摘要
综合采用裂纹体积应变法和声发射法分析了煤储集层起裂强度、损伤强度、破坏模式和声发射特征的各向异性特征。研究表明,煤储集层抗压强度、起裂强度和损伤强度均表现出明显的各向异性特征,抗压强度随层理倾角的增加而减小,但层理倾角为45°与90°时抗压强度相差不大,起裂和损伤强度均随层理倾角的增加先减小后增大,层理倾角为0°时起裂和损伤强度最高,90°时次之,45°时最低;层理倾角为0°时煤储集层破坏模式为大尺度破裂的稳步扩展,层理倾角为45°时部分为小尺度破裂稳步扩展,部分为大尺度破裂的突发式失稳扩展,层理倾角为90°时主要为小尺度破裂的突发式失稳破坏;与声发射计数相比,声发射能量更适合用来确定煤储集层的起裂和损伤强度。
The crack volume strain method and acoustic emission(AE)method are used to analyze the anisotropy of the crack initiation strength,damage strength,the failure mode and the AE characteristics of coal reservoir.The results show that coal reservoirs show obvious anisotropic characteristics in compressive strength,cracking initiation strength and damage strength.The compressive strength of coal reservoirs decreases with the increase of bedding angle,but the reservoirs with bedding angles of 45°and 90°differ little in compressive strength.The crack initiation strength and damage strength decrease first and then increase with the increase of bedding angle.The crack initiation strength and damage strength are the highest,at the bedding angle of 0°,moderate at the bedding angle of 90°,and lowest at the bedding angle of 45°.When the bedding angle is 0°,the failure of the coal reservoirs is mainly steady propagation of large-scale fractures.When the bedding angle is 45°,one type of failure is caused by steady propagation of small-scale fractures,and the other type of failure is due to a sudden instability of large-scale fractures.When the bedding angle is 90°,the failure is mainly demonstrated by a sudden-instability of small-scale fractures.Compared with the cumulative count method of the AE,the cumulative energy method is more suitable for determining crack initiation strength and damage strength of coal reservoirs.
作者
郝宪杰
魏英楠
杨科
苏健
孙英峰
朱广沛
王少华
陈海波
孙卓文
HAO Xianjie;WEI Yingnan;YANG Ke;SU Jian;SUN Yingfeng;ZHU Guangpei;WANG Shaohua;CHEN Haibo;SUN Zhuowen(School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,China University of Mining and Technology(Beijing),Beijing 100083,China;State Key Laboratory of Water Resource Protection and Utilization in Coal Mining,Beijing 100083,China;Key Laboratory of Safety and High-efficiency Coal Mining,Ministry of Education(Anhui University of Science and Technology),Huainan 232001,China;State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;College of Engineering,Peking University,Beijing 100083,China;CAS Key Laboratory of Mechanical Behaviour and Design of Materials,University of Science and Technology of China,Hefei 230026,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2021年第1期211-221,共11页
Petroleum Exploration and Development
基金
国家自然科学基金(51804309,51861145403)
煤炭开采水资源保护与利用国家重点实验室开放基金(SHJT-17-42.10)
中国科协青年人才托举工程(2017QNRC001)
深部煤矿采动响应与灾害防控国家重点实验室开放基金(JYBSYS2018201)。
关键词
煤层气
煤储集层
起裂强度
损伤强度
水力压裂
层理
裂纹体积应变
声发射
coalbed methane
coal reservoir
crack initiation strength
damage strength
hydraulic fracturing
bedding
crack volume strain
acoustic emission
