基于接触表面非均匀压强分布的栓接结合部动力学模型

针对栓接结合部在多螺栓耦合作用下接触表面压强不均匀分布的特点，提出基于接触表面非均匀压强分布的栓接结合部动力学模型。假设栓接接触表面在宏观尺度上为平滑表面，基于有限元方法获得表面压强分布规律。栓接表面微观尺度上为粗糙表面，采用分形接触理论，建立基于表面接触压强的栓接结合部法向和切向刚度阻尼模型。构建框型栓接结构件实验装置，并通过模态测试获得栓接结构件在不同预紧力下的固有频率和频响函数。与仿真结果进行对比，所提出的模型能够准确描述栓接结合部动态特性。

Dynamics Model of Bolted Joint Based on Uneven Pressure Distribution of the Surface

In this paper, a dynamics model based on the surface uneven pressure distribution was presented for the bolted joint because the surface contact pressure of bolted joint is uneven distribution due to the influence of concentrated force of multi-bolts. The contact surface of bolted joint was assumed to be flat in macro-scale and the pressure distribution can be obtained by the FEM. The contact surface of bolted joint was rough surface in micro-scale, and the normal and tangential stiffness damping model based on the surface contact pressure was presented for the bolted joint using fractal contact theory. An experimental set-up with box shape specimen was designed for validating the presented model. The natural frequencies and frequency-response function can be obtained by modal testing. Compared with simulation result, the presented model can be used to accurately predict the dynamic characteristic of bolted joint.