An adaptive contact model involving friction based on peridynamics

Abstract

In peridynamics (PD), various existing contact models are difficult to resolve the contradiction between identifying contact surfaces and calculating contact forces accurately. This contradiction poses a challenge to the quantitative analysis of impact, extrusion, friction, and closure cracks. A friction contact model in PD based on family material particles was proposed to realize the adaptive identification of contact surfaces. The boundary normal vector was derived from the directional characteristics of the boundary reaction force. According to the dynamic equations of the boundary material particles, the proposed contact model achieves the precise calculation of the contact forces. In addition, an improved bond-based peridynamic model with shear bonds (improved PDS model) was extended to a three-dimensional form to achieve accurate deformation analysis of spatially complex deformable bodies. By combining the improved PDS model with the proposed contact model, the non-objectivity of the relative velocity is eliminated and the computational accuracy of the contact model is greatly improved. Quantitative analysis of the spatially deformed cantilever beam proves that the 3D improved PDS model possesses high accuracy of displacement calculation. Several examples with non-negligible friction were conducted to verify the reliability and efficiency of the proposed contact model. The results show that the proposed contact model can significantly improve the accuracy of displacement analysis and damage prediction in contact problems with non-negligible friction effects.