摘要
为满足深埋排水盾构隧道在高内水压和高水土压力作用下的特殊工作要求,需要采用高刚性的接头连接形式对盾构隧道管片进行可靠连接。拟采用一种在手孔内部全面包钢的"口字型"铸铁件及与之连接的锚筋作为接头预埋件结构体系,以满足接头的刚度要求。由于接头的特殊形式,对于其力学性能尚缺乏充足的研究。文章对其展开了接头力学试验,分析了该接头结构形式的变形特性、承载力以及破坏模式。研究结果表明,管片接头承载力满足各设计工况荷载要求,当轴力为0时,极限抗弯承载力为1 494 kN·m。管片接头转角受所受弯矩和轴力控制,当轴力一定时,转角随着弯矩的增大而增大;而当弯矩一定时,转角随着轴力的增大而减小。在接头弯矩增加且轴力保持为0时,接头挠度、转角、螺栓应力、锚筋应力均呈现明显的双线性特征,当接头弯矩小于1 144 kN·m时,接头刚度较小;当弯矩大于1 144 kN·m时,接头刚度增大。由此可以得出当接头所受轴力为0时,接头弯矩值达到1 144 kN·m后嵌缝混凝土接触。各设计工况下中手孔周围裂缝发展情况较轻微,最大裂缝宽度不大于0.2 mm,满足深埋排水隧道的使用要求。接头的破坏是由螺栓的屈服引起的,螺栓受拉屈服后,接头截面受压区迅速减小,嵌缝混凝土接触造成接缝上表面混凝土压碎、剥落。
In order to meet the need of special working requirements of deep-buried drainage shield tunnel which suffers from high inner water pressure and high water-earth pressure,high-stiffness segment joints are needed to connect segments effectively.For the requirement of joints stiffness,a type of mouth shaped iron casting which covers the all faces of hand hole as well as the anchor bars connected to it is adopted as the embedded parts of joints.Because of the specificity of the joints form,the mechanical properties of joints are lack of research.This article conducts mechanical tests for the joints and analyzes the deformation properties,the bearing capacity and the failure modes.The test results show that:the bearing capacity of the segment joints meets the requirements of each design condition.The ultimate bearing capacity of the joints is 1 494 kN·m in the condition of axial force 0.The joint rotational angle is controlled by bending moment and axial force.When the axial force is constant,the rotation angle increases as the bending moment increases;on the other hand,the rotation angle decreases with the increase of the axial force when the moment is constant.When the joint bending moment increases and the axial force remains at 0,the joint deflection,rotational angle,bolt stress and anchor bar stress all show obvious bilinear characteristics.When the joint bending moment is less than 1 144 kN·m,the joint stiffness is relatively small;however,when the bending moment is greater than 1 144 kN·m,the joint stiffness increases.It can be concluded that when the axial force of the joint is 0,the reserved seam closes up after the joint moment value reaches 1 144 kN·m.Because the development of cracks around the hand hole is relatively slight and the maximum crack width is not more than 0.2 mm under each design condition,the use requirements for deep-buried drainage tunnels are met.The damage of the joint is caused by the yield of the bolts.After the bolts yield,the compression area of the joint section is rapidly redu
作者
金瑞
朱合华
周龙
闫治国
沈奕
官林星
温竹茵
李耀良
JIN Rui;ZHU Hehua;ZHOU Long;YAN Zhiguo;SHEN Yi;GUAN Linxing;WEN Zhuyin;LI Yaoliang(Department of Geotechnical Engineering,Tongji University,Shanghai 200092;State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092;Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University,Shanghai 200092;Shanghai Municipal Engineering Design Institute( Group) Co. ,Ltd. ,Shanghai 200092;Shanghai Foundation Engineering Group Co. ,Ltd. , Shanghai 200002)
出处
《现代隧道技术》
EI
CSCD
北大核心
2018年第A02期561-572,共12页
Modern Tunnelling Technology
基金
上海市科学技术委员会科研计划项目(16DZ1202200).
关键词
盾构隧道
高刚性管片接头
高内水压
力学试验
Shield tunnel
High-stiffness segment joint
High inner water pressure
Mechanical test
