矸石充填体受压裂纹扩展规律及声发射特性研究

为研究矿井矸石充填体内外破坏形式以及裂纹演化规律，利用PCI-2型声发射测试仪和压力试验机等仪器，分析不同水灰比、胶凝材料条件下，矸石充填体的强度、AE信号以及裂纹演化规律。结果表明：矸石充填体3d强度最小为3.6MPa，满足充填要求，水灰比的增加使得矸石试件的应变曲线斜率减小，提升了试件的抗变形能力|应力最大时，AE活动最为剧烈，试件裂纹上下贯通，呈张拉破坏|矸石充填体裂纹演化分为：闭合压密阶段、线弹性变形阶段、不稳定延伸阶段、峰后变形阶段。闭合压密阶段与线弹性变形阶段内，试件AE信号较弱|不稳定阶段矸石试件AE活动剧烈，内部颗粒碰撞明显|峰后变形量大，AE活动骤减。

Crack propagation and acoustic emission characteristics of gangue fill mass

In order to study the internal and external failure modes and crack evolution law of mine fill mass,PCI-2 acoustic emission tester and pressure testing machine are used to analyze the strength,AE activity and crack evolution of gangue fill mass under different water cement ratio and cementitious materials.The results show that:The minimum 3-day strength of gangue filling mass is 3.6 MPa,which meets the filling requirements.The increase of water cement ratio reduces the slope of strain curve of gangue specimen and improves the deformation resistance of specimen.AE activity is the intensest under the maximum stress,and the upper and lower cracks of the specimen are connected,showing tensile failure.The crack evolution of gangue fill mass is divided into closed compaction stage,linear elastic deformation stage,unstable extension stage and post-peak deformation stage.During the closed compaction stage and linear elastic deformation stage,the AE signal of the specimen is weak;the AE signal of gangue specimen in unstable stage is intense and the internal particle collision is obvious.The post-peak deformation is large,and the AE activity decreases sharply.