Application Research Of Acoustic Emission Signal Processing And Positioning Method Based On Ground Pressure Monitoring

As the key content of ground pressure monitoring,acoustic source location has a vital position and practical significance.Based on the multi-channel ground pressure monitoring system of Yuxi Dahongshan Mining Co.,Ltd.,this paper conducts acoustic source localization research based on theoretical research and field investigation.In the research process,this paper obtains the technical means of processing acoustic emission signals through theoretical analysis,theoretical calculation,field test,programming calculation and other research methods,and realizes the localization algorithm by using mathematical software.Based on the full text,the main research work and research results of this paper are as follows:1?At the beginning of the thesis writing,I have consulted a large number of relevant literatures in this field at home and abroad,and conducted a comprehensive and systematic understanding and learning of ground pressure monitoring and early warning technology,acoustic emission signal analysis and processing methods,and acoustic emission source localization technology,and the main research content and research methods of this paper are clarified.2 ? Through on-the-spot investigation,we learned to master the ground pressure status of Dahongshan Iron Mine and the hardware components and software functions of the ground pressure monitoring system,and the system is used to obtain the position coordinates of the acoustic emission sensor near the 370 segment of the Dahongshan Iron Mine,the position information of the acoustic emission source and the waveform data of the acoustic emission signal corresponding thereto.The signal propagation speed of the Dahongshan Iron Mine under ground pressure was tested by the real-time data acquisition and waveform processing module of the system,and the measured P wave velocity is6000m/s.3?The time domain and frequency domain analysis of the acoustic emission signals are carried out respectively,and the types of different acoustic emission signal sources commonly found in underground wells are identified by using the time domain characteristics of the acoustic emission signals.On the basis of frequency domain analysis,the algorithm of MATLAB software is used to realize the spectrum analysis,Fouriertransform and wavelet analysis of acoustic emission signals,and further analyze the frequency domain characteristics of different acoustic emission signals,which facilitates the subsequent research work.4 ? Relying on the principle of wavelet transform denoising,the maximum and minimum criterion thresholds(minimaxi rule)and the soft threshold function are selected for reconstruction denoising.After analyzing the wavelet denoising effect and comparing the root mean square error(RMSE)of the denoised signal,it is concluded:The denoising effect of the acoustic emission signal of Dahongshan Iron Mine using Db6 wavelet for two-layer decomposition is the best.On this basis,the long-short-time average(STA/LTA)algorithm is used to discriminate and read the arrival time of the acoustic emission signal generated underground.After repeated argumentation research on the spot,it is concluded:When the ratio of STA/LTA reaches 3.00,the point is considered to be the starting point of calculation of the arrival time of the P wave.5?Taking the time difference positioning principle as the guidance of the acoustic emission source localization method,the time difference linear positioning algorithm and the Geiger iterative localization algorithm are mainly studied.Through the MATLAB programming calculation,the application of the positioning method in the Dahongshan iron Mine is realized.After comparing the error of the positioning results of the two methods,it is concluded that:The Geiger iterative positioning algorithm is more suitable for the positioning research under the actual working conditions.