Yu Yongjiang, Dong Xu, Liu Jiaming, Song Zhiyuan, Wu Zhiqiang, Guo Wenjing
College of Mining, Liaoning Technical University, Fuxin, 123000, Liaoning, China.
Sci Rep. 2025 Jan 23;15(1):3001. doi: 10.1038/s41598-025-87373-1.
With increasing mining depth, the coal pillars of a coal mine will be in a stressful environment characterized by high gas pressures and unidirectional loading. To investigate the damage evolution characteristics and energy evolution mechanism of coal pillars loaded in a gas pressure environment, a uniaxial compression test was performed on a coal body under different gas pressures using a load testing apparatus for gas-containing coal rocks. The obtained results showed that the mechanical properties of the coal body varied with the gas pressure. Specifically, the peak strain, compressive strength, and elastic modulus decreased with increasing gas pressure; the higher the gas pressure, the lower the conversion rate of the elastic strain energy in the elastic deformation stage of the coal body and the lower its total input energy. With increasing gas pressure, the damage threshold of the coal body decreased, whereas the damage variable corresponding to the peak value, as well as the damage threshold value, increased. According to the theory of continuous damage mechanics, an ontological damage model of the coal body under different gas pressures was established based on the principle of minimum energy dissipation, and the rationality of the model was verified through a comparison between the theoretical and experimental data. Our findings can be useful in ensuring the safety of coal mining in terms of preventing gas disasters.
随着开采深度的增加，煤矿煤柱将处于高瓦斯压力和单向加载的应力环境中。为了研究瓦斯压力环境下煤柱的损伤演化特性和能量演化机制，利用含瓦斯煤岩加载试验装置对不同瓦斯压力下的煤体进行了单轴压缩试验。试验结果表明，煤体的力学性能随瓦斯压力的变化而变化。具体而言，峰值应变、抗压强度和弹性模量随瓦斯压力的增加而降低；瓦斯压力越高，煤体弹性变形阶段弹性应变能的转化率越低，其总输入能量也越低。随着瓦斯压力的增加，煤体的损伤阈值降低，而对应峰值的损伤变量以及损伤阈值均增大。根据连续损伤力学理论，基于能量耗散最小原理建立了不同瓦斯压力下煤体的本体损伤模型，并通过理论数据与试验数据的对比验证了模型的合理性。我们的研究结果对于预防瓦斯灾害，确保煤矿开采安全具有重要意义。
