基于NMR震动载荷作用下含层理煤样损伤演化特征  

Damage evolution characteristics of bedding coal under vibration load based on NMR

作　　者：马衍坤[1,2] 黄勤豪 刘泽伟 柴虎峰 殷志强[1,2] 王超[1,2] 吴昌[3] 潘科举 MA Yankun;HUANG Qinhao;LIU Zewei;CHAI Hufeng;YIN Zhiqiang;WANG Chao;WU Chang;PAN Keju(State Key Laboratory for Safe Mining of Deep Coal Resources and Environment Protection,Anhui University of Science&Technology,Huainan,Anhui 232001,China;Key Laboratory of Safe and Effective Coal Mining Ministry of Education,Anhui University of Science&Technology,Huainan,Anhui 232001,China;Shandong Energy Group Xibei Mining Co Ltd,Xi'an,Shaanxi 710018,China)

机构地区：[1]安徽理工大学深部煤炭安全开采与环境保护全国重点实验室,安徽淮南232001 [2]安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,安徽淮南232001 [3]山东能源集团西北矿业有限公司,陕西西安710018

出　　处：《采矿与安全工程学报》2025年第1期126-136,共11页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(52227901);国家重点研发计划项目(2022YFC3004603);山东能源科技计划重大项目(SNKJ2022A15);安徽省高校杰出青年科研项目(2024AH020001)。

摘　　要：利用分离式霍普金森压杆(SHPB)试验系统,开展了含层理烟煤煤样震动载荷多次冲击试验,借助低场核磁共振分析仪测试每次冲击后煤样的T2谱,并进行核磁共振成像(MRI),研究层理对煤样损伤演化的影响规律。结果表明:层理的存在会劣化煤样承载能力,60°层理煤样能量透射效应最差,吸收的能量主要用于煤样的损伤破坏,此时劣化作用最强;震动载荷多次冲击作用下,煤样微观结构损伤整体呈现出“初始跃进—低速增长—加速上升”3个演化阶段;随着层理角度增大,层理对煤样损伤过程的影响愈发明显,对于0°层理煤样,损伤破坏区沿层理面呈弧形贯通发展趋势,对于30°和60°层理煤样,损伤破坏区沿层理面向煤样两端扩展,对于90°层理煤样,在沿层理面发育的孔裂隙作用下,最终出现复杂交织的损伤破坏区,4种含层理煤样呈现拉伸破坏(0°)—剪切破坏(30°、60°)—混合破坏(90°)的演化趋势。研究成果为揭示震动载荷作用下煤岩动力灾害机制提供了参考。In this study,multiple vibration load impact experiments were carried out on coal samples with bedding by using the split Hopkinson bar(SHPB)test system.Meanwhile,the T2 spectra of these samples after each impact were measured with the aid of a low-field nuclear magnetic resonance(NMR)analyzer,and nuclear magnetic resonance imaging(MRI)was performed.Based on the obtained spectra and images,the effect of bedding on the damage evolution of coal samples was investigated.The following conclusions were drawn.The existence of bedding degrades the bearing capacity of coal samples,and the absorbed energy is mainly used for the damage and destruction of coal samples.The coal sample with 60°bedding witnesses the worst energy transmission effect and the strongest degradation effect.Under the multiple impacts of vibration load,the microstructural damage of coal samples evolves in three stages,i.e.,initial leap,slow growth,and accelerated rise.With the increase of bedding angle,the impact of bedding on the damage process of coal samples becomes more obvious.For the coal sample with 0°bedding,the damage and failure zone presents an arc-shaped penetrated development trend along the bedding plane.For the coal samples with 30°and 60°bedding,the damage and failure zone extends towards both ends of the coal samples along the bedding plane.For the one with 90°bedding,a complex interwoven damage and failure zone eventually appears under the action of pores and fractures developed along the bedding plane.Besides,the four types of bedding coal samples show an evolution trend of tensile failure(0°)-shear failure(30°and 60°)-mixed failure(90°).The research results can be used to reveal the dynamic disaster mechanism of coal rock under the action of vibration loads.

关 键 词：层理煤样 震动载荷 核磁共振(NMR) 损伤演化 

分 类 号：TD324[矿业工程—矿井建设]