Research on the development and application of acoustic emission technology for solid materials

Research on the development and application of acoustic emission technology for solid materials

The location of the acoustic source can help to strengthen these rock projects in a targeted manner, prevent disasters, and reduce accident losses. Based on the research on rock acoustic emission characteristics, this project has developed a rock acoustic emission monitoring and positioning instrument system. A triaxial acoustic emission probe is used to receive the full waveform of the acoustic emission signal, detect the occurrence of the acoustic emission event, and use the PS wave arrival time difference method to locate the acoustic emission source. The instrument system can be applied to rock projects such as mine slopes, mountain slopes, railway and highway slopes, and reservoir dams, and can provide an effective technical means for stability monitoring and safety evaluation of these rock projects. The research results of the project meet the requirements of the research objectives in terms of technology and performance.
(1) Through the study of indoor and outdoor rock acoustic emission characteristics, the frequency, intensity, attenuation and other characteristics of the acoustic emission signal of general rock projects are clarified.
(2) The developed instrument system can receive the acoustic emission signal components in three axes, with a sensitivity of 2500PC/g and an operating frequency of 1-2kHz.
(3) The acoustic emission signal acquisition is distributed, three-way parallel, and the speed is 50KSPS.
(4) The instrument system can monitor 8 stations at the same time and collect 24 channels of data. Based on the control of 100 meters for each station, the maximum monitoring line can reach 800 meters.
(5) The location of the acoustic emission source is determined by the PS wave arrival time difference method of a single probe (single station).
(6) A variety of technical means are used in hardware and software to improve the instrument's ability to resist environmental noise.
(7) Digital signal transmission technology is used, with a signal fidelity transmission distance of more than 1.2km, and a transmission speed of up to 9600bit/s depending on the monitoring distance. The project research results have achieved success in key technologies such as triaxial reception of acoustic emission signals, single probe PS wave positioning, and noise resistance. The instrument system fills the domestic gap and reaches the level of international advanced instruments.