首先导出了包含根部挠性参数的悬臂梁动力学方程近似解,将平动和转动柔性参数作为不确定性源,根据若干预紧力矩下的模态实验结果完成了柔性参数识别,并假定其服从正态随机分布,识别了均值与标准差,进而通过回归分析建立了不确定参数随预紧力矩变化的数学模型.最后通过新的模态实验结果对所建模型进行了确认,通过确认结果,明确了该模型的使用范围.
There are some flexibility and uncertainty in the root of a cantilever with bolt joints. The dynamic equation and the approximate result of the cantilever with flexible parameters are presented in the paper. At the same time, in order to study the uncertainty modeling, the translation and rotation flexible parameters are chosen as the uncertain parameters. Then the flexible parameters are identified according to some modal test results. The mean and standard deviations of flexible parameters are obtained by analyzing the identified results subjected to the normal distribution assumption. The mathematical models of the uncertain parameters varying with the pre-torque are built. The models are validated by other modal test results, and the applicable ranges of the models are obtained according to the results.