Study on the characteristics of EMR signals induced from fracture of rock samples and their application in rockburst prediction in a copper mine

摘要

Rockbursts pose a serious threat to safety during underground excavating or engineering, andcan result in structural damage and personnel casualties. The frequency and severity ofrockbursts increase with increasing mining depth. Several rockburst disasters have occurredin Hongtoushan copper mine, the depth of which exceeds 1000 m, and rockburst predictionand control is therefore an important underground engineering function. In this investigation,rock samples from the mine were deformed and fractured under uniaxial compression,tension, and cyclic loading and the characteristics of the electromagnetic radiation (EMR)signals generated were studied. A high correlation was found between EMR intensity, pulse,and frequency and the loading or stress. Based on the experimental results, EMR monitoringequipment of KBD5 type was developed and used to monitor EMR signals generated by therock mass in the mining area in Hongtoushan copper mine. From the test results, we deriveda generic model of how EMR characteristics respond to changes in mining-induced stressand stress concentration, and propose an EMR-based for providing early warning ofrockbursts.