全长黏结式锚杆锚固段荷载传递机制非线性分析  

NONLINEAR ANALYSIS ON LOAD TRANSFER MECHANISM OF WHOLLY GROUTED ANCHOR ROD ALONG ANCHORING SECTION

作　　者：黄明华[1] 周智[2] 欧进萍[1,2] 

机构地区：[1]哈尔滨工业大学土木工程学院,黑龙江哈尔滨150090 [2]大连理工大学土木工程学院,辽宁大连116024

出　　处：《岩石力学与工程学报》2014年第A02期3992-3997,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金："十二五"国家科技支撑计划项目(2011BAK02B01);国家自然科学基金面上项目(50978079)

摘　　要：从锚杆拉拔试验的荷载位移曲线出发,建立锚固界面的非线性剪切滑移模型以及锚杆锚固段荷载传递的非线性微分方程,获得锚杆锚固段的轴力和界面剪应力解析解,对非线性剪切滑移模型曲线特征以及锚杆锚固段的轴力和界面剪应力分布与传递特征进行分析。结果表明:建立的非线性剪切滑移模型曲线具有剪应力峰值点,随着剪切位移的增加,界面剪应力呈现先上升再下降的变化趋势,即该模型合理地考虑锚固界面的软化特征。拉拔荷载作用下,锚杆锚固界面经历弹性黏结阶段、弹塑性变形阶段以及快速软化阶段3个阶段,界面剪应力分布逐渐从单调递减曲线演变为单峰曲线,且界面剪应力作用范围随着拉拔荷载的增大而逐渐向锚杆远端扩展,以致极限状态下整个锚固界面发生软化而失效破坏。建立的轴力和界面剪应力解析解简单实用,适用于分析整个张拉过程中锚杆锚固段的荷载传递特征,为全长黏结式锚杆锚固段荷载传递机制研究提供理论参考。A novel nonlinear shear-slipping model of anchor rod according to load-displacement curve in the pullout test was established. Based on this model,the nonlinear differential equation of load transfer was established and the analytical solutions of axial force and shear stress were developed. The features of this model as well as the axial force and shear stress distributions along the anchor rod were analyzed. Results indicate that this model gives a peak value in its curve. With the slip increases,the shear stress initially goes up to the peak value then decreases,that is,this model characterizes the softening behaviors of anchorage interface reasonably. Under the pulling load,the anchorage interface undergoes three stages including elastic bonding stage,elastic-plastic deformation stage and rapidly softening stage. With the increase of pulling load,the shear stress distribution evolves from a monotone decay curve into a single peak curve and the influencing zone of the shear stress expands into far end gradually. Under the ultimate limited state,the whole anchorage interface softens rapidly into failure. The developed solutions are suitable for analyzing axial force and shear stress along anchor rod undergoing various stages,which provides theoretical reference for researches on the load transfer mechanism of wholly grouted anchor rod.

关 键 词：岩土工程 全长黏结式锚杆 剪切滑移模型 荷载传递机制 非线性分析 

分 类 号：TU472[建筑科学—结构工程]