ABSTRACT
ABSTRACT: In order to obtain more accurate normal contact stiffness of joint interfaces theoretically, a contact stiffness model was developed and studied. The proposed model uses the fractal theory for characterizing surface topography and the contact mechanics theory for modeling contact stiffness of microcontacts, while the influence of the elastic, elastoplastic and fully plastic deformation regimes of contacting asperities are considered. Solutions for the force-displacement relationship in the elastoplastic regime are done by the well-supported assumptions: the microcontact area and microcontact normal load are enforcing continuity between the elastic and fully plastic regimes. Numerical calculation and simulation results reveal the effect of fractal parameters including fractal dimension and fractal roughness, and normal contact load on the normal stiffness. It is shown that normal contact stiffness increases with the increment of normal load and fractal dimension, and decreases with the increment of roughness parameter.
