Abstract: The chassis system is the main load-bearing path of the entire vehicle and an important part of the durability and reliability development. This article aims to establish a comprehensive research method for the generation mechanism, test verification methods, and optimization strategies of durability and reliability problems in automotive chassis systems. This method integrates finite element analysis (FEA), fatigue life prediction, and multi-axis road simulation bench tests for damage equivalence. Through multi-body dynamics simulation analysis based on measured load spectra, the loads on key chassis components are obtained. By using FEA and fatigue life prediction, typical failure problems of the rear subframe are revealed. At the same time, structural optimization analysis is employed to propose solutions to the problems, and the effectiveness of the solutions is verified through multi-axis road simulation bench tests. A case study of a sport utility vehicle (SUV) model is further used to validate the method. The results show that the improvement plan based on structural optimization and material upgrading for the rear subframe is effective, and the fatigue life of the optimized chassis system has increased by 42%, verifying the engineering effectiveness of the method.

Key words: durability; damage equivalence; subframe; fatigue life

摘要： 底盘系统是整车主要的承载路径和耐久可靠性开发的重要环节，文章旨在构建一种汽 车底盘系统耐久可靠性问题的产生机理、测试验证方法与优化策略的综合研究方法。该方法 融合了有限元分析（FEA）、疲劳寿命预测与损伤等效的多轴道路模拟台架试验，通过基于实 测载荷谱的多体动力学仿真分析，获得底盘关键部件的载荷，借助有限元分析和疲劳寿命预 测并揭示后副车架典型失效问题，同时运用结构优化分析提出解决问题的优化方案，通过多 轴道路模拟台架试验验证方案的有效性。结合某运动型多用途汽车（SUV）车型开发案例进 一步验证，结果表明，后副车基于结构优化与材料升级的提升方案是有效的，优化后的底盘 系统疲劳寿命提升了 42%，验证了方法的工程有效性。

关键词: 耐久性；损伤等效；副车架；疲劳寿命