矩形顶管隧道F型承插接头抗弯性能试验研究  

Experimental Study on Bending Performance of an F-Type Socket Joint in Rectangular Pipe-Jacking Tunnels

作　　者：许有俊 庞跃魁[1,2,3] 张朝 聂绪致 张旭[1,2,3] 刘天宇 XU Youjun;PANG Yuekui;ZHANG Chao;NIE Xuzhi;ZHANG Xu;LIU Tianyu(School of Civil Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China;Academician Workstation of Mine Safety and Underground Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China;Engineering Research Center of Urban Underground Engineering at Universities of Inner Mongolia Autonomous Region,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China)

机构地区：[1]内蒙古科技大学土木工程学院,内蒙古包头014010 [2]内蒙古科技大学矿山安全与地下工程院士专家工作站,内蒙古包头014010 [3]内蒙古科技大学内蒙古自治区高校“城市地下工程技术研究中心”,内蒙古包头014010

出　　处：《隧道建设（中英文）》2023年第7期1099-1108,共10页Tunnel Construction

基　　金：国家自然科学基金资助项目(51868062)。

摘　　要：为研究矩形顶管隧道在地基沉降及上部荷载变化等情况下F型承插接头的抗弯性能、变形规律及破坏特征,在管节底部布置不同数量的等效地基弹簧来模拟不同地质条件,开展不同地层条件下的接头弯曲试验。试验结果表明:1)加载初期,接头弯曲变形主要为钢套环变形,各等效地基下接头抗弯刚度差异较小。2)当位移加载至15~25 mm时,管节顶底板内侧与侧墙外侧出现裂缝,由于管节自身变形使得接头张开量随着加载位移的增大出现减缓,接头抗弯刚度曲线斜率增大,并以0.007 rad张开量为界线划分为2个阶段。3)根据拉线式位移计变化、接头混凝土应变及钢套环应变可知,顶底板中部及侧墙中部挠曲应力最大,且在上方荷载作用下,管节表现出被压扁的趋势。4)接头弯曲变形中,插口端混凝土会与承口端混凝土及钢套环发生挤压,顶板混凝土被压碎,钢套环由于挤压而发生翘曲。The bending mechanical performance,deformation mechanism,and failure characteristics of an F-type socket joint in a rectangular pipe-jacking tunnel are investigated under conditions of foundation settlement and variations in the upper load.Different numbers of equivalent foundation springs are arranged at the bottom of the pipe to simulate different geological conditions,and joint bending tests are conducted.The following results are obtained from the tests:(1)The bending deformation of the joint is mainly caused by deformation of the steel collar at the initial stage of loading.There is a small variation in the bending rigidity of the joint under different equivalent foundations.(2)When the loading displacement reaches 15~25 mm,cracks appear on the inside of the top and bottom plates as well as the on the outside of the sidewall.As the loading displacement increases,the change rate of the joint opening decreases and the slope of the bending rigidity curve for the joint increases because of the deformation of the pipe joint itself.There are two regimes in the bending rigidity,where the transition between these regimes occurs at a joint opening of 0.007 rad.(3)Based on the change in the reading on the wire displacement gauge,the highest strain occurs in the joint concrete and the steel collar and the highest flexural stress occurs in the middle of the roof and floor and the middle of the sidewall.The action of the upper load induces flattening deformation of the pipe section.(4)During the bending deformation of the joint,the socket concrete is squeezed along with the jack concrete and the steel collar,the roof of the socket concrete is crushed,and the steel collar warps because of concrete extrusion.

关 键 词：矩形顶管 F型承插接头 模型试验 弯曲刚度 受力性能 变形特征 

分 类 号：U45[建筑科学—桥梁与隧道工程]