[Chinese instrument network instrument research and development] Impact rock pressure, also known as rock burst, refers to the dynamic phenomenon that the rock mass around the roadway or working face can be instantaneously released due to elastic deformation, resulting in sudden violent destruction, often accompanied by the throwing of coal rock masses. The phenomena of loud noise and air waves are sudden, complex, and extremely destructive. They have always been an important disaster in the field of deep resource exploitation in our country.
How to strengthen early warning and monitoring of rockburst has always been an important issue. Under the new situation of the development of science and technology and the development of the Internet of Things Big Data, the Construction Process Mechanics Group of the Institute of Rock and Soil Mechanics, Chinese Academy of Sciences conducted in-depth studies on three-dimensional stress sensor technology theory, real-time sensing of state information, and intelligent online processing. A dynamic monitoring and early warning system for rockburst in coal mines was developed and great progress was made in the early warning of ground pressure.
First of all, the Institute of Rock and Soil Mechanics, Chinese Academy of Sciences independently researches and develops a high-precision fiber grating three-dimensional stress sensor. Its corrosion resistance, resistance to groundwater and electromagnetic interference, and long-term stability are greatly improved, and it can simultaneously realize the construction of the rock during the construction period. The physical stress test and long-term real-time follow-up monitoring during the project operation period fill the industry gap.
Next, the Institute of Rock and Soil Mechanics, Chinese Academy of Sciences researched and developed intelligent mining sites by using next-generation information technologies such as the Internet of Things, smart technologies, cloud computing, and big data as a means of comprehensive perception, real-time transmission, and intelligent online processing. The real-time monitoring system of remote rock 3D stress field has the advantages of automatic monitoring, data sharing and remote control.
Finally, through data mining and intelligent learning of the acquired stress state information, the Wuhan Institute of Rock and Soil Mechanics, Chinese Academy of Sciences established an early warning index and model for dynamic stress risk, which is an early warning, informatization construction of impact rock pressure in the complex environment of underground space and Disaster prevention and mitigation measures provide theoretical and technical support conditions.
The dynamic monitoring and early warning system for rockburst has been verified in many underground projects such as the Dongtan Coal Mine and the Jisan Coal Mine of Yankuang Group, and has gained successful experience and won the second prize for national scientific and technological progress.
This achievement achieved a three-dimensional dynamic long-term test of the stress of the surrounding rock of the stope, which further strengthened the intelligent remote real-time monitoring and early warning research, and solved a major problem for the resource exploitation industry.
(Source: China Energy News, Wuhan Institute of Rock and Soil Mechanics, China Network)
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