Taking the anthracite of Jincheng coal mine as the research object, the SHPB ( split Hopkinson pressure bar ) dynamic loading system was used to carry out the impact failure of coal sample specimens under different liquid nitrogen freeze-thaw cycles at the same speed, and the fragments were collected for screening test. In order to study the failure characteristics of coal and rock under the impact load of liquid nitrogen freeze-thaw cycle coal sample, the failure mechanism of coal sample system was further clarified. The results show that the particle size distribution of the coal sample is determined by the number of liquid nitrogen freeze-thaw cycles and the physical properties of the medium. When the number of freeze-thaw cycles increases from 0 to 8, the wave velocity decreases by 40% ~ 59%, and the speed attenuation amplitude is positively correlated with the number of freeze-thaw cycles. With the increase of the number of freeze-thaw cycles, the degree of damage of coal samples increases, the number of crushed bodies increases significantly, and the degree of fragmentation of crushed bodies decreases accordingly. Therefore, the degree of damage of coal samples also increases accordingly, and the mass fractal dimension increases from 1.7795 to 1.9121 and tends to be stable, indicating that multiple freeze-thaw cycles promote the uniformity of coal crushing. The research results can provide experimental basis for the stability evaluation and disaster warning of coal body in impact mines in cold regions.
蔡三梅，谢建林，孙晓元，刘雯心. 无烟煤液氮冻融与冲击破坏特征试验研究[J]. 煤炭与化工, 2025, 48(11): 105-110.
Cai Sanmei, Xie Jianlin, Sun Xiaoyuan, Liu Wenxin. Experimental study on freeze-thaw and impact failure characteristics of anthracite liquid nitrogen. CCI, 2025, 48(11): 105-110.
