Experimental study on AE characteristics of cemented tailings backfill failure process with different concentration
ZHAO Kui;XIE Wenjian;ZENG Peng;GONG Cong;ZHUO Yulong;YU Xinjia;YANG Zeyuan;LIU Zhouchao;College of Resources and Environmental Engineering, Jiangxi University of Science and Technology;Key Laboratory of Mining Engineering of Jiangxi Province, Jiangxi University of Science and Technology;
Three kinds of backfill samples with different mass concentrations were prepared, and the uniaxial compression acoustic emission(AE) test was carried out. The mechanical properties of backfill with different mass concentrations were analyzed, focusing on the characteristics of the AE ring count, the ratio of AE cumulative hit number to AE cumulative energy(r value), the main frequency and its relative high frequency signal surge response coefficient. The results show that: with the increase of the concentration, the peak strength and modulus of elasticity of the backfill increase, and the more the cumulative AE ring count appear in the backfill; the r value increases first and then continuously decreases to a lower value, and with the increase of the external load, it enters a slowly increasing stage, and which remains at this stage before the peak value. In the distribution of the main frequency of AE signal, the precursory information of backfill fracture appears the phenomenon of increasing the main frequency segment, which is represented by 1 ～2 main frequency segments in the initial loading stage and 3 ～ 5 main frequency segments in the critical main fracture stage. With the increase of concentration, the main frequency segment of AE signal is wider, and the surge response coefficient of AE relative high frequency signal(160 ～180 kHz) is decreasing. The above characteristics can provide a basis for the stability monitoring and early predicting of different concentrations of cemented tailings backfill.