关键词: 单轴压缩, 声发射特征, 弱胶结, 破坏形式

Abstract: In order to research the acoustic emission characteristics and failure patterns of the weak sandstones，uniaxial compression tests together with the acoustic emission monitoring tests on specimen from Xiaojihan Coal Mine are conducted.The test indicated that the characteristic curves of the acoustic emission of six specimens were summarized as the splitting type and the fracturing type.For splitting type curves，the acoustic emission events occurred rarely in the linear elastic and stable development of micro-cracks stage，while they occurred rapidly from the later yielding stage to earlier destruction stage，and still existing after the destruction stage.For fracturing type curves，in linear elastic and stable development of micro-cracks stage more acoustic emission events occurred than those of the splitting type curve，and in yielding stage acoustic emission events increased stepwise until the peak strength，moreover acoustic emission quiet period existed before the peak strength.Furthermore，the failure forms can be divided into single shearing failure and X-type conjugate failure.For single shearing failure，the specimens show higher strength relatively，and its form of failure generally corresponded to acoustic emission characteristic curve of splitting type.Meanwhile，for X-type conjugate failure，the specimens show lower strength，and its form of failure generally corresponded to acoustic emission characteristic curve of fracturing type.The results are of great significance for prediction of the roof deformation failure under high intensity mining.

Key words: Uniaxial compression, Acoustic Emission characteristics, Weak cementation, Failure mode