集簇式焊钉连接件抗剪承载力试验及计算方法  

Experimental Study and Calculation Method of Shear Capacity of Cluster Stud Connectors

作　　者：邓文琴 胡楷文 刘朵[2,3] 赵兴宝 查上 张建东 DENG Wen-qin;HU Kai-wen;LIU Duo;ZHAO Xing-bao;ZHA Shang;ZHANG Jian-dong(College of Civil Engineering,Nanjing Tech University,Nanjing 211816,Jiangsu,China;School of Civil and Transportation Engineering,Hohai University,Nanjing 210098,Jiangsu,China;Jiangsu Transportation Research Institute,Nanjing 211112,Jiangsu,China)

机构地区：[1]南京工业大学土木工程学院,江苏南京211816 [2]河海大学土木与交通学院,江苏南京210098 [3]苏交科集团股份有限公司,江苏南京211112

出　　处：《中国公路学报》2022年第10期194-204,共11页China Journal of Highway and Transport

基　　金：国家自然科学青年基金项目(51908282);国家自然科学基金项目(51778288);江苏省自然科学基金青年基金项目(BK20190681,BK20180151);江苏省高等学校自然科学研究面上项目(19KJB580002);江苏省交通运输厅科技与成果转化项目(2019Y19);江苏省第十六批“六大人才高峰”高层次人才项目(JZ-056)。

摘　　要：为了深入研究集簇式焊钉连接件的抗剪性能,结合装配式钢混组合桥梁焊钉连接件布置特征,以焊钉层间距和焊钉排数为变化参数,设计并完成了5组共10个焊钉连接件的静力推出试验,并建立了25组集簇式焊钉连接件精细化有限元模型,提出了同时考虑焊钉层间距和焊钉排数引起的群钉效应的单钉抗剪承载力折减系数计算公式。试验和分析结果表明:集簇式焊钉连接件受剪作用下由于各排焊钉之间剪力传递的不均匀性出现分批剪断现象,焊钉层间距较小时,各层焊钉之间混凝土破坏区域发生重叠,削弱了焊钉的抗剪承载力;与单钉连接件的荷载-滑移曲线特征不同,集簇式焊钉连接件持荷段较长,呈现出较好的延性,其破坏阶段呈阶梯状分布规律,验证了各排焊钉之间的承剪不均匀现象;单钉平均抗剪承载力随焊钉层间距增大而增大,随焊钉排数的增加而减小,当焊钉层间距超过8d时,可忽略其对抗剪承载力的影响;受预制桥面板预留剪力槽孔尺寸限制,装配式钢混组合桥梁常用的集簇式焊钉连接件层间距取值为4d~8d,排数取值为3r~7r;基于推出试验和有限元参数分析结果提出了同时计入焊钉层间距和焊钉排数的集簇式焊钉连接件抗剪折减系数实用计算公式,可为装配式钢混组合桥梁中集簇式焊钉连接件的设计计算提供理论依据。The shear performance of cluster stud connectors was investigated in this study. Based on the layout characteristics of stud connectors for prefabricated steel-concrete composite beam bridges, five groups of 10 static push-out specimens of stud connectors were subjected to tests, and 25 groups of refined finite element models of the clustered stud connector were established. The analyzed parameters included the stud layer spacing and the number of stud rows. An equation for calculating the reduction coefficient of the single-stud shear capacity was derived. The proposed equation reflected the effect of the group studs simultaneously caused by the stud layer spacing and the number of stud rows. The test and analysis results show that the clustered stud connectors are sheared in batches, owing to the uneven shear force transmission between the stud rows. If the spacing between the stud layers is small, the concrete failure area between the studs in each layer overlaps, weakening the shear capacity of the cluster stud connectors. In contrast to load-slip curve characteristics of the single-stud connector, load-slip curves of the cluster stud connectors have a more extended load-bearing section, indicating that the cluster stud connector specimens exhibit good ductility. The load-slip curve of the cluster stud connector shows a step-like distribution pattern at failure, demonstrating the unevenness of shear between the stud rows. The average shear capacity of a single stud increases with increasing the stud layer spacing and decreases with an increasing number of stud rows. When the stud layer spacing exceeds eight times the stud diameter, the effect of the stud layer spacing on the shear capacity of the stud may be ignored. The layer spacing between the cluster stud connectors typically used in fabricated steel-concrete composite beam bridges ranges from 4d to 8d, and the number of rows ranges from 3r to 7r. Based on the results of the push-out tests and finite element parameter analysis, a practical calculation for

关 键 词：桥梁工程 群钉效应 推出试验 集簇式焊钉连接件 抗剪承载力折减系数 

分 类 号：U443.37[建筑科学—桥梁与隧道工程]