Experimental and theoretical study on the dynamic effective stress of loaded gassy coal during gas release

作     者：Bing Zhang Hanpeng Wang Peng Wang Guofeng Yu Shitan Gu Bing Zhang;Hanpeng Wang;Peng Wang;Guofeng Yu;Shitan Gu

作者机构：School of Qilu TransportationShandong UniversityJinan 250061China Geotechnical and Structural Engineering Research CenterShandong UniversityJinan 250061China Coal Mining National Engineering Technology Research InstituteHuainan 232001China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and TechnologyShandong University of Science and TechnologyQingdao 266590China 

出 版 物：《International Journal of Mining Science and Technology》 (矿业科学技术学报（英文版）)

年 卷 期：2023年第33卷第3期

页      面：339-349页

核心收录：

学科分类：0819[工学-矿业工程] 081903[工学-安全技术及工程] 0817[工学-化学工程与技术] 08[工学] 0818[工学-地质资源与地质工程] 0703[理学-化学] 

基　　金：This research was funded by the National Natural Science Foundation of China(No.52174081) the China Postdoctoral Science Foundation(No.2021M702001) the Postdoctoral Innovation Project of Shandong Province(No.202102002) the Natural Science Foundation of Shandong Province(No.2019GSF111036) 

主　　题：Gassy coal Dynamic effective stress Gas release Gas-solid coupling Mathematical model 

摘      要：In the process of mining coalbed methane(CBM),an unsteady state often arises due to the rapid extraction,release and pressure relief of *** this case,the effective stress of coal changes dynamically,affecting the stability of the gassy coal *** this paper,gas release tests of gassy coal under conventional triaxial compression were performed,and the dynamic effective stress(DES)during gas release was obtained indirectly based on a constitutive equation and deformation of *** results show that the maximum increases in DES caused by the release of free gas and adsorbed gas under the stress of 1.1 MPa were 0.811 and 5.418 MPa,respectively,which seriously affected the stress state of the *** the gas release,the free gas pressure and the adsorbed gas volume were the parameters that directly affected the DES and showed a positive linear relationship with the DES with an intercept of *** DES of the coal sample increased exponentially with time,which was determined by the contents of free and adsorbed *** on the experimental results and theoretical analysis,an effective stress model was obtained for loaded gassy coal during gas *** results of verification indicated accuracy greater than 99%.