以车体钢结构重量最轻为目标,以梁截面和梁位置拓扑为设计变量,应力、位移为约束条件,建立了优化模型.以MSC.Marc软件作为分析器,将其中的生死单元技术与遗传算法的思想有机的结合起来,建立了一种研究结构拓扑优化的新方案,编制了计算程序系统.并应用此系统对某车体钢结构进行优化设计,取得了成功,充分证明了该系统的正确性和实用性. Taking the lightest weight of the steel body of the vehicle as the target, the beam cross-section and topological position of the beam are used as the design variables, and the stress and displacement are constrained to establish the optimization model.With the MSC.Marc software as the analyzer, The idea of ​​genetic algorithm is combined organically to establish a new scheme to study the topological optimization of structures and to develop a calculation program system.Optimization design of a steel structure of a vehicle body is made with this system and it is proved that the system Correctness and practicability