Numerical Study on Wave Effect of the Frictional Interface

Interface friction is a common natural phenomenon. Based on the micro-contact fracture mechanism of friction, a two-dimensional interface friction model including a triangular micro bulge is established with linear elastic constitutive relationship and D-P failure criterion. The early dynamic behavior of the interface under transient loading is numerically calculated and analyzed by the finite element simulation method. The research shows that in the micro process of loading, there exist significant stress fluctuations and fine structure characteristics at frictional interfaces. The evolution of the wavefront in the near region of the interface has symmetrical diffusion. The interaction of the incoming stress disturbance and the micro bulge will induce the fracture of the bulge, resulting in a three-wave profile centered on the fracture surface: longitudinal wave, transverse wave, and interface wave. A new interesting phenomenon is that at the moment of loading, a micro stress disturbance is generated synchronously from the interface and propagates to the substrate in the form of longitudinal waves. More comparative examples and analysis show that the mechanism of this disturbance is related to the overall gravity micro-adjustment acting on the interface. This work reveals the early wave effect of interface friction and its micro fracture mechanism, which is expected to provide an effective way for earthquake prediction and to advance the earthquake prediction time.