隧道衬砌混凝土/岩石组合体动力学特性数值模拟研究  

Numerical Simulation of Dynamic Characteristics of Tunnel Lining Concrete/Rock Interface

作　　者：高欢 翟越[1,2] 汪铁楠 谢怡帆 李艳 GAO Huan;ZHAI Yue;WANG Tienan;XIE Yifan;LI Yan(School of Geology Engineering and Geomatics,Chang’an University,Xi’an 710054,China;Key Laboratory of Western China’s Mineral Resources and Geological Engineering(Ministry of Education),Chang’an University,Xi’an 710054,China)

机构地区：[1]长安大学地质工程与测绘学院,西安710054 [2]长安大学西部矿产资源与地质工程教育部重点实验室,西安710054

出　　处：《振动与冲击》2023年第11期107-114,138,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(41772277,41941019);陕西省自然科学基础研究项目(2020JQ-373)。

摘　　要：为探讨混凝土-花岗岩组合体的动态破坏机理,采用LS-DYNA软件建立分离式霍普金森压杆(split Hopkinson pressure bar,SHPB)数值模型,模拟了组合体在不同冲击荷载、主动围压、节理接触面积(JMC)、锯齿形状和界面倾角下的σ-ε关系、强度特性和能量特性。结果表明:组合体的抗压强度与围压、JMC和冲击压强呈正相关,随界面倾角α的增大(0°→90°)呈“U”形变化,倾角α接近材料破坏角45°时组合体破坏最严重,耗散能最大;界面的存在使得应力波在混凝土-岩石试件中传播更为复杂,组合体动态峰值抗压强度的大小主要取决于混凝土,具有明显的应变率、围压增强效应;同一入射能作用下,其值接近组合材料屈服极限时,混凝土-花岗岩、花岗岩-混凝土组合体和混凝土单体的反射能接近,相比混凝土单体,波阻抗大的岩单体透射能大,吸收能小;组合体破碎形态主要表现为混凝土的劈裂和压剪破坏。研究结果有助于理解组合岩层的动态破坏规律。In order to study the dynamic failure mechanism of concrete-rock combined body,the split Hopkinson pressure bar(SHPB)numerical model was established by LS-DYNA software.The relationship between curves ofσ-ε,the strength and energy characteristics of the combined body with different impact load,active confining pressure,joint contact area,shape and rock dip angle were analyzed.The results show that:among the above five factors,the interaction between rock dip angle and peak stress is the strongest,which satisfies the power function relationship.When the rock dip angle is close to the material failure angle of 45°,the combined body failure is more serious,and the dissipation energy is the largest;the existence of interface makes the propagation of stress wave in concrete rock specimen became more complex,and the dynamic peak strength of the combined body mainly depends on the concrete.Under the same incident energy,the reflection energy of concrete-granite,granite-concrete samples and concrete monomer is more closer.Compared with the concrete monomer,the transmission energy of rock monomer with high wave resistance is larger,and the absorption energy is smaller.The fracture morphology of composite is mainly manifested by splitting and compression shear failure of concrete.The research is helpful for understanding the dynamic failure law of rock strata.

关 键 词：岩石力学 混凝土 组合体 有限元模拟 分离式霍普金森压杆(SHPB) 动态压缩性能 

分 类 号：P642.4[天文地球—工程地质学] TU931[天文地球—地质矿产勘探]