围堰封底混凝土与钢护筒界面粘结应力分布  

Distribution of Interfacial Bond Stress Between Based-sealing Concrete of Steel-box Cofferdam and Steel Casing

作　　者：曾健[1,2] 肖尧 黄修平 陈小龙[1,2] 顾程磊 ZENG Jian;XIAO Yao;HUANG Xiuping;CHEN Xiaolong;GU Chenglei(CCCC Second Harbor Engineering Co Ltd,Wuhan 430040,China;CCCC Wuhan Harbor Engineering Design and Research Co Ltd,Wuhan 430040,China;CCCC Second Harbor Consultants Co Ltd,Wuhan 430061,China)

机构地区：[1]中交第二航务工程局有限公司,湖北武汉430040 [2]中交武汉港湾工程设计研究院有限公司,湖北武汉430040 [3]中交第二航务工程勘察设计院有限公司,湖北武汉430061

出　　处：《土木工程与管理学报》2021年第4期110-114,共5页Journal of Civil Engineering and Management

基　　金：中交第二航务工程局有限公司科技研发项目(201907A)。

摘　　要：围堰作为临时设施为承台施工提供了无水环境。其中封底混凝土与钢护筒的可靠粘结是确保围堰安全和不渗水的关键。为研究封底混凝土与钢护筒界面的粘结应力分布规律,基于试验研究测试和既有研究成果,详细分析了封底混凝土与钢护筒界面粘结滑移本构关系,进而推导出二者界面粘结应力分布规律;采用三向非线性弹簧单元模拟封底混凝土与钢护筒界面的法向和两个切向作用,并基于二者的拉拔试验,细致分析了界面粘结应力。数值分析和试验场测试均表明,钢护筒与封底混凝土界面的粘结应力从加载端开始呈线性增大,并在距加载端10 cm左右处达到峰值,之后以指数形式降低;同时,界面粘结应力与相对滑移的二阶导数呈线性关系,并受制于钢护筒与封底混凝土的几何及材料参数。As a temporary facility,the cofferdam provides a water-free environment for the construction of the platform.The reliable bonding between the based-sealing concrete and the steel casing is the key to ensure the safety and impermeability of the cofferdam.In order to study the bond stress distribution law of the interface between the based-sealing concrete and the steel casing,based on experimental research and existing research results,the constitutive relationship of the bond slip between the based-sealing concrete and the steel casing is analyzed in detail,and then the bond stress distribution law of the interface is deduced.A three-dimensional nonlinear spring element is used to simulate the normal and two tangential effects of the interface between the based-sealing concrete and the steel casing,and the interface bond stress is analyzed in detail based on the pull-out test of both.Both numerical analysis and field test show that the bond stress of the interface between the based-sealing concrete and the steel casing increases linearly from the loading end,reaches the peak at about 10 cm away from the loading end,and then decreases exponentially.At the same time,there is a linear relationship between the interfacial bond stress and the second derivative of the relative slip and it is subject to the geometric and material parameters of the steel casing and the based-sealing concrete.

关 键 词：桥梁施工 钢护筒 封底混凝土 粘结力 界面滑移 

分 类 号：U445.556[建筑科学—桥梁与隧道工程]