Acoustic monitoring method for rock burst risk of coal mine tunnel

Abstract

The invention discloses an acoustic monitoring method for rock burst risks of a coal mine tunnel. The acoustic monitoring method comprises the steps of: transmitting a characteristic vibration wave signal to a coal mass through setting a vibration exciter, picking up vibration waves propagated in the coal mass by setting detectors, and calculating a longitudinal wave velocity of the coal mass between two adjacent detectors according to a first arrival time difference; and calculating a change rate of a longitudinal wave velocity in a corresponding coal mass region along with the advancing of a stope face during the coal mining process, calculating a corresponding rock burst risk index according to a logarithmic relationship between the coal rock burst risk and the change rate of the longitudinal wave velocity, and grading the rock burst risk index. The acoustic monitoring method can determine rock burst risk regions and risk levels precisely, is simple in operation and low in cost, has good applicability, and is of great significance in selecting reasonable prevention and control measures and guaranteeing safe and efficient mining of the working face.

Description

technical field [0001] The invention relates to a method for monitoring the risk of rock burst, in particular to an acoustic monitoring method for the risk of rock burst in a roadway during the mining process of a coal mine working face. Background technique [0002] Rock burst is one of the most common dynamic disasters in coal mining. It is caused by the rapid release of a large amount of elastic deformation energy accumulated in coal and rock mass. There is generally no obvious macroscopic omen before the occurrence. With the increase of mining depth, the impact Ground pressure disasters are becoming more and more serious, especially in the vicinity of mining roadways, which account for about 80% of the occurrences, which will cause serious consequences such as coal and rock mass damage rushing out and blocking the roadway, casualties, equipment damage, etc., and may also induce gas outbursts and water inrush. Therefore, real-time and accurate monitoring of the risk level...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used methods for monitoring the risk of rock burst mainly include drilling cuttings method, electromagnetic radiation method, microseismic method, wave velocity gradient method, etc., but the monitoring data of electromagnetic radiation method and microseismic method are easily disturbed, imprecise, and the equipment cost is high; The drilling cuttings method can only monitor the danger of local points, but cannot monitor the entire coal body in real time; the wave velocity gradient method cannot accurately determine the location and grade of rock burst

Images