岩性对I型裂纹定向扩展规律影响的试验研究
Experimental study on influence of lithology on directional propagation law of type-I cracks
陈玏昕 1郭伟耀 2蒋宇静 3谭彦 1张悦颖 1卢丹 1韩飞4
作者信息
- 1. College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China
- 2. College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Graduate School of Engineering,Nagasaki University,Nagasaki 852-8521,Japan
- 3. Graduate School of Engineering,Nagasaki University,Nagasaki 852-8521,Japan
- 4. Research Center for Rockburst Prevention and Control,Shandong Energy Group Co.,Ltd.,Jinan 250014,China
- 折叠
摘要
为揭示岩性对岩石I型裂纹定向扩展的影响规律,采用一种简易裂纹定向扩展装置开展白砂岩、灰砂岩和大理岩3类典型岩石加载试验,研究不同类型岩石I型裂纹定向扩展过程中变形场及声发射演化特征,探讨岩性影响下I型裂纹扩展机制.研究结果表明:白砂岩峰后荷载曲线呈平缓降低趋势,而大理岩和灰砂岩峰后曲线则呈陡降趋势,且其断面平整度高于白砂岩的,脆性断裂特征更为显著;根据水平位移场演化规律,可将岩石I型裂纹扩展过程划分为弹性变形、微裂纹集结成核和裂纹起裂扩展3个阶段,而白砂岩进入微裂纹集结成核阶段则远早于大理岩和灰砂岩;岩石I型裂纹扩展全过程中声发射演化可划分为平静期、活跃期、突增期和回落期4个阶段,其中白砂岩的平静期、活跃期及突增期持续时间短、回落期持续时间长,而大理岩和灰砂岩则与之相反;岩石I型裂纹扩展的本质是断裂过程区孕育过程,由于白砂岩断裂过程区长度大于大理岩和灰砂岩的,造成其裂纹定向扩展速度及稳定程度均低于其他两类岩石.
Abstract
To study the influence of lithology on the directional propagation law of rock type-Ⅰ cracks,a simple crack directional propagation device was used to conduct loading tests on three rock types.The acoustic emission(AE)and displacement field characteristics during crack directional propagation were analyzed,and the propagation mechanism of type-Ⅰ cracks was discussed.The results indicate that the post-peak load curve of white sandstone showed a gradually decreasing trend,while marble and grey sandstone showed a steep decreasing trend.The AE evolution during crack propagation can be divided into four stages:quiet,slowly increasing,booming,and decreasing.For white sandstone,the duration of the first three stages was short,and the decreasing stage was long.However,the opposite trend was observed for the other types.The crack propagation process includes three stages based on the evolution law of the horizontal displacement field:elastic deformation,microcrack nucleation and coalescence,and crack initiation and propagation.The white sandstone enters the microcrack nucleation and coalescence stage earlier than marble and grey sandstone.The length of the fracture process zone of white sandstone was larger than that of marble and grey sandstone;thus,its crack directional propagation rate and stability were lower.
关键词
岩性/Ⅰ型裂纹/数字图像/位移场/声发射/扩展机制Key words
lithology/type-Ⅰ crack/digital image correlation(DIC)/displacement field/acoustic emission(AE)/propagation mechanism引用本文复制引用
基金项目
国家自然科学基金(52274086)
山东省自然科学基金重大项目(ZR2019ZD13)
Education System Government Sponsored Study Abroad Program of Shandong Province,China()
出版年
2023
NETL
NSTL
万方数据