A contact force model in the dynamic analysis of contactable cracks

In this paper a finite element method in the time domain is proposed to analyze the dynamic response of contactable cracks. By this method, the contact normal stress caused by impact or contact of the crack faces can be directly obtained and then the motion of the model containing the contactable cracks can be calculated, and the processes of contact, slip and separation of the crack faces can also be correctly determined and simulated. The method proposed can be used to study the scattering problems of an elastic wave caused by the crack and the dynamic extension problems of the crack arising from impact or cyclic loading. Numerical examples indicate that the method is efficient and accurate enough. It is also shown that the effect of dynamic contact of crack faces on the motion of itself and the area near the crack is significant by comparing the results with the contact considered and neglected.