文献类型：期刊文献

英文题名：Experimental study of rock burst in coal samples under overstress and true-triaxial unloading through passive velocity tomography

作者：Zhu, Guang-an[1,2];Dou, Lin-ming[3];Wang, Chang-bin[4];Ding, Zi-wei[1];Feng, Ze-jie[1];Xue, Fei[2]

机构：[1]Xian Univ Sci & Technol, Sch Energy Engn, Xian 710054, Shanxi, Peoples R China;[2]Shaoxing Univ, Ctr Rock Mech & Geohazards, Shaoxing 312000, Zhejiang, Peoples R China;[3]China Univ Min & Technol, Sch Mines, Key Lab Deep Coal Resource Min, Minist Educ China, Xuzhou 221116, Jiangsu, Peoples R China;[4]Univ New South Wales, Sch Minerals & Energy Resources Engn, Sydney, NSW 2052, Australia

年份：2019

卷号：117

起止页码：388

外文期刊名：SAFETY SCIENCE

收录：SCI-EXPANDED(收录号：WOS:000474322600039)、、EI(收录号：20191906882445)、Scopus(收录号：2-s2.0-85065101204)、WOS

基金：This work was supported and financed by the Outstanding Youth Science Foundation of Xi'an University of Science and Technology (Grant No. 2018YQ3-01), the Doctoral Scientific Research Foundation of Xi'an University of Science and Technology (Grant No. 2017QDJ058), the Zhejiang Collaborative Innovation Center for Prevention and Control of Mountain Geologic Hazards (Grants No. PCMGH-2017-Y02 and PCMGH-2016-Y-05), the China Postdoctoral Science Foundation (Grant No. 2018M643692), the Scientific Research Program Funded by Shaanxi Provincial Education Department (Grand No. 18JK0497) and the National Natural Science Foundation of China (Grant no. 51874232).

语种：英文

外文关键词：Overstressed coal mass; Rock burst; True-triaxial unloading process; Acoustic emission; Passive velocity tomography

外文摘要：The influence of overstress state on rockbursts in deep underground coal mining was investigated. Laboratory experiments were conducted using a true-triaxial rockburst system. Passive velocity tomography, using acoustic emission (AE), was used to study the internal microfractures and energy evolution of coal samples during true-triaxial compression. AE activities were monitored using eight sensors and every 130 consecutive AE events were used for tomographic calculations. For each coal sample, three phases and between four and six typical tomography results were obtained which reflected significant variations in velocity redistribution. Experimental results show that there was a significant time-delay effect under different loading and unloading stress paths. Compared to triaxial loading, coal samples are more easy to deform and bring to failure under triaxial unloading. Under a constant confining pressure, bursting failure occurs when the axial stress is more than three times the uniaxial compressive strength of the coal sample. The wave velocity inversion results show that the macrofracture positions in coal samples after failure have a positive correlation with the region of wave velocity anomalies, and the low wave velocity zone corresponds to areas of microfracture evolution.