Statistical analysis of tangential contact stiffness of joint surfaces

To investigate the tangential contact stiffness of joint surfaces, the asperity contact of the joint surfaces is considered as an elliptically shaped contact, with the major and minor semi-axes of the contact areas assumed to follow a two-dimensional Gamma distribution. Hertz theory for the pressure distribution on an elliptical contact area is applied to solve for the tangential contact stiffness in a single asperity. Numerical results reveal a change in the tangential contact stiffness, with the influential factors being normal load, tangential load, eccentricity of elliptical asperities, correlation coefficient of asperity distribution, measured asperity height, and standard deviation of asperity distribution on joint surfaces. All of the results should provide theoretical guidance for evaluating or refining the tangential contact stiffness of joint surfaces.