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为了探究砂岩声发射活动及其破坏特征之间的关系,研究声发射活动和砂岩破裂特征的变化规律,进行了砂岩声发射力学特性试验。研究结果表明:不同加载阶段砂岩声发射活动强弱不同,与其内部的裂隙发育演化过程有密切关系。当应力高于起裂应力时,声发射事件逐步上升,砂岩体积逐渐增加;当应力高于扩容应力时,声发射事件急剧上升,占全过程的53.9%,体积应变值在该阶段达到最大。在砂岩破坏过程中,声发射活动越剧烈,体积应变绝对值越大,体积应变和声发射活动都随着砂岩内部裂隙发展,当砂岩开始产生微裂隙时,声发射能量相对于声发射事件率在接收信号方面有一定滞后性。
In order to explore the relationship between the acoustic emission activity of sandstone and its failure characteristics, the variation rules of acoustic emission activities and sandstone fracture characteristics were studied, and the acoustic emission mechanical properties of sandstone were tested. The results show that different loading stages of sandstone have different acoustic emission activities and are closely related to the internal evolution of fractures. When the stress is higher than the initiation stress, the acoustic emission gradually increases and the volume of sandstone gradually increases. When the stress is higher than the expansion stress, the AE event rises sharply, accounting for 53.9% of the whole process, and the volume strain value reaches the maximum at this stage. During sandstone destruction, the more intense acoustic emission, the greater the absolute value of volumetric strain, and the volumetric strain and acoustic emission activities develop along with the internal cracks in sandstone. When the sandstone starts to produce micro-cracks, the acoustic emission energy relative to the acoustic emission event rate There is a certain lag in receiving the signal.