关键词: 声发射, 加载模式, 岩石破坏

Abstract: To investigate the evolution of acoustic emission (AE) parameters and the differences in the fracturing and failure processes of main roof rocks in coal seams under various loading modes，uniaxial com⁃ pression，direct tensile，and indirect tensile tests were conducted on main roof rock samples from the 15# coal seam of the Xinshanghai No.1 Mine，with AE signal characteristics recorded throughout. The results show that the uniaxial compressive strength of the main roof rock is 79.15 MPa，the direct tensile strength is 5.2 MPa，and the indirect tensile strength is 1.3 MPa. In the uniaxial compression test，the AE damage ac⁃ celeration point appears at a stress level of 20%. In the direct tensile test，it occurs at 70% stress level，and in the indirect tensile test，it emerges at 90% stress level. Under different loading modes，micro-crack de⁃ velopment dominates throughout the entire uniaxial compressive failure process，whereas the scale of crack development in tensile tests is larger than that observed in compression tests. In compression tests，rock fail⁃ ure progresses from small cracks to larger fractures under applied stress，with the development of major frac⁃ tures leading to instability and failure. The indirect tensile test is similar to that.

Key words: acoustic emission, loading modes, rock failure