Experiments and numerical simulations on dynamic crack behavior at the interface of layered brittle material

Abstract

Crack behavior at the interface between two materials is the core problem of layered material fracturing. In this paper, first, experimental tests were conducted on layered material using a drop weight test system following the caustics method. The layered material was made of poly (methyl methacrylate) (PMMA) and epoxy resin bonded with Loctite-330 at two inclination angles (30 and 60 ). A corresponding numerical simulation was carried out using continuum-discontinuum element methods. Crack propagation is found to mainly occur in mode I in the PMMA and epoxy resin but follows a mixed cracking mode at the interface. The fracture parameters of the crack tip in the layered materials changed substantially owing to the existence and change of the interface structure. After the crack enters the interface, the crack propagation speed increases significantly. Higher crack dip angles are associated with greater crack propagation speed increases after entering the interface. The simulation results indicate that the interface strength properties affect crack behavior at the interface. This effect also varies as a function of interface inclination and impact velocity.

A new cube movement test for verification of simulations of contact processes of blocks of different size in geological hazards

“…It is a hybrid method that can simulate the whole process from a continuous to a discontinuous geological body. 13,14 The CDEM was successfully applied to the analysis of a variety of geotechnical engineering problems, such as coal caving mining, 15 propagation of hydrofracturing cracks, 16,17 rock blasting, 18,19 crack propagation of brittle materials, 20,21 deformation of tunnels, 22 and landslides. 23,24 The success of modern simulation models for granular matter requires realistic and efficient consideration of frequently complex particle shapes of geological materials, see Zhao et al 25 for a comprehensive appraisal of state-of-the-art computational models for granular particles of either naturally occurring shapes or engineered geometries.…”