摘要
为研究不同围压作用下隧道围岩的破坏机制,以辽宁在建某隧道工程为例,基于能量理论,分析砂岩加载破坏机制。结果表明:随着围压的逐渐增大,砂岩的峰值强度、峰值应变及弹性模量均呈逐渐递增趋势;峰值强度处的总能量、弹性应变能及耗散能同样呈逐渐递增趋势,围压由5 MPa提升至20 MPa,总能量、弹性应变能及耗散能增幅分别为63.73%、47.68%、145.62%,且同一能量值下,围压越大,对应的轴向应变值越大,峰前损伤变量越小;不同围压下砂岩的损伤变形均随轴向应变的增加而逐渐递增,损伤变量与轴向应变二者之间满足指数函数关系,拟合相关系数均大于0.9。
This paper seeks to investigate the failure mechanism underlying tunnel surrounding rock under different confining pressures.The study is focused on analyzing the failure mechanism of sandstone loading by using a tunnel project under construction in Liaoning as an example and based on energy theory.The results show that along with the gradual increase of confining pressure,there is a gradual increase trend in the peak strength,peak strain,and the same gradual increase trend is observed in elastic modulus of sandstone;the total energy,elastic strain energy and dissipation energy at the peak strength,with an increase from 5 MPa to 20 MPa in the pressure and an increase by 63.73%,47.68%,and 145.62%respectively for the total energy,elastic strain energy,and dissipation energy;under the same energy value,the greater confining pressure means the greater corresponding axial strain value,and the peak and smaller front damage variable;and given the increase of the axial strain,there is a gradual increase in the damage and deformation of sandstone under different confining pressures,suggesting that the relationship between the damage variable and the axial strain satisfies an exponential function,with the fitting correlation coefficients all greater than 0.9.
作者
聂宝新
Nie Baoxin(China Railway 19th Bureau Group 3rd Co.Ltd.,Shenyang 110136,China)
出处
《黑龙江科技大学学报》
2021年第6期692-696,752,共6页
Journal of Heilongjiang University of Science And Technology
关键词
隧道
围压
弹性应变能
损伤变量
tunnel
confining pressure
elastic strain energy
damage variable
