平钢板-UHPC组合桥面板湿接缝抗正弯试验与接缝折减系数  

Experimental study on resistance to positive bending of wet joints in steel-UHPC composite bridge deck and joint reduction coefficient

作　　者：李传习[1,2] 韦积鋆 贺龙飞 Li Chuanxi;Wei Jijun;He Longfei(Changsha University of Technology,Changsha 410114,China;Xinjiang North Xin Road and Bridge Group Co.,Ltd.,Urnmqi 830057,China)

机构地区：[1]长沙理工大学,湖南长沙410114 [2]新疆北新路桥集团股份有限公司,新疆乌鲁木齐830057

出　　处：《土木工程学报》2025年第2期72-85,共14页China Civil Engineering Journal

基　　金：国家自然科学基金(52078059,51808055)。

摘　　要：针对平钢板-UHPC组合桥面板湿接缝抗正弯性能研究不足和能否取消平钢板-UHPC组合桥面板下层纵筋的问题,文章开展了单层纵筋的平钢板-UHPC组合桥面板(即取消下层纵筋)湿接缝正弯曲静力性能足尺模型试验,考察裂纹开展过程、破坏形态、荷载-跨中挠度曲线、荷载-最大裂缝宽度曲线等,并与双层纵筋平钢板-UHPC组合桥面板湿接缝破坏形态和相应曲线进行对比;在相关假定基础上,提出考虑接缝折减系数的平钢板-UHPC组合桥面板湿接缝弯矩-应变关系计算的分层总和法;编写基于文章假定和考虑接缝折减系数的分层总和法计算程序;对9片整体浇筑的平钢板-UHPC组合桥面板的特征弯矩进行计算,并与试验结果进行了对比;根据分层总和法程序计算值与试验值尽量接近或相等求得2种常见界面处理方式的接缝折减系数。结果表明:单层纵筋的平钢板-UHPC组合桥面板湿接缝正弯曲破坏模式为适筋梁破坏模式,相比双层纵筋的原设计,破坏模式、开裂荷载、屈服荷载、极限荷载、荷载-跨中挠度曲线、荷载-最大裂缝宽度曲线和荷载-相对滑移曲线基本不变;纤维连续性较弱的接缝对平钢板-UHPC组合桥面板湿接缝截面抗压部分能力的影响可忽略不计,对截面抗拉部分能力的影响可通过折减系数考虑,且铁丝网处理的接缝折减系数为0.4,人工凿毛处理的接缝折减系数为0.5。This article aims to address the research gap regarding the flexural behavior of wet joints in UHPC-steel plate composite bridge decking,exploring whether it is feasible to eliminate the lower layer of longitudinal reinforcement in UHPC-steel plate composite bridge decking.To this end,a full-scale model test was conducted to investigate the static flexural performance of single-layer longitudinal reinforcement UHPC-steel plate composite bridge decking,involving elimination of the lower layer of longitudinal reinforcement.The test focused on the examination of the crack development process,failure mode,load-span deflection curve,load-maximum crack width curve,and comparison of the failure mode and corresponding curves with those of double-layer longitudinal reinforcement UHPC-steel plate composite bridge decking.Based on the relevant assumptions,a layered summation method considering the joint reduction factor for calculation of the bending moment-strain relationship of wet joints in flat steel plate-UHPC composite deck slabs is proposed.Additionally,a computational program is developed based on the assumptions and the proposed layered total method.The characteristic moments of nine monolithically cast UHPC-steel plate composite bridge decking specimens are calculated and compared with the experimental results.The joint reduction coefficients for two common interface treatment methods are obtained by minimizing the differences between the calculated and experimental values.The results demonstrate that the flexural failure modes of single-layer longitudinal reinforcement UHPC-steel plate composite bridge decking wet joints are similar to that of joints with the double-layer longitudinal reinforcement original design.There are little changes in failure mode,cracking load,yield load,ultimate load,load-span deflection curve,load-maximum crack width curve,and load-relative slip curve.The influence of fiber discontinuity on the compressive strength of the wet joint region in the flat steel plate-UHPC composite bridge de

关 键 词：平钢板-UHPC组合桥面板 湿接缝 正弯曲性能 试验研究 分层总和法 接缝折减系数 

分 类 号：U441.4[建筑科学—桥梁与隧道工程]