结合面法向接触阻尼能量耗散弹塑性分形模型

Elastoplastic Fractal Model for Normal Contact Damping Energy Dissipation of Joint Surface

结合面法向接触阻尼能量耗散建模时,只考虑微凸体弹性变形时的储能和塑性变形时的耗能是不完全的,因为微凸体存在弹塑性变形情况。通过引入微凸体加卸载模型,分离了处于弹塑性变形的微凸体的能量储存与耗散,建立了更加符合实际情况的结合面法向接触阻尼能量耗散及其损耗因子模型。通过仿真发现,结合面法向接触阻尼能量耗散及其损耗因子随着分形粗糙度参数的增大而增大,随着分形维数的增大先减小后增大,且在1.2附近出现最小值;结合面法向接触阻尼能量耗散随着法向接触载荷的增大而增大,损耗因子随着法向接触载荷的增大而减小;考虑弹塑性过渡机制情况下法向阻尼能耗低于仅考虑弹性和塑性机制情况下的法向阻尼能耗。

When modeling the normal contact damping energy dissipation in the joint surface,it is incomplete to consider only the energy storage during elastic deformation and the energy dissipation during plastic deformation of the asperity,because there is an elastic-plastic deformation case of the asperity.By introducing the asperity loading and unloading model,the energy storage and dissipation of the asperity in elasto-plastic deformation are separated,and a more realistic model of the normal contact damping energy dissipation and its loss factor is established.The model simulation results show that the normal contact damping energy dissipation and its loss factor increase with the increase of fractal roughness parameter.With the increase of fractal dimension,the energy dissipation and loss factor of the normal contact damping first decrease and then increase,and the minimum value appears near 1.2.The energy dissipation of the normal contact damping of the joint surface increases with the increase of the normal contact load.The loss factor decreases with the increase of the normal contact load.The normal damping energy consumption considering the elastic-plastic deformation mechanism is lower than the normal damping energy consumption considering only the elastic and plastic deformation mechanisms.