中文摘要：

为了对全框式副车架侧边纵梁结构进行耐撞性优化设计，以副车架侧边纵梁结构参数为变量，建立了该结构耐撞性和轻量化优化问题的数学模型。运用方差分析法（ANOVA）选择对副车架侧边纵梁耐撞性和轻量化影响显著的结构因子作为主要设计变量，采用正交试验设计方法进行试验设计；运用LS—dyna软件进行碰撞模拟；根据有限元仿真结果建立了响应面近似模型，并对该近似模型解决该问题的可靠性进行了验证，结果表明，所建立的响应面近似模型适合解决组合优化问题。优化设计后的副车架侧边纵梁能在提高耐撞性能的同时，保持较好的轻量化水平。

英文摘要：

In order to optimize design of a whole box-type sub-frame side rails in terms of structur- al parameters to meet the requirements for light weight and crashworthiness in front impact,an opti- mization mathematical model was established in terms of design variables of the sub frame side rails. First, analysis of variance was carried out to choose the factors that had significant influences on the light weight and crashworthiness of sub-frame side rails as the main design variables. Secondly, a de- sign test was conducted by using orthogonal experimental design method. Then, the Ls-dyna program was utilized for crash simulations. A response surface approximation model was built up according to the simulation results, and the approximate model was validated to solve the reliability problem. The results show that the model established by the response surface is suitable for solving the combined optimization problem in this study. The optimized sub-frame side rails can improve crashworthiness uerformance while maintain a good light-weight level.