地震作用下岩体边坡锚固界面剪切作用数值模拟分析  

A numeral simulation of anchored interface shear stress for bolt in rock mass slope under earthquake

作　　者：龙哲[1] 言志信[1,2] 周小亮 LONG Zhe YAN ZhiXin ZHOU XiaoLiang(School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, 730000, China School of Civil and Traffic Engineering, Henan University of Urban Construction, Pingdingshan 467000, China)

机构地区：[1]兰州大学土木工程与力学学院,兰州730000 [2]河南城建学院土木与交通工程学院,平顶山467000

出　　处：《中国科学：技术科学》2017年第10期1049-1056,共8页Scientia Sinica(Technologica)

摘　　要：为研究地震作用下锚固岩体边坡中锚杆-砂浆界面和砂浆-岩体界面的剪切相互作用,揭示锚固界面上相互作用机理,同时获得地震作用下锚固岩体边坡两锚固界面的剪应力分布规律,采用有限差分软件FLAC3D建立锚固岩体边坡数值分析模型,并用interface接触面单元模拟锚杆-砂浆界面和砂浆-岩体界面的剪切相互作用,对简谐地震波作用下锚固边坡中全长黏结锚杆锚固界面剪应力的分布规律进行了研究,研究发现:在地震作用下,砂浆-岩体界面剪应力首先达到其极限黏结强度并出现脱黏现象,剪应力峰值从破坏面向锚杆两端发展;与此同时,锚杆-砂浆界面上的剪应力没有达到其极限黏结强度,但是该界面剪应力峰值会随着砂浆-岩体界面的脱黏而进行相应的调整;砂浆-岩体界面脱黏后,锚杆轴力呈两翼外凸的人字形曲线分布,轴力曲线拐点与界面剪应力曲线峰值点相对应,脱黏区域锚固体均匀拉伸,轴力分布均匀.该研究可为相关模型试验、现场监测、设计施工研究提供参考.In order to extract the distribution regularities of shear stress on both slope＇s anchored interfaces under earthquake at the same time,and reveal the mechanism of the shear interaction on anchored interfaces. Based on finite difference software FLAC3 D,we build an anchored rock slope numerical model,simulated shear interaction on cable-grout interface and grout-rock interface by interface element,to study the distribution regularities of wholly grouted anchor bar anchored interface shear stress in anchored slope under simple harmonic vibration of seismic waves. The results of the study include the following： the shear stress on grout-rock interface reaches ultimate bond strength first,and debonding,the peak value of shear stress on grout-rock interface develop from failure surface to bolt end; at the same time,the shear stress on bolt-grout interface doesn＇t reach ultimate bond strength,but the peak value of shear stress on bolt-grout interface move accordingly with that on grout-rock interface; after grout-rock interface debonding,the distribution of axial force along bolt is herringbone curve with both convex outer side,there is a one-to-one correspondence between curve inflection point of axial force and peak value point of shear stress on interface. The anchorage body in debonding region subjected uniform tension,the axial force in this region distributed relatively uniform. The study can provide references for study of model test,field monitoring,design and construction on relevant aspect.

关 键 词：锚固边坡 接触面单元 界面剪应力 锚杆-砂浆界面 砂浆-岩体界面 

分 类 号：P642.27[天文地球—工程地质学] TU476[天文地球—地质矿产勘探]