1. Key Laboratory of Coal Methane and Fire Control,Ministry of Education,China University of Mining & Technology,Xuzhou　 221116,China; 2. School of Safety Engineering,China University of Mining & Technology,Xuzhou　 221116,China

为提高煤巷工作面突出预测的准确性,对突出预测钻孔常见的喷孔、卡钻等动力现象演化机制进行了研究。首先基于钻孔孔壁位移理论公式探讨了可能导致钻孔失稳破坏的影响因素,进而分析了导致喷孔、卡钻现象出现的原因。然后描述了喷孔现象发生的力学条件及演化过程,并分析了发生卡钻现象的可能类型,利用自主设计的一套能够模拟煤巷现场突出预测的打钻装置,在实验室利用不同煤阶的煤样,使其吸附不同压力的CO2和N2模拟具有不同突出危险性的煤层,并在模拟煤层中施工突出预测钻孔,对喷孔、卡钻等常见动力现象与突出危险性的联系及他们之间的关联进行了研究。结果表明在同等瓦斯压力上升梯度条件下,煤体吸附CO2发生突出的可能性比吸附N2大。随着煤层突出危险性程度的增加,钻屑量会发生突然的增大,同时发生喷孔、卡钻现象的频率增多。预示有突出危险性的卡钻现象往往和喷孔现象是相伴而生的,他们之间构成了联动体系,是相继触发的。

To improve the accuracy of the outburst prediction in working faces of coal roadways,the evolution mecha- nism of the dynamic phenomena such as gas and coal being ejected from the borehole ( GCEB) and drill pipe being stuck by coal mass in the borehole (DPSC)) were studied. Firstly,based on the theoretical formula of borehole wall displacement,the factors that affect the instability failure of borehole and the causes of occurrence for the GCEB and DPSC were discussed. Then the mechanical conditions and evolutionary process for the occurrence of GCEB were de- scribed,while the possible types of DPSC were analyzed. A self-designed drilling device that can simulate the in-situ outburst prediction of coal roadways was used in this study. The coal samples with different coal ranks to adsorb CO2 and N2 with different pressures in the laboratory were used to simulate the coal seams with different outburst risks. In addition,the boreholes for predicting the outburst were drilled in the simulated coal seams to study the correlation between common dynamic phenomena and outburst risks. The results show that under the same rising gradient of gas pressures,the occurrence possibility of outburst caused by coal masses adsorbing CO2 is larger than that of adsorbing N2 . When the coal seams without outburst risks change into ones with outburst risks,drilling cutting weight generally increase all of a sudden and the occurring frequency of GCEB and DPSC increase. The DPSC phenomenon indicating outburst risks is generally accompanied with GCEB,which form a linkage system and are triggered successively.

江苏省自然科学基金资助项目(BK20150195)；江苏省普通高校研究生科研创新计划资助项目(KYLX15_1431)；

WANG Chaojie,YANG Shengqiang,JIANG Chenglin,et al. Mechanism of dynamic phenomena of borehole for outburst prediction and their relationship during coal roadway driving[J]. Journal of China Coal Society,2017,42(9):2327-2336.