摘要
为探明钢-超高性能混凝土(Ultra-HighPerformanceConcrete,UHPC)轻型组合桥面结构在施工中受行车扰动后的抗裂性能,以重庆鱼嘴长江大桥为背景,进行了理论和试验研究.首先通过有限元计算获得施工中行车引起的UHPC层顶面最大拉应变(以下简称扰动幅度),计算结果表明:该桥UHPC层在施工中受到的最大纵、横向扰动幅度分别为144με和60με;接下来,依照实桥结构,设计并制作6个模型试件;然后,将试件平均分为两组,每组设1个不受扰动的对照试件和2个在UHPC凝结过程中接受扰动的扰动试件,两组试件的设计扰动幅度分别为160με和240με;最后,通过四点负弯矩静力试验对比了对照试件和扰动试件的抗裂性能.试验结果表明:幅度不大于160με的扰动对试件的抗裂性能无明显影响;幅度大于160με的扰动对试件的UHPC层造成损伤,导致试件的名义开裂强度降低,因此,建议在实桥施工过程中将行车扰动幅度的限值取为160με.
In order to reveal the crack-resisting performance of the steel-Ultra-High Performance Concrete(UHPC)lightweight composite deck structure subjected to traffic disturbance during construction,theoretical and ex⁃perimental studies based on the Chongqing Yuzui Yangtze River Bridge are presented in this paper.Firstly,the maxi⁃mum tensile strain of the UHPC layer’s top surface caused by traffic during construction(referred to as disturbance amplitude hereinafter)was obtained through finite element analyses,and the results showed that:during construction,the maximum longitudinal and transverse disturbance amplitudes of the UHPC layer of this bridge were 144μεand 60με,respectively.Secondly,6 model specimens were designed and manufactured with reference to the actual struc⁃ture.Then,the specimens were divided into two groups,each group included one undisturbed control specimen and two disturbed specimens,which were subjected to simulated traffic disturbance during the setting of UHPC.The de⁃signed amplitudes of these two groups were 160μεand 240με,respectively.Finally,the crack-resistance perfor⁃mance of the control specimens and the disturbed specimens were compared through 4-point negative moment static tests.The experimental results showed that the disturbance did not substantially affect the crack-resisting perfor⁃mance of the specimens when its amplitude was less than 160με.On the contrary,the disturbance aroused damages to the UHPC layer when its amplitude was over 160με,resulting in a decrease in the nominal cracking stresses of the disturbed specimens.Therefore,it is suggested that the limit of traffic disturbance amplitude during construction should be set to 160με.
作者
邵旭东
莫然
曹君辉
陈玉宝
SHAO Xudong;MO Ran;CAO Junhui;CHEN Yubao(College of Civil Engineering,Hunan University,Changsha 410082,China;Hunan Provincial Laboratory for Wind and Bridge Engineering,Hunan University,Changsha 410082,China)
出处
《湖南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2022年第3期1-13,共13页
Journal of Hunan University:Natural Sciences
基金
国家重点研发计划资助项目(2018YFC0705406)
国家自然科学基金资助项目(52038003)
国家自然科学基金资助项目(51978259)。
关键词
桥梁工程
钢-UHPC轻型组合桥面结构
试验研究
模拟行车扰动
抗裂性能
UHPC损伤
bridge engineering
steel-UHPC lightweight composite deck structure
experimental study
simu⁃lated traffic disturbance
the crack-resisting performance
damage of UHPC
