Experimental Study On Influential Factors Of Acoustic Emission Location Experiment

For brittle rock, the rock failure process is sonsistent with its internal microcracks evolution. The generation and expansion of microcrack accompanied by rapid release of the elastic wave and propagates within the rock. And that is acoustic emission. Acoustic emission signals are generally weak, so they need the help of specialized equipment to be monitored and using multiple acoustic emission transducers can locate the position of the acoustic emission. But due to the physical characteristics of the complexity and non-stationary characteristics of acoustic emission signals, as well as the influence of shape, size, porosity and rock samples, etc. accuracy of acoustic emission location is poor. Thus the research and application of acoustic emission technology has been very limited. With the help of the important factors of physical experiments used to study the location accuracy of acoustic emission, it has important theoretical and practical value on more precise information on the inversion of acoustic emission sources.In this paper, the author combine the laboratory experiments with theoretical analysis. Through the broken lead experiments under different conditions to study location accuracy of acoustic emission, and then analyze the resulting errors. Using the a large number of acoustic emission data and based on the various factors,analysis and deal with the influence the positioning accuracy of acoustic emission theoretical to get more accurate AE source location information.①Use the PCI-2 type of acoustic emission testing system to carry out the sound of sandstone under different conditions of specimen size lead-off location emission test and discuss on the influence on the location accuracy of specimens in different sizes, analysis linear law between size and positioning errors.②Carry out lead-off location emission tests under different distances between sound transducers and boundary on the sandstone rock specimens. Discuss on the boundary effect on the location accuracy and combine with the research about the sizes of specimens to study about the best lead-off distance on different sizes.③Carry out lead-off location emission tests under different couplant on the sandstone rock specimens. Analysis comparatively about the effects when choose different couplans t on the location accuracy specimens and find out the most suitable coulant to imprive the accurancy.④Carry out lead-off location emission tests under different plate thickness conditions and investigate the influence of different plate thickness and coupling agents on the sandstone rock specimens. Analysis reasonable thickness of transducer between acoustic emission transducer and specimen sandstone rock specimens and provide theoretical guidance on t design of plate thickness on true triaxial testing machine.