钢-UHPC组合板环氧黏结界面抗剪与抗拉性能试验  

Shear and tensile performance tests of epoxy bonding interface between steel and UHPC slab

作　　者：李聪 陈宝春[2,3] 谢泽豪[4] 苏家战 Li Cong;Chen Baochun;Xie Zehao;Su Jiazhan(Guangxi University,Nanning 530004,China;Fuzhou University,Fuzhou 350108,China;National Center for Joint International Research of Bridges Technology Innovation and Risk Mitigation,Fuzhou 350108,China;Fu Jian Communications Planning&Design Institute Co,Ltd,Fuzhou 350000,China)

机构地区：[1]广西大学,广西南宁530004 [2]福州大学,福建福州350108 [3]桥梁技术创新与风险防治国家级国际联合研究中心,福建福州350108 [4]福建省交通规划设计院有限公司,福建福州35000

出　　处：《土木工程学报》2023年第1期25-36,56,共13页China Civil Engineering Journal

基　　金：国家重点研发计划(2018YFC0705400);广西大学高层次人才资助项目(A3030051017,A3030051026);广西创新驱动重大专项(AA18118055)。

摘　　要：文章以预制UHPC板与钢板采用环氧树脂黏结剂连接的组合结构为对象,开展了连接界面抗剪与抗拉的试验研究。试验结果表明,试件中的环氧树脂黏结剂和UHPC材料本身均保持完好;破坏位置,抗剪试件为黏结剂与钢板交界面,抗拉试件为黏结剂与UHPC的交接面;破坏性质为脆性,交接面出现滑移或分离后快速丧失承载力。抗剪强度受黏结面积影响不大,实测值平均值2.59MPa,抗剪强度设计值为1.36MPa。抗拉强度与黏结面积有关,当试件尺寸由160mm增大至200mm,实测值分别为2.74MPa和1.86MPa,降幅超过30%,抗拉强度设计值为0.78MPa。UHPC中钢纤维掺量在1%~2%范围内对抗拉黏结强度影响可忽略。建立了钢-UHPC组合板有限元模型进行受力分析。分析表明,在轮载作用下,黏结层以受剪为主,沿横桥向最为不利;最不利荷载工况的最大剪应力和竖向拉应力分别1.11MPa和0.15MPa,均低于黏结剂抗剪和抗拉强度设计值。根据试验和实例分析结果,考虑到黏结剂连接脆性破坏特性,建议重视胶结界面的处理,重点关注抗剪强度问题。In this work, the shear and tensile tests of bonding interface were carried out for the epoxy resin bonded steel-precast UHPC slab composite structures.The test results showed that the epoxy resin adhesive and the UHPC material themselves in the composite specimen remain intact.The failure location of the specimens under shearing is at the bonding interface between the steel plate and the adhesive, while for the tensile specimens the failure location is at the bonding interface between UHPC slab and adhesive.Both of the failure modes are brittle, characterized by rapid loss of the bearing capacity of specimens due to the slippage or separation of bonding interface.The shear strength may not be greatly affected by the bond area, and the measured average value and design value of shear strength are 2.59MPa and 1.36MPa, respectively.The tensile strength is related to the bond area.When the size of tensile specimen is increased from 160mm to 200mm, the measured tensile strength decreases from 2.74MPa to 1.86MPa with a decrease rate of 30%, and the design value of tensile strength is 0.78MPa.In addition, the steel fiber volume content of 1~2% in UHPC has little effect on the tensile strength.Furthermore, a finite element model of steel-UHPC composite slab was established and analyzed.The analysis results showed that under vehicle loads the bonding layer is mainly subjected to the shear force, and it shall be most unfavorable in the transverse direction of bridge.The maximum transverse shear stress and vertical tensile stress in the most unfavorable load conditions are 1.11MPa and 0.15MPa, which are lower than the design value of shear strength and that of tensile strength of epoxy resin adhesive respectively.Based on the test and analysis results and in view of the brittle failure characteristics of binder, it is recommended that the emphasis shall be put on the treatment of bonding interfaces and particular emphasis on the shear strength issue.

关 键 词：预制UHPC板 环氧黏结剂 抗剪 抗拉 黏结强度 黏结面积 有限元分析 

分 类 号：U443.32[建筑科学—桥梁与隧道工程]