EFFECTS OF STRENGTH WEAKENING AND INTERFACE SLIPPING ON ROCK MASS WITH DIFFERENT DIP ANGLE STRUCTURE PLANES

摘要

Micro-mechanical behaviors of rock masses with structure planes can provide information regarding precursory characteristics of macro-fracture of strata and rock bursts. Hence, numerical simulation with uniaxial compression test is conducted using Realistic Failure Process Analysis (RFPA). Then, mechanical properties and progressive failure processes for rock masses with different dip angle structure planes are studied, and the macroscopic fractures, mechanical responses, and acoustic emission (AE) responses of rock masses are analyzed. Moreover, the strength weakening and interface slipping effects with different dip angle structure planes are revealed. The results show that rocks with different dip angle structure planes show significant strength and interface slipping effects. A small dip angle structure plane has little influence on the rock strength and interface slipping, which mainly manifests as failure in rock interiors. For medium dip angle structure plane, the rock strength decreases obviously, and interface slipping is notable along the structure plane. The effects caused by the weak plane are more prominent with rising dip angles. Compared to rocks with small dip angle structure planes, those with medium dip angle structure planes are more easily broken. However, the total energy released and total AE counts are smaller, indicating less serious bursting liability from rock failure.