Study on Crack Propagation of Rock Bridge in Rock-like Material with Fractures under Compression Loading with Sudden Change Rate

In order to study the influence of sudden change loading rate on crack propagation and failure mode rock bridge fractured mass, specimens used in this paper were rock-like materials containing two prefabricated fractures. The mechanical properties under different constant rates changes tested. photographic monitoring acoustic emission carried out at same time. results show that: (1) process loading, specimen shows characteristics approximate elastic deformation, stress-strain curve after is similar corresponding rate. (2) Combined with detection, it found that when not much before mutation, mutation similar. low-speed stage, count generally low, while high-speed high. from easily induces stress drop, resulting generation increase count. (3) during development period plays a decisive role specimen. Before rate, within certain range has little effect When low early stage high, which will cause some damage inside As result, even if final peak may be different.