摘要
为了研究层状岩体在巴西劈裂条件下的破坏力学行为,建立基于颗粒离散元的层状岩体数值模型,采用基于矩张量理论的声发射计算方法,对层状岩体巴西劈裂条件下的声发射规律进行分析。研究结果表明:同一角度下,岩体的劈裂强度随着层理面强度的增加而增加。当层理面的强度值与岩石基质体相当时,岩石表现出各向同性的特点;当层理面强度小于岩石基质时,岩石的劈裂强度随着角度的变化呈现出“U”形分布的特点。各种工况下,拉裂纹的占比均大于剪切裂纹的占比,说明拉伸破裂是岩石微观破裂的主要类型。各种工况下,岩石的矩张量值主要分布在-5.75~-5.0之间,且峰值出现在-5.5~-5.25区间。声发射事件的矩张量大小与其数量之间的关系大致服从正态分布。随着层理面强度的减小,b值大致呈现出增加的趋势,说明声发射能量较小的事件在岩石层理面强度较小时占比较大。
A numerical model of layered rock mass based on particle discrete element is established in order to study the failure mechanical behavior of layered rock mass under Brazilian splitting condition.In the study,the acoustic emission calculation method based on moment tensor theory is used to analyze the acoustic emission law of layered rock mass under Brazilian splitting condition.The results show that the splitting strength of rock mass increases with the increase of bedding plane strength at the same angle.When the strength of bedding plane is equal to that of rock matrix,the rock shows isotropy,while the strength of bedding plane is smaller than that of rock matrix and the splitting strength of rock presents a U-shaped distribution with the change of angle.The proportion of tensile crack is larger than that of shear crack under various working conditions,indicating that tensile fracture is the main type of rock micro-fractures.Under various working conditions,the moment tensor values of rocks are mainly distributed between-5.75 and-5.0,and the peak values appear in the range of-5.5 to-5.25.The relationship between the moment tensor and the number of acoustic emission events generally follows the normal distribution.With the decrease of bedding plane strength,b value shows an increasing trend,indicating that the events with low acoustic emission energy account for a large proportion of the rock bedding plane strength.
作者
万宇
林宇
丁尧
王俊
李化云
徐国文
雷中成
陈晔磊
WAN Yu;LIN Yu;DING Yao;WANG Jun;LI Huayun;XU Guowen;LEI Zhongcheng;CHEN Yelei(School of Civil Engineering, Architecture and Environment, Xihua University, Chengdu 610039, China;College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu 610059, China;Sichuan Highway Planning, Survey, Design and Research Institute Ltd., Chengdu 610041, China;China Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China)
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2021年第6期714-722,共9页
Journal of Chengdu University of Technology: Science & Technology Edition
基金
四川省科技计划项目(2021YJ0542)。
关键词
颗粒离散元
层状岩体
巴西劈裂
矩张量
声发射
discrete element method
layered rock
Brazilian splitting
moment tensor
acoustic emission
