A 3-D perspective of dynamic behaviour of heterogeneous solids

Abstract

Abstract. The dynamic behaviour of concrete-like materials under high strain rates has been a subject of continuous scrutiny over the years. A prevailing explanation attributes much of the dynamic increase of strength, especially under compression, to the macroscopic inertia confinement. Studies conducted by the authors' group using meso-scale computational models suggest that the heterogeneity of the material composition, in particular the involvement of the aggregates, also plays a sensible part in the process of damage evolution and the increase of the bulk strength under high strain rates, and a detailed investigation into this effect would benefit if a realistic representation of the heterogeneity in 3D can be achieved. This paper presents some recent progress in the development of a 3-D meso-scale computational model incorporating randomly-shaped 3-D aggregate particles, including the general validation of the model, and application in the simulation of the dynamic response of concrete under high strain rate compression.

A mesoscale interface approach to modelling fractures in concrete for material investigation

“…However, the true mechanism underlying the occurrence of the DIF is still a subject of continued debate. Various analytical and numerical studies in more recent years, including an analysis using a 3D mesoscale model [41], A similar displacement controlled loading via a velocity boundary condition as in the quasi-static analysis is used in the dynamic simulation, but a higher velocity and a shorter time duration is adopted in order to achieve a desirable strain rate.…”