摘要
利用微机伺服岩石三轴试验机TAW-2000,对泥岩进行了不同围压(σ3=0.5 MPa、2 MPa)和加载频率(f=0.2 Hz~2 Hz)下的变幅循环荷载试验,研究了围压、加载频率及加载幅值对泥岩的破坏形式、动抗压强度、滞回曲线面积及动弹性模量(Ed)的影响。试验结果表明:在0.2 Hz~2 Hz的加载频率下,岩石破坏形式受围压影响较大,以剪切破坏为主,部分岩样出现劈裂破坏;在0.2 Hz~1 Hz的加载频率和0.5 MPa~1 MPa的围压下,动抗压强度主要呈现减小趋势,仅在2 Hz的加载频率下,岩石抗压强度有较大提高;滞回曲线面积随加载幅值增加逐渐增加,同一幅值作用下,滞回曲线面积随循环次数的增加呈现减小趋势;Ed随加载幅值增加而减小后趋于稳定。
The variable amplitude cyclic loading tests of mudstone under different confining pressures(σ3=0.5 MPa,2 MPa)and loading frequencies(f=0.2-2 Hz)were carried out by using microcomputer servo rock triaxial testing machine TAW-2000,the effects of confining pressure,loading frequency and loading amplitude on the failure mode,dynamic compressive strength,hysteretic curve area and dynamic elastic modulus of mudstone are studied.The test results show that under the loading frequency of 0.2-2 Hz,the rock failure mode is greatly affected by the confining pressure,mainly shear failure,and split failure occurs in some rock samples.Under the loading frequency of 0.2-1 Hz and the confining pressure of 0.5-1 MPa,the dynamic compressive strength mainly shows a decreasing trend.Only at the loading frequency of 2 Hz,the compressive strength of the rock is greatly improved.The area of the hysteresis curve gradually increases with the increase of the loading amplitude.Under the same amplitude,the area of the hysteresis curve decreases with the increase of the number of cycles.Ed decreases with the increase of loading amplitude and then tends to be stable.
作者
龙慧
刘书文
庄轲
梁海安
LONG Hui;LIU Shuwen;ZHUANG Ke;LIANG Haian(School of Civil Engineering, University of South China, Hengyang, Hunan 421001, China;College of Architectural Engineering, East China University of Technology, Nanchang, Jiangxi 330013, China)
出处
《南华大学学报（自然科学版）》
2021年第4期35-40,共6页
Journal of University of South China：Science and Technology
基金
国家自然科学基金青年基金项目(51708273)
湖南省自然科学基金青年基金项目(2017JJ3263)。
关键词
动力特性
变幅循环荷载
加载频率
围压
dynamic characteristics
variable amplitude cyclic load
loading frequency
confining pressure
