Acoustic Emission Characteristics During The Evolution Of Damage Of Water-bearing Rocks Based On Wavelet Transform

The AE activity can reflect the conditions of the inner injury evolution of materials. The AE technique is applied to actual time monitoring of the process of the injury for the rock material and the research of the inner injury in the loading conditions. This is a very key for the research of the material destruction. It is difficult for the AE technique to be applied in the material injury monitoring which the equitable and overall analysis of the AE data and to estimate the injury to the rock with this method. The present situation, a lot of domestic and foreign scholars on the AE technique is applied to the rock injury monitoring conducted extensive research, encourage the development and application of this domain. It is just a single theory for different types of rock injury and they does not take into account the influence of water on the AE signal which is an unknown spot of the rock acoustic emission research on the properties. What is more, rock in the nature contains some water, the groundwater is an important factor affecting the stability of engineering rock rheology, because of water in the rock, the AE signal becomes more complicated. For resolving this problem, on the foundation of AE experiment of rock injury process. based on the wavelet transform, with different water content sample injury process of AE characteristics was studied.Selecting sandstone and diorite with different water content to make the samples.The samples with different water content are analyzed by uniaxial compression experiment, in the meantime using the AE experiment instrument for monitoring acoustic emission of the process of the experiment data and records them.Using wavelet transform method, denoising by soft threshold and hard threshold method and through the comparison and research,it is known that the RSN and RMSE for soft threshold method is better,so soft threshold denoising method makes the signal-noise separation more effectively; secondly making the frequency band energy by wavelet decomposition as characteristic parameters to search the rock AE signal energy distribution.It has important realistic meaning of the development tendency and the pattern of injury forecasting the deformation process of the rock. Providing a theoretical basis for the injury of the rock. It might has suggest lessons for the future for this research for forecasting some mine disaster with the technology of micro-seismic monitoring.