本文应用模态综合技术的基本理论,将固定界面模态综合法与自由界面模态综合法相结合,推导出适用于求解客车类厢形结构固有特性的计算方法,将该方法编制成计算机程序,并对SX680大客车进行计算.将计算结果与试验结果和用其它方法的计算结果进行了对比,表明该方法具有综合效率高,计算量小,结果精确等优点,为在微机上实现复杂结构的动力计算提供了一种可行方法。 In this paper, the basic theory of modal synthesis technology is applied to combine the fixed interface modal synthesis method with the free-surface modal synthesis method to derive a calculation method suitable for solving the inherent characteristics of passenger car-like structures. The method is compiled into a computer program, And compares the calculation results with the test results and the calculation results by other methods, which shows that the method has the advantages of high comprehensive efficiency, small calculation amount and accurate results. In order to realize the complex structure Power calculation provides a viable method.