关键词: 岩土工程, 岩土力学, 裂隙岩体, 数值模拟, 破坏

Abstract: The structural plane characteristics of rock mass have important influence on the deformation and failure of rock mass. It is of great significance to study the characteristics of crack expansion, strength and energy during the failure of cracked rock mass. Selecting the physical and mechanical parameters of limestone and adopting the state of one-way compression stress, the influence of different horizontal position, dip angle and length of the initial fracture on the cracked rock mass was analyzed by numerical simulation software RFPA in 14 working conditions. The simulation results show that the horizontal position of the crack has little effect on the upper and lower propagation angles of the crack; with the increase of crack horizontal position a, the time of upper crack growth line appears earlier and earlier, and the influence of crack horizontal position on its peak strength is less; with the increase of crack dip angle, the upper and lower propagation angles decrease rapidly, and the peak strength of specimen increases; with the increase of crack fracture length, the upper and lower propagation angles increase rapidly, and the peak strength tends to decrease. The above three factors have little influence on the residual strength of cracked rock mass. Through the energy and acoustic emission activities of 14 working conditions, it is found that: when the prefabricated fracture is far away from the axis, it is of “double-peak” type; when the fracture is steep, it is of “thin-high” type; when the fracture is gentle to medium dip, it is of “short-fat” type. The research results are of great significance to the prevention and control of dangerous rock in limestone area.

Key words: geotechnical engineering, geotechnical mechanics, cracked rock mass, numerical simulation, failure