嵌岩抗浮锚杆承载性能现场试验与机理分析  

Field test and mechanism analysis of bearing capacity of rocksocketed anti-floating anchor

作　　者：闫楠[1,2] 孙淦 白晓宇 王忠胜[2] 刘一鸿 贾世祥 张亚妹 崔岚 YAN Nan;SUN Gan;BAI Xiaoyu;WANG Zhongsheng;LIU Yihong;JIA Shixiang;ZHANG Yamei;CUI Lan(School of Civil Engineering,Qingdao University of Technology,Qingdao 266520,China;Key Laboratory of Geological Safety of Coastal Urban Underground Space,Ministry of Natural Resources,Qingdao 266000,China;School of Science,Qingdao University of Technology,Qingdao 266520,China;Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China)

机构地区：[1]青岛理工大学土木工程学院,山东青岛266520 [2]自然资源部滨海城市地下空间地质安全重点实验室,山东青岛266000 [3]青岛理工大学理学院,山东青岛266520 [4]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《中南大学学报(自然科学版)》2025年第2期730-743,共14页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(52478348);山东省泰山学者项目(tsqn202306234);青岛市自然科学基金原创探索项目(24-4-4-zrjj-180-jch);山东省自然科学基金青年项目(ZR2023QE107)。

摘　　要：利用准分布式应变传感技术,测试抗浮锚杆在现场极限抗拔试验中杆体的应变变化,分析抗浮锚杆的内力分布特征及其荷载传递规律,揭示锚固长度对抗浮锚杆承载性能的影响机制,验证临界锚固长度的存在,并基于Hoek-Brown准则提出嵌岩抗浮锚杆临界锚固长度的有效计算公式。研究结果表明:抗浮锚杆杆体、灌浆体的荷载-位移曲线均存在拐点,分别在锚杆极限承载力的75%、60%处,拐点前位移呈线性变化,拐点后位移变化速率显著增大;随着荷载等级的增加,抗浮锚杆的荷载传递深度逐渐增大,锚杆杆体轴力呈相对慢速衰减的趋势,且轴力主要集中在浅部岩土层;杆-浆界面剪应力表现出先快速增加而后迅速减小的趋势,剪应力峰值出现在锚固深度约0.75m处;9根试验锚杆的极限抗拔承载力均为200kN左右,基于Hoek-Brown准则计算得到的临界锚固长度为2.78m,这均与现场试验结果基本吻合。研究结果可为嵌岩抗浮锚杆的设计提供参考。Using quasi-distributed strain sensing technology,the strain change of the anti-floating anchor was tested in the ultimate pull test in the field,the internal force distribution characteristics and load transfer rules of anti-floating anchor were analyzed,the influence mechanism of anchoring length on the bearing performance of anti-floating anchor was revealed,and the existence of critical anchorage length was verified.Based on Hoek-Brown criterion,an effective formula for calculating the critical anchorage length of rock-socketed anti-floating anchor was presented.The results show that there are inflection points in the load-displacement curves of the bolt body and the grout body,which are 75%and 60%of the ultimate bearing capacity of the bolt respectively.The displacement changes linearly before the inflection point,and the displacement change rate increases significantly after the inflection point.With the increase of the load level,the load transfer depth of the anti-floating bolt increases gradually,and the axial force of the bolt body decreases slowly,and the axial force mainly concentrates in the shallow rock layer.The shear stress at the rod-slurry interface increases rapidly at first and then decreases rapidly,and the peak shear stress occurs at the anchorage depth of about 0.75 m.The ultimate pulling capacity of the 9 test bolts is about 200 kN,and the critical anchorage length calculated based on the formula is 2.78 m,which is basically consistent with the field test results.The research results could provide reference for the design of rock-socketed anti-floating anchor.

关 键 词：抗浮锚杆 轴力 剪应力 锚固机制 临界锚固长度 现场极限抗拔试验 

分 类 号：TU473[建筑科学—结构工程]