爆破引起的深埋岩石隧道动态应力集中和破坏特征
Blasting induced dynamic stress concentration and failure characteristics of deep-buried rock tunnel
赵瑞 1陶明 1向恭梁 1王少锋 1赵华涛2
作者信息
- 1. School of Resources and Safety Engineering,Central South University,Changsha 410083,China
- 2. School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China
- 折叠
摘要
本文利用复变函数法和杜哈梅尔积分法对直墙拱隧道(SWAT)周围的动态应力集中系数(DSCF)进行了理论求解,分析了波长、入射角和爆破上升时间对DSCF分布的影响.理论结果表明,动态扰动导致垂直方向的压应力集中和入射方向的拉应力集中.随着波长和上升时间的增加,应力集中的幅值有先上升后收敛的趋势.此外,利用LS-DYNA和显式隐式转换方法求解了一系列三维有限元模型,评估了不同初始应力状态对隧道围岩动态破坏的影响.结果表明,围岩的破坏受静态最大主应力方向和动态扰动方向的显著影响.在静载荷和爆破载荷的耦合作用下,隧道周围的破坏更容易发生在动静应力集中重合区.总结了岩石隧道在不同方向的静应力和爆破扰动作用下的破坏模式,并提出了相应的建议支护体系,结果揭示了深埋岩石隧道破坏和动态触发岩爆的机理.
Abstract
In this study,the dynamic stress concentration factors(DSCF)around a straight-wall arch tunnel(SWAT)were solved analytically utilizing the complex variable function methods and Duhamel's integral.The effects of wavelength,incident angle,and blasting rising time on the DSCF distribution were analyzed.Theoretical results pointed out dynamic disturbances resulting in compressive stress concentration in the vertical direction and tensile stress in the incident direction.As the wavelength and rising time increased,there was a tendency for the amplitude of stress concentration to initially rise and then converge.Moreover,a series of 3D FEM models were established to evaluate the effect of different initial stress states on the dynamic failure of the tunnel surrounding rock.The results indicated that the failure of the surrounding rock was significantly influenced by the direction of the static maximum principal stress and the direction of the dynamic disturbance.Under the coupling of static and blasting loading,damage around the tunnel was more prone to occur in the dynamic and static stress concentration coincidence zone.Finally,the damage modes of rock tunnel under static stress and blasting disturbance from different directions were summarized and a proposed support system was presented.The results reveal the mechanisms of deep-buried rock tunnel destruction and dynamically triggered rockburst.
关键词
应力波散射/动态应力分析/岩质隧道/动态破坏分析Key words
stress wave scattering/dynamic stress analysis/rock tunnel/dynamic failure analysis引用本文复制引用
基金项目
National Natural Science Foundation of China(12072376)
Fundamental Research Funds for the Central Universities,China(10533220215858)
出版年
2024
NETL
NSTL
万方数据