摘要
通过三轴卸荷试验,探究了不同路径下卸荷速率对砂岩力学特性及破坏过程中的能量耗散的影响。试验结果表明在全过程应力–应变曲线的弹性阶段,轴向变形起主导作用,弹塑性阶段,环向应变的增加值大于轴向应变增加值。在围压卸荷阶段,卸荷速率越小,卸荷阶段的应变折合柔度越大,此时岩样的变形不充分,呈现明显的脆性破坏。恒主应力差路径下的耗散能大于恒轴压路径下的耗散能的35%,卸荷速率越大,岩样的弹性应变能越小。
The effects of unloading rate under different paths on the mechanical properties of sandstone and the energy dissipation in the failure process have been analyzed by the triaxial unloading test The results are as follows:the axial deformation plays a leading role in the elastic phase of the whole process stress-strain curve.And in the elastoplastic stage,the increase of the hoop strain is greater than the axial strain’s In the confining pressure unloading stage,the smaller the unloading rate,the greater the flexibility of the strain.At the same time,the deformation of the rock sample is insufficient,which is an obvious brittle failure characteristic.The dissipative energy under the constant principal stress difference path is 1.35 times than it is under the constant axial pressure path The larger the unloading rate,the smaller the elastic strain energy of the rock sample.
作者
郭永成
王克辉
胡鹏
刘鑫宇
陈左贵
晏斌
GUO Yongcheng;WANG Kehui;HU Peng;LIU Xinyu;CHEN Zuogui;YAN Bin(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area of Ministry of Education,China Three Gorges University,Yichang 443002,Hubei,China;Hubei Key Laboratory of Disaster Prevention and Mitigation,China Three Gorges University,Yichang 443002,Hubei,China;College of Civil Engineering and Architecture,China Three Gorges University,Yichang 443002,Hubei,China)
出处
《力学与实践》
北大核心
2019年第5期554-558,共5页
Mechanics in Engineering
基金
国家自然科学基金(51439003)
三峡库区地质灾害教育部重点实验室(三峡大学)开放基金(2015KDZ02)
防灾减灾湖北省重点实验室(三峡大学)开放基金(2016KJZ19)
人才科研启动基金(KJ2013B004)资助
关键词
卸荷路径
卸荷速率
能量耗散
应变能
unloading paths
unloading rate
energy dissipation
strain energy
