预制装配墩柱-桩基础承插节点冲切性能研究  

Study on Punching Shear Performance of Socket Node of Precast Pier-Pile Foundation

作　　者：谢濠君 张广达 韩强[1] 杜修力[1] Xie Haojun;Zhang Guangda;Han Qiang;Du Xiuli(State Key Laboratory of Bridge Engineering Safety and Resilience,Beijing Uniwversity of Technology,Beijing 100124,China;College of Civil Engineering,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]北京工业大学桥梁工程安全与韧性全国重点实验室,北京100124 [2]福州大学土木工程学院,福建福州350108

出　　处：《市政技术》2024年第10期106-118,共13页Journal of Municipal Technology

基　　金：国家自然科学基金项目(52338010,52208451)。

摘　　要：承插连接由于具有整体性能好、施工工序简单和拼装容许误差大等优点,成为预制装配桥墩节点的有效连接方式之一。为探明桩基础承插节点的冲切失效模式及承载力计算方法,采用ABAQUS有限元软件建立预制装配墩柱-桩基础承插节点数值计算模型,通过UHPC-NC直剪试验和墩柱-桩基础轴压试验进行了数值模型校验,研究了底板、接缝和承插连接参数对预制装配墩柱-桩基础承插节点的冲切传力机制、承载能力和失效模式的影响规律,提出了预制装配墩柱-桩基础承插节点冲切承载力计算公式。数值模拟结果表明,预制装配墩柱-桩基础承插节点的传力路径沿墩柱底部到桩的顶部;峰值荷载过后,承台底部混凝土开裂失效;接缝承载力和UHPC与混凝土之间的接触面积呈正相关,承台的冲切承载力与底板高度呈正相关。此外,当承插深度与底板高度之比由0.60增大到2.08时,接缝承载力提升了80.2%,而承插连接以及底板承载力分别降低了27.7%、52.9%,承插连接参数与底板参数具有相同的变化趋势,且底板承载力对承插连接承载力的占比较大,说明底板对承插节点承载力的贡献起主导作用。通过对已有试验和数值模拟分析,将底板和接缝的贡献系数分别取为1.00和0.92,为类似预制装配墩柱-桩基础承插节点冲切承载力的计算提供了依据。Because of good overall performance,simple construction process and large assembling errors,socket connection has become one of the effective connection methods for prefabricated bridge pier connections.In order to investigate the punching shear failure mode and bearing capacity calculation method of socket connection of pile foundation,the calculation model of the joint was established by the ABAQUS finite element software.The numerical model was verified by the straight shear test of UHPC-NC and the axial compression test of pier-pile caps.The influence law of base plate,grouting joints,socket connection parameters on the punching shear strength transmission mechanism,bearing capacity and failure modes were investigated.And the calculation formula was proposed.Numerical simulation results showed that the force transmission path of the precast pier-pile caps with socket connection is from the bottom of the column to the top of the pile;After the peak load,the concrete at the bottom of the cap cracked and failed;The joint bearing capacity is positively correlated with the contact area between the UHPC and the concrete,and the punching bearing capacity of the cap is positively correlated with the thickness of the base plate.In addition,when the ratio of socket depth to base plate height increased from 0.6 to 2.08,the bearing capacity of the joint increased by 80.2%,while the bearing capacity of the socket connection and the base plate decreased by 27.7% and 52.9%,respectively.The socket connection parameters had the same trend with the base plate parameters.The base plate bearing capacity accounted for a larger portion of the bearing capacity of the socket connection,which indicated that the base plate played a dominant role in the contribution to the bearing capacity of the socket node.By analyzing the existing tests and numerical simulations,the contribution coefficients of the base plate and the joint were taken as 1.00 and 0.92 respectively,which provides a basis for the calculation of punching shear bearing c

关 键 词：墩柱-桩基础 承插节点 冲切性能 界面黏聚力 荷载传递路径 承载力分配关系 

分 类 号：U443.25[建筑科学—桥梁与隧道工程]