提出一种间接测量平面接触刚度的方法，准确量化粗糙表面的接触刚度，使得整个支架系统的固有频率模拟与测试结果得到良好的匹配。基于接触刚度模型、ANSYS有限元模拟方法以及模态测试方法，以地脚螺栓固定方式的测试件为例，验证了间接测量方法的准确性，使接触刚度得到准确量化。该方法可以为提高加速器磁铁支架系统的整体刚度提供依据。

In the simulation of the accelerator magnet support system, the parts connected to the ground by the magnet bracket are usually treated as “fixed”, but in some cases, this treatment will cause a large error between the simulation results and the measurement results. This paper proposes an indirect method to measure the contact stiffness of rough surface, accurately quantify the contact stiffness of rough surface, and make the simulation of the whole system well match with the test results. Based on the contact stiffness model, ANSYS finite element simulation method and modal test method, the accuracy of indirect measurement method was verified by taking the test piece of anchor bolt fixation method as an example, so that the contact stiffness was accurately quantified. This method can also provide a basis for improving the overall stiffness of the accelerator magnet support system.