摘要
岩体的稳定性是深部岩、矿开采过程中重需关注的安全问题,而动力扰动是影响岩体稳定性的重要因素。以双江口水电站深部岩石(花岗岩)为研究对象,对花岗岩进行了室内动静组合加载下的单轴压缩试验,并对岩石破坏后的碎屑粒径、分形维数以及岩石加载过程中的损伤演化进行了分析。得到以下结论:1)随着扰动应力幅值的增大,岩石的碎屑分布越趋于均匀;2)岩石在扰动荷载作用下的碎屑粒径分布满足分形规律,可以用分形维数来表征岩石的破碎程度,且分形维数F与扰动幅值Δσ表现出良好的线性关系,即随着扰动幅值增加,分形维数增大,破碎程度加深;3)扰动荷载作用下,损伤变量呈增大-平稳-增大的变化趋势,且扰动幅值Δσ的大小对岩石平稳区段的循环次数和损伤变化速率存在显著影响。
The stability of rock mass is a serious safety problem in the process of deep rock and mining,and dynamic disturbance is an important factor affecting the stability of rock mass.The deep rock(granite)of Shuangjiangkou Hydropower Station is taken as the research object.The uniaxial compression test of granite under dynamic and static combined loading is carried out in the laboratory,and the particle size,fractal dimension and damage evolution of the rock are analyzed.The results are as follows:(1)with the increase of the amplitude of disturbance stress,the distribution of rock debris tends to be more uniform.(2)The particle size distribution of rock debris under disturbance load meets the fractal law,and the fractal dimension can be used to characterize the degree of rock fragmentation.The fractal dimension F has a good linear relationship with the disturb-ance amplitudeΔσ,that is,with the increase of disturbance amplitude,the fractal dimen-sion increases and the degree of fragmentation deepens.(3)Under the disturbance load,the damage variable has a trend of increasing-stationary-increasing,and the disturbance amplitudeΔσhas a significant influence on the number of cycles and damage change rate of the stationary section of rock.
作者
陈文昭
蒋一凡
刘夕奇
CHEN Wenzhao;JIANG Yifan;LIU Xiqi(School of Civil Engineering,University of South China,Hengyang,Hunan 421001,China;School of Civil Engineering,Wuhan University,Wuhan,Hubei 430000,China)
出处
《南华大学学报（自然科学版）》
2022年第3期47-53,88,共8页
Journal of University of South China：Science and Technology
基金
湖南省教育厅重点科研项目(18A252)。
关键词
花岗岩
循环扰动
应力幅值
分形维数
损伤演化
granite
cyclic disturbance
stress amplitude
fractal dimension
damage evolution
