摘要
为研究加载应变率对硬岩的力学性质与能量吸收、储存和耗散的影响,本文对砂岩试样开展了不同应变率下的单轴压缩试验,试验结果表明砂岩试样的峰值应力、峰值应变和弹性模量均随着加载应变率的增大而增大,但加载应变率对砂岩试样的单轴抗压强度影响显著。研究了砂岩试验在不同阶段变形过程中的能量吸收与耗散规律,得到了砂岩试样在变形前期以弹性应变能的形式储存能量,同时又以损伤演化等耗散能量,在变形后期以剧烈地释放能量为主,且加载应变率越大,能量释放率越快。研究结果表明能量耗散是导致砂岩试样强度降低的本质原因,基于能量耗散与裂纹损伤之间的内在联系,得到了加载应变率越大砂岩试样的损伤应力比、损伤应变与损伤应力也越大。从能量吸收与耗散的角度研究硬岩损伤破裂规律,可从本质上揭示硬岩在外荷载作用下的变形破坏机制,可为实际工程提供参考。
In order to study the effect of loading strain rate on mechanical properties and energy absorption,storage and dissipation of hard rock,uniaxial compression tests on sandstone samples under different strain rates were carried out in this paper.The experiment results show that the peak stress,peak strain and elastic modulus of sandstone samples all increase with the increase of loading strain rate,but the loading strain rate has a significant effect on the uniaxial compressive strength.The law of energy absorption and dissipation during the deformation of sandstone in different stages is studied,and it is obtained that the sandstone samples store energy in the form of elastic strain energy in the early deformation stage.Meanwhile,the energy is dissipated by damage evolution,the energy is mainly released violently at the later stage of deformation,and the higher the loading strain rate,the faster the energy release rate.The results show that energy dissipation is the essential reason for the strength reduction of sandstone samples,based on the internal relationship between energy dissipation and crack damage,it is concluded that the damage stress ratio,damage strain and damage stress of sandstone sample increase with the increase of loading strain rate.Studying the damage and fracture law of hard rock from the energy absorption and dissipation can reveal the deformation and failure mechanism of hard rock under external load in essence and provide reference for practical engineering.
作者
党亚倩
王团结
汪洪菊
吴亚敏
梁玉晴
DANG Yaqian;WANG Tuanjie;WANG Hongju;WU Yamin;LIANG Yuqing(School of Architectural Engineering,Zhengzhou University of Industrial Technology,Xinzheng 451100,China;College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China;China Construction Seventh Engineering Division Co.,Ltd.,Zhengzhou 450000,China)
出处
《金属矿山》
CAS
北大核心
2022年第12期45-51,共7页
Metal Mine
基金
中建七局科技研发课题(编号:JTZB-TJDT-D011/2022)
中建七局科技计划项目(编号:YIJC-HLGS-D140/2021)。
关键词
硬岩
单轴压缩
应变率
力学性质
能量
hard rock
uniaxial compression
strain rate
mechanical properties
energy
