温度冲击作用下煤的渗透率变化规律与增透机制

发布时间：2018-05-19 16:23

本文选题：温度冲击 + 裂隙扩展　；参考：《煤炭学报》2017年08期

【摘要】：为了研究温度冲击条件下的煤体渗透性变化规律及增透机制,利用恒温箱和液氮对原煤煤样进行了两种条件下的温度冲击试验,分析了煤样在温度冲击前后的渗透率变化情况和微观裂隙发育情况,探讨了温度冲击过程中的声发射信号分布规律。试验结果表明:在经过冷冲击处理和热-冷冲击处理后,煤体的渗透率平均增幅分别为48.68%和469.24%,热-冷冲击处理过程中煤样的声发射能量峰值是冷冲击处理过程中煤样的声发射能量峰值的3.6倍,相比冷冲击处理,热-冷处理所产生的微裂纹数量更多,裂隙呈树枝状发育,增透效果更好;煤体性质的各向异性和温度冲击所产生的超过煤体抗拉强度的热应力是主要的增透机制。
[Abstract]:In order to study the change law of coal permeability and antireflection mechanism under the condition of temperature shock, the temperature shock tests of raw coal samples were carried out under two conditions by using constant temperature box and liquid nitrogen. The change of permeability and the development of microcracks in coal samples before and after temperature shock are analyzed, and the distribution of acoustic emission signals during temperature shock is discussed. The results show that after cold shock treatment and hot cold impact treatment, The average increase of coal permeability is 48.68% and 469.24%, respectively. The peak value of acoustic emission energy of coal sample during hot and cold impact treatment is 3.6 times that of coal sample during cold impact treatment, compared with that of cold impact treatment, the average increase of coal permeability is 48.68% and 469.24%, respectively. The microcracks produced by thermo-cold treatment are more numerous, the cracks are dendritic, and the antireflection effect is better. The main antireflection mechanism is the anisotropy of coal properties and the thermal stress which exceeds the tensile strength of coal due to the anisotropy of coal properties and the temperature shock.
【作者单位】：河南理工大学河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地;河南理工大学安全科学与工程学院;煤炭安全生产河南省协同创新中心;
【基金】：国家自然科学基金资助项目(51574112,51404100) 河南省科技创新杰出青年基金资助项目(164100510013)
【分类号】：TD712

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