi-cell energy-absorbing structure which is composed of orthohexagonal tubes and connecting column under dynamic impact loading. In this work, a finite element model was established and effectively verified using experimental data. To explore the effects of each structural part length parameters on crashworthiness characteristics such as the specific energy absorption (SEA) and the impacting force efficiency (IFE). The influence of design variables on the impact response is evaluated based on the parametric study of surrogate model. The results show that side lengths at different locations have different effects on SEA and IFE. The characteristics and trends of different variables are different. In addition, based on the surrogate models, to maximise the SEA and IFE under the constraint of design space, multi-objective optimisation design was carried out using multi-objective genetic algorithm. The optimised structure has significant improvement in SEA, IFE and space.