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中文摘要：
应用声发射及其定位技术，在单轴压缩载荷作用下，应用盖格尔定位算法，采用试验方法研究包括含不同预制裂纹的花岗岩岩样破裂失稳过程中其内部微裂纹孕育、萌生、扩展、成核和贯通的三维空间演化模式。试验结果表明，声发射定位能够反映岩石裂纹动态演化过程，声发射事件的产生主要是由于裂纹扩展产生的，并随应力-应变变化表现出不同的特征：在初始加载阶段至初始裂纹出现之前，其声发射活动不很明显；一旦岩样出现初始裂纹，在相应应力点声发射事件明显增多；裂纹稳定扩展至岩石完全破坏之前，声发射总数应变曲线与应力-应变曲线平行；在微裂纹扩展的非稳定阶段至岩石破坏瞬间，声发射活动变得异常活跃，声发射事件变化率最大。在完整岩样声发射事件定位结果中，出现声发射定位事件的空白区，宏观裂纹的贯通恰在声发射事件的空白区之内，借此可以实现对岩石裂纹贯通位置预测；声发射定位结果也是岩样内部应力场演化过程的宏观表现，可直观地反映岩样内部裂纹扩展空间位置、扩展方向以及裂纹扩展的空间曲面形态，这对于深入研究岩石破裂失稳机制是十分有意义的。
英文摘要：
Acoustic emission（AE）, which is produced by the micro-cracks occurrence or growth, is a ubiquitous phenomenon associated with brittle fracture in many materials. AE technique can be used to monitor the micro-cracks development in the rock sample continuously and in-real-time, which is better than other methods. AE location technique is employed to study rock failure process. It is investigated using granite samples with different precut cracks; and AE sensors are mounted on the surface of the sample. A Geiger location algorithm allows AE event location from first arrival times to be determined by AE sensors, which is applied to study the crack initiation and propagation process, also to analyze the crack spatial evolution mode with stress changing during the total loading process. The experimental results show that AE activity represents different characters with stress-strain changing during the total loading process; the quantity of the AE events is very little from the initial loading to crack initiation; when the initial crack generates, AE events apparently increase; AE events are in quiet period after crack initiation up to the time before crack propagation; AE activity sharply increases from crack stable propagation up to crack unstable propagation, especially in crack unstable propagation step, AE events reach to the most quantity in the division strain. There is ＂void space＂ of AE events during the AE location results; the ＂void space＂ of AE events is the position of macroscopic crack breakthrough, which can be used to predict the crack breakthrough position of rock samples. Meanwhile, AE location results are also direct reflection of interior stress field propagation process. AE location results also reflect directly the spatial position, direction and spatial curved face of crack propagation in the rock sample, which is very significant to study the mechanism of rock failure.
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