Research on plane strain model test of rockburst of underground cavern in hard brittle rockmass

摘要

In order to study the failure process and mechanism of rockburst of underground cavern, the physical model materials of hard brittle rock which is gotten though similar material test and have the tendency of rockburst are prepared for making cavern physical models of 1000mm*1000 mm*1000mm and Φ 150mm. Then plane strain physical model test is carried out on the machine for large-scale physical model test in geotechnical engineering. The results show that the state of rock switches from the elastic to the plastic on the condition that horizontal and vertical load of the model is equal and increase synchronously. The failures of hard brittle rock burst in surrounding rock are mainly in the initial crack of rock. The phenomenon of separation by layer appears around the cave walls. Damage occurs in very short time and extremely narrow loading range and is sudden with chippings popping or fragments falling. After failure rock stress readjusts and keeps relatively stable in a relatively long time and loading range.