Present situation and prospect of coal mine safety monitoring based on fiber bragg grating and distributed optical fiber sensing technology

At present, domestic coal mines generally adopt the mining status of high intensity (large mining height). With the rapid development of intelligent coal mining, higher requirements are put forward for coal mine safety monitoring. The existing coal mine roadway is generally thousands of meters long, and the working face area can reach several square kilometers. It is difficult to obtain such a large area of monitoring information accurately and in real time by manual means or using traditional point state sensors. Because the optical fiber material has the advantages of easy processing, high wear resistance, strong corrosion resistance, good insulation and strong resistance to groundwater and electromagnetic interference, with the development of modern optical basic theory and optical fiber communication, the manufacturing cost of various optical devices is also decreasing. It is an inevitable result of the development of optical fiber monitoring technology in the field of monitoring. The main component of optical fiber is silica, which is an intrinsically safe sensor, especially suitable for monitoring in high-risk environments such as coal mines. This paper systematically summarizes the basic principles, advantages, disadvantages and applicable conditions of various optical fiber sensing technologies, and focuses on the application status of optical fiber grating and distributed optical fiber sensing technology in coal mine safety monitoring, such as coal mine shaft wall deformation, goaf stratum subsidence deformation, mining overburden deformation, roadway safety and stability, coal mine gas monitoring and early warning, etc, The application prospect of distributed optical fiber monitoring technology is prospected. Through the analysis of the existing literature, the following conclusions are obtained:Optical fiber sensing technology can meet the basic requirements of coal mine safety monitoring under different conditions and can be used in various harsh environments. Compared with existing conventional testing methods and technologies such as traditional manual monitoring and point-state sensor, optical fiber monitoring technology has high sensitivity, large monitoring range, and can carry out continuous and large-scale distributed monitoring in time and space. It has great advantages in coal mine safety monitoring and has a good application prospect.