Research on the Failure of Brittle Rock-like Samples Based on Its Acoustic Emission Characteristics under the Condition of Uniaxial Compression

摘要

There is less research on the accordance relationship between AE characteristics and failure process including the starting time and duration of failure of brittle rock. The different brittleness rock-like samples made of rosin and grout mortar have been researched by the uniaxial compression test and the acoustic emission (AE) experiments. Compared with the samples without rosin, brittleness index of the rock-like samples with rosin increase by 30%-40%, starting time of failure is 41%-57% later and failure duration is 38%-48% shorter than those with lower brittleness. Combined with the initial failure time of rock-like samples and its ringdown count rate, failure characteristics among those rock-like samples with different brittleness are analyzed. Seen from the AE ringdown-time curves, there exists a stable period until the AE ringdown rate reaching to peak point, the length of its duration is directly proportional to the brittleness of rock-like samples, and the longer the duration is, the more energy can be accumulated, meanwhile the failure velocity is faster than those rock-like samples with lower brittleness. All these results can offer some references to research the starting time of failure and AE features of brittle rock and effectively promote the prediction of failure of brittleness rock.