Abstract The rockburst of granite in roadway due to tectonic stress was studied experimentally and numerically. The intrinsic links among the visible light images,the acoustic emissions(AE) and the far-infrared radiations were investigated to reveal the characteristics and mechanisms of rockburst in roadway. The proneness index of rockburst of granite was found to have moderate values from 13.84 to 18.02. The physical parameters changed suddenly and greatly just prior to the occurring of rockburst due to energy dissipation. Debris were ejected out from the two sides of the tunnel. The higher the side pressure is,the stronger the rockburst is. There are at least two temperature jumps,one is the initial temperature anomaly and the other is at omen point of rockburst. The leap of b-value and the occurrence of a quiet period of AE is the precursor of large fracturing. In virtue of the results of statistical analysis,the sensitivity to rockburst of three monitoring methods,visible image,far infrared and AE are found to be in declining order. A variety of ways of monitoring the multiple physical parameters are required to provide more accurate early warning information of rockburst on account of the complexities of internal observations with the imaging method of visible light.
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