摘要
为研究主、次裂隙在近似T型分布下对岩石变形破坏机制的影响,基于含主、次裂隙类岩石试件的单轴压缩试验及线弹性断裂力学理论,研究了轴向压缩下由夹角变化引起裂隙岩石中主、次裂隙应力场的变化规律,并进一步探究了其对岩石强度与变形特征的影响。研究结果表明:次裂隙的存在对单一裂隙试件的强度特征有明显影响,含次裂隙试件强度降至单一裂隙试件的30. 2%～47. 5%;裂隙夹角由30°增加至60°时引起主裂隙相交节点两侧剪应力方向由同向转变为异向,由应力的叠加转变为应力的抵消,对裂隙岩石的破坏过程产生抑制作用,从而增强岩石的峰值强度;相较于裂隙间应力场的相互影响,新增裂隙数量所增加的能量消耗引起的强度特征变化更为显著。
In order to study the influence of primary and secondary fractures on the deformation and failure mechanism of rock under the approximate T-shaped distribution,based on the uniaxial compression tests of the rock-like specimens containing primary and secondary fractures and the theory of linear elastic fracture mechanics,the variation of stress field of the primary and secondary fractures in the fractured rock caused by the change of angle under the axial compression was studied,and its influence on the strength and deformation characteristics of rock was further explored.The results showed that the existence of secondary fracture had significant effect on the strength characteristics of specimen with single fracture,and the strength of specimens with secondary fracture reduced to 30.2%-47.5% of that of specimen with single fracture.When the angle of fractures increased from 30° to 60°,the direction of shear stress on both sides of the intersection of primary fractures changed from the same direction to different directions,and the superposition of stress transformed into the offset of stress,which inhibited the failure process of fractured rock and enhanced the peak strength of rock.Compared with the interaction of stress field between the fractures,the change of strength characteristics caused by the added energy consumption due to the adding amount of fractures was more significant.
作者
李克钢
王庭
秦庆词
潘震
黄伟
杨宝威
LI Kegang;WANG Ting;QIN Qingci;PAN Zhen;HUANG Wei;YANG Baowei(Faculty of Land Resource Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China)
出处
《中国安全生产科学技术》
CAS
CSCD
北大核心
2019年第2期181-186,共6页
Journal of Safety Science and Technology
基金
国家自然科学基金项目(41672303)
关键词
近似T型裂隙
单轴压缩
类岩石材料
强度特征
approximate T-shaped fracture
uniaxial compression
rock-like material
strength characteristic
