A Mine Seismic Monitoring Method Based on Fiber Bragg Grating

Abstract

The invention discloses a mine earthquake monitoring method based on fiber gratings. At least thirty coal sample test blocks are randomly selected from underground to-be-monitored area coal bodies, and change conditions of resonance wavelengths of the fiber gratings are obtained; multiple monitoring points are selected around the to-be-monitored area coal bodies to enable the monitoring points to surround a to-be-monitored area, multiple fiber grating sensors transmit real-time fiber grating resonance wavelength signals to an underground monitoring sub station through multi-core communication cables; the underground monitoring sub station transfers optical signals to a ground receiver; the change conditions of the resonance wavelengths of the fiber gratings of each monitoring point are obtained from the processed signals through a data processing computer; and a real-time comparison between change of the resonance wavelengths of the fiber gratings, monitored in real time and change rules of the resonance wavelengths of the fiber gratings, obtained through tests until comparison consistency occurs, and it is indicated that the coal bodies have the risk of mine earthquakes. The method provided by the invention is high in accuracy and good in real-time performance.

Description

technical field [0001] The invention relates to a method for monitoring earthquakes in mines, in particular to a method for monitoring earthquakes in mines based on optical fiber gratings. It belongs to the technical field of shoes. Background technique [0002] In recent years, in the process of coal mine production, with the increase of mining depth and intensity, mine seismic activities have become increasingly frequent, and the release of energy has made mine pressure more and more serious, and even rock bursts have occurred, causing serious disasters; however, based on "movement and static Rockburst disasters also occurred during the mining of shallow coal seams in western my country, causing heavy losses. The pressure in the coal rock mass exceeds the strength limit, and the energy accumulated in the coal rock mass around the roadway or the stope is released suddenly, and an explosive accident occurs in the roadway, and the power throws the coal rock to the roadway and...

AI Technical Summary

Problems solved by technology

The mechanism and process of rock burst are relatively complicated. At present, these technologies still have many deficiencies, such as low sensitivity and high cost of online stress monitoring and real-time monitoring systems; elastic wave CT inversion technology cannot achieve real-time early warning; microseismic methods and Acoustic emission technology and electromagnetic radiation technology have large errors and low accuracy

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