Study on Precursor of Infrared Temperature Critical Slowing in Coal Sample Uniaxial Compression Failure

To study the effective precursor information of the coal sample under loading and damage process, we carried out the uniaxial compression loading experiment of coal sample, analyzed the infrared radiation temperature variation characteristics of the coal sample under the same loading mode, and applied the critical slowing theory to the highest infrared radiation of the coal sample. The temperature was processed, the variance and autocorrelation coefficient of the highest infrared radiation temperature were compared, and the variance, the highest infrared radiation temperature and the variation of the load in time were analyzed. The results show that the highest and average infrared temperature trends of coal samples in the early and middle loading period are basically the same. The highest infrared temperature in the late stage of loading shows an upward trend at the damage point of coal samples. When the main rupture occurs, the highest infrared radiation temperature rises sharply. The average infrared temperature did not show significant changes at the main rupture; the variance and autocorrelation coefficients were affected by the window length and the lag step, but the variance curve was greatly affected by the window length; the contrast infrared precipitation precursor and the infrared temperature rise the increase point, the variance is more accurate in predicting the instability of coal samples.