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为实现岩石破裂过程的超声波探伤成像–声发射一体化监测,深入研究岩石损伤演化与声发射间的关系。在超声波透射型探测和射线追踪成像理论基础上,从岩石内部区域相关的角度考虑岩石的不均匀性、各向异性,构建了基于声发射AST模式的岩石损伤探测成像方法。着重阐述了损伤探测成像方法的原理、离散速度场的构建、分量速度场矩阵的求解、多分量速度场间复合运算规则、待估物元的搜索方法及最终的损伤探测成像方法。通过选择较为完整无明显缺陷的岩石试件、含有严重损伤缺陷的岩石试件以及存在特殊结构的岩石试件,进行成像方法验证。研究结果表明:基于声发射AST模式的岩石损伤探测法具有良好的探测与成像效果,不仅能定位岩石内部损伤缺陷,还能识别与损伤缺陷相关的弱化区域。该方法可以实现超声波探伤成像与声发射信号的同步监测,为后期开展岩石损伤区域圈定、损伤动态发展的跟踪、岩石破裂动态损伤多指标量化评价、岩石破裂损伤演化与声发射间的关系研究提供了基础。
In order to realize the integrated ultrasonic flaw detection and acoustic emission monitoring of rock rupture, the relationship between rock damage evolution and acoustic emission is deeply studied. Based on the theory of ultrasonic transmission detection and ray tracing imaging, the rock inhomogeneity and anisotropy are considered from the perspective of the correlation of rock internal regions, and a rock damage detection imaging method based on acoustic emission (AST) mode is constructed. The principle of damage detection imaging method, the construction of discrete velocity field, the solution of component velocity field matrix, the compound operation rule of multi-component velocity field, the search method of matter-to-be-estimated element and the final damage detection imaging method are emphatically described. The imaging method was validated by selecting rock specimens with relatively complete defects without obvious defects, rock specimens with severe damage defects and rock specimens with special structures. The results show that the rock damage detection method based on acoustic emission (AST) model has good detection and imaging effects. It can not only locate the internal damage defects in rocks, but also identify the weak areas related to the damage defects. The method can realize the synchronous monitoring of ultrasonic flaw detection imaging and acoustic emission signals, and provide a method for late detection of delineation of rock damage area, tracking of damage development, multiple quantitative evaluation of dynamic damage of rock fracture, relationship between rock damage evolution and acoustic emission The foundation.