离层作用下全长粘结预应力锚杆受力特性分析  

Analysis on mechanical characteristic of full-length bonded prestressed bolt under separation layer

作　　者：尚福鲁 卢泽霖 朱珍[1] 王旭春[1] 张瑾 SHANG Fulu;LU Zelin;ZHU Zhen;WANG Xuchun;ZHANG Jin(School of Civil Engineering,Qingdao University of Technology,Qingdao 266520,China)

机构地区：[1]青岛理工大学土木工程学院,青岛266520

出　　处：《建筑结构》2025年第3期125-130,94,共7页Building Structure

基　　金：国家重点研发计划项目(2018YFC1505302);山东省自然科学基金面上项目(ZR2021MD005)。

摘　　要：为明确离层对全长粘结预应力锚杆的影响,建立了全长粘结预应力锚杆的力学模型,给出了离层作用下轴力和锚固界面剪应力的表达式。利用FLAC3D建立数值模型,分析了预紧力、离层两个因素对锚杆受力特性的影响规律。结果表明:不论有无离层变形,锚杆在不同预紧力作用下,轴力和锚固界面剪应力均呈现相同的变化规律;在裂隙张开处锚杆轴力、锚固界面剪应力均出现峰值;随着裂隙张开度增大,裂隙处开始脱锚,出现“轴力平台”和剪应力零值区间;裂隙张开度达到一定数值后,锚杆滑移破坏;裂隙位置对全长粘结预应力锚杆影响较大,按照敏感程度排序为:中裂隙<左裂隙<右裂隙。在实际工程中应当根据岩层性状合理设计锚杆长度,让一次粘结段尽可能远离可能发生离层变形的位置。In order to clarify the influence of the separation layer on the full-length bonded prestressed bolt,the mechanical model of the full-length bonded prestressed bolt was established,and the expressions of the axial force and the anchorage interface shear stress under the separation layer were given.FLAC3D was used to establish a numerical model to analyze the influence of preloading forces and layer separation on the mechanical characteristics of the bolt.The results show that with or without separation layer deformation,the axial force and anchorage interface shear stress of the bolt show the same change law under different preloading forces.The peak values of axial force and anchorage interfacial shear stress appear at the crack opening.With the increase of crack opening,the fracture begins to unanchor,and the“axial force plateau”and zero value interval of shear stress appear.When the crack opening reaches a certain value,the bolt slips and fails.The location of the crack has a great influence on the full-length bonded prestressed bolt,and the sensitivity ranking is as follows:medium crack<left fissure<right crack.In practical engineering,the length of bolt should be reasonably designed according to the characteristics of rock strata to make the primary bond section as far away as possible from the position where the separation layer deformation may occur.

关 键 词：预应力锚杆 全长粘结锚杆 离层 裂隙张开度 力学特性 

分 类 号：TD353[矿业工程—矿井建设] TU394[建筑科学—结构工程]