带UHPC接缝的桥面板力学性能试验研究  

Experimental Study on Mechanical Property of Bridge Deck with UHPC Joint

作　　者：曾明辉 尹炳森 陈刚[3] 胡志坚[3] ZENG Ming-hui;YIN Bing-sen;CHEN Gang;HU Zhi-jian(Jiangxi Provincial Transportation Investment Group Co.,Ltd.,Nanchang,Jiangxi 330000,China;China Construction Third Bureau Green Industry Investment Co.,Ltd.,Wuhan,Hubei 430056,China;School of Transportation and Logistics Engineering,Wuhan University of Technology,Wuhan,Hubei 430063,China)

机构地区：[1]江西省交通投资集团有限责任公司,江西南昌330000 [2]中建三局绿色产业投资有限公司,湖北武汉430056 [3]武汉理工大学交通物流学院,湖北武汉430063

出　　处：《公路交通科技》2024年第3期125-131,共7页Journal of Highway and Transportation Research and Development

基　　金：国家重点研发专项项目(2017YFC0806000);江西省交通运输厅科技项目(2021C0004)。

摘　　要：为掌握带UHPC接缝的桥面板受弯状态下的力学特点,进一步探究UHPC接缝的合理宽度及在接缝宽度相同情况下,不同接缝截面形式、钢筋搭接形式对带UHPC接缝的桥面板抗弯性能影响,设计制作了一块现浇整体板和3块不同湿接缝构造的UHPC预制桥面板,并分别进行四点弯曲试验评估接缝处抗弯性能,对荷载-跨中位移曲线、荷载-主裂缝宽度曲线、混凝土荷载-拉应变曲线、混凝土荷载-压应变曲线、荷载-受拉钢筋应变曲线、极限抗弯承载能力、裂缝发展状况展开相关研究。结果表明:由于UHPC优异的力学性能,4组试验板的荷载-跨中挠度曲线基本相近,带UHPC接缝的桥面板极限承载力优于整体板;接缝宽度、钢筋连接方式相同的情况下,漏斗形或楔形接缝截面形式不会影响预制桥面板的极限承载力,彼此刚度差异不大;在保证桥面板整体性和承载力的前提下,预制桥面板UHPC湿接缝可减小为15 cm宽;UHPC接缝连接的整体性良好,不会影响现浇接缝区段及连接界面的抗拉性能,带UHPC接缝的预制拼装桥面板的初始裂缝和主裂缝均位于普通混凝土区域,UHPC的高弹性模量使得接缝区域局部刚度提高,相较于接缝周围混凝土区域,接缝处的受压区混凝土压应变与受拉区钢筋的拉应变都较小,接缝区域未出现裂缝,UHPC湿接缝与混凝土预制板界面处的裂缝扩展速度缓慢。In order to master the mechanical characteristics of bridge deck with UHPC(ultra high performance concrete)joints under bending conditions,moreover,to investigate the proper width of UHPC joints and the effect of different joint cross-sections and reinforcement lap forms on the flexural performance of bridge deck slabs with UHPC joints,which have the same joint width,one cast-in-place slab and 3 prefabricated test slabs are designed and manufactured.Four-point bending tests are conducted to evaluate the flexural performance of the joints,and related study,such as load-mid-span displacement curve,loadmain crack width curve,concrete load-tension strain curve,concrete load-compression strain curve,loadstrain curve of tensile reinforcement,ultimate flexural capacity and crack propagation,are carried out.The result shows that(1)due to the excellent mechanical properties of UHPC,the load-mid-span deflection curves of the 4 groups of test panels are basically similar,and the ultimate load carrying capacity of the bridge deck with UHPC joints is better than that of the whole panel;(2)in the case of the same width of the joints and the same reinforcement connection,the funnel-shaped or wedge-shaped joints in the form of cross-section will not affect the ultimate load carrying capacity of the prefabricated decks,and the difference of the stiffness of each other is not large;(3)with the premise of guaranteeing the integrality of the decks and the load carrying capacity,the wet joints with UHPC can be reduced to 15 cm width;(4)with the premise of ensuring the integrity and load bearing capacity of bridge deck,the UHPC wet joint of precast bridge deck can be reduced to 15 cm width,the integrity of UHPC joint connection is good,which will not affect the tensile performance of the cast-in-place joint section and the connection interface.The initial cracks and main cracks of precast assembled bridge deck with UHPC joints are located in the ordinary concrete area,the high modulus of elasticity of UHPC makes the joint area locally

关 键 词：桥梁工程 UHPC湿接缝 四点弯曲试验 预制桥面板 接缝宽度 

分 类 号：U443.31[建筑科学—桥梁与隧道工程]