Acoustic emission characteristics of thermal cracking of marble under uniaxial compression

To investigate the influence of temperature on the characteristics of acoustic emission of rock, the uniaxial compression and acoustic emission tests are conducted on Xuzhou marble at real-time high temperatures（20℃~800℃）and after high temperatures (400℃~800℃). The results show that the marble specimens produce strong acoustic emission signals and become more active as temperature rises in the heating process. The acoustic emission ringing count rate of marble gradually tends to dense, and acoustic emission activity becomes very active near the destruction of samples which reaches the maximum when marble specimens are damaged in the loading process at high temperature. The acoustic emission activity of marble is more frequently at high temperature of 400℃, 600℃ and 800℃ than that after high temperature. The plastic deformation occurs after reaching the peak intensity of marble specimens in which the acoustic emission rate significantly reduces and relatively calm phenomenon appears.