Research on dynamic compressive behaviors of marble under high strain rates with split Hopkinson pressure bar

摘要

The strain rates can significantly change the mechanical properties of rock materials. In this study, the static and dynamic compressive behaviors of marble under different strain rates were investigated by a series of compressive tests. The highest strain rate reached to1230s(-1) by using a split Hopkinson pressure bar (SHPB). A high-speed camera was employed to capture the fracture and failure progress of rock specimens during SHPB tests. The compressive stress-strain response of the tested rock material and the strain rate effects were analyzed. The experimental results showed that the fracture behavior and mechanical properties of marble have a significant correlation with the strain rate. Under quasi-static loading, the failure process of marble was dominated by one main crack. However, under dynamic loadings, there were more micro-cracks were generated within the specimens with the increase of strain rate. Moreover, the predominant failure modes of rock specimens change from intergranular fracture to transgranular fracture. The ultimate compressive strength increased with the increase of strain rate, and the grain size of the rock fragment decreased with the increasing strain rate.