摘要
为探究高地温对全长粘结式锚杆锚固的影响,借鉴前人推导所得全长粘结式锚杆应力分布的函数,引入锚固系统中材料参数的热变方程,建立全长粘结式锚杆弹性阶段含温度参数的力学模型。通过算例,总结出3种温度下(50℃、100℃、150℃)力学模型随温度变化的规律,并通过室内拉拔试验验证了温度对全长粘结式锚杆粘结性能的影响。结果表明:(1)温度升高,锚杆同一锚固点的轴力变大,轴力极大衰减段向内移动,峰值剪应力均减小,剪应力峰值点内移;(2)温度升高,模型1锚杆有效锚固长度从1.8 m扩大到2.8 m,峰值剪应力分别较50℃下降21%和34%,剪应力峰值点从0.44 m内移至0.79 m;(3)温度升高,全长粘结式锚杆峰值剪应力减小,锚杆荷载传递长度增加,传递效率降低。
In order to explore the influences of high ground temperature on the anchoring of fully bonded anchor bolts,this paper introduces a thermal variable equation related to material parameters of the anchoring system based on the previously derived stress distribution function of fully bonded anchor bolts,and establishes a temperature pa⁃rameters inclusive mechanical model of fully bonded anchor bolts at elastic stage.Through calculation examples,this paper summarizes the change laws of mechanical properties with three different temperatures(50℃,100℃ and 150℃).In addition,it verifies the influences of temperature on the bond performance of fully bonded anchor bolts by the indoor pull-out test.The results show that:(1)as the temperature increases,the axial force at the same an⁃choring point of the anchor bolt increases,the maximum attenuation section of the axial force moves inwards,the peak shear stress decreases,and the peak point of the shear stress moves inwards;(2)as the temperature increases,the effective anchoring length of the anchor bolt in model 1 increases from 1.8 m to 2.8 m,the peak shear stress de⁃creases by 21%and 34%respectively compared to that at 50℃,and the peak point of the shear stress moves in⁃wards from 0.44 m to 0.79 m;(3)as the temperature increases,the peak shear stress of the fully bonded anchor bolt decreases,the load transfer length of the anchor bolt increases,and the transfer efficiency is reduced.
作者
李福海
李瑞
吴昊南
高浩
汪波
张桂斌
陈思银
LI Fuhai;LI Rui;WU Haonan;GAO Hao;WANG Bo;ZHANG Guibin;CHEN Siyin(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031;Yantai Architectural Design and Research Co.,Ltd.,Yantai 264000;Shanghai Municipal Engineering Design and Research Institute(Group)Co.,Ltd.,Shanghai 200092)
出处
《现代隧道技术》
CSCD
北大核心
2021年第4期157-162,169,共7页
Modern Tunnelling Technology
基金
国家自然科学基金(51308471)
四川省中央引导地方科技发展专项(2020ZYD011).
关键词
高地温
全长粘结式锚杆
模型试验
荷载传递函数
剪应力
轴力
温度参数
High ground temperature
Fully bonded anchor bolt
Model test
Load transfer function
Shear stress
Axial force
Temperature parameter
