蒸养GFRP筋混凝土板压缩薄膜效应研究  

Compressive film effect of steam-curing GFRP reinforced concrete slab

作　　者：杨文瑞 袁娇 梁炯丰 张恺 何雄君[3] YANG Wenrui;YUAN Jiao;LIANG Jiongfeng;ZHANG Kai;HE Xiongjun(School of Architectural Engineering,East China University of Technology,Nanchang 330012,China;Department of Road and Material,Jiangxi Transportation Institute,Nanchang 330200,China;School of Transportation,Wuhan University of Technology,Wuhan 430063,China)

机构地区：[1]东华理工大学建筑工程学院,江西南昌330012 [2]江西省交通科学研究院道路与材料中心,江西南昌330200 [3]武汉理工大学交通学院,湖北武汉430063

出　　处：《混凝土》2020年第11期112-116,共5页Concrete

基　　金：江西省自然科学基金(20181BAB216027);江西省教育厅科技计划项目(GJJ170486);江西省交通厅科技项目(2014Y0015);江西省交通厅科技项目(2017H0007);博士启动项目(DHBK2017119);国家自然科学基金(51178361)。

摘　　要：蒸养混凝土板在桥梁结构中广泛应用,GFRP筋的使用可提高蒸养混凝土板的耐久性。然而,现行规范设计未考虑GFRP筋混凝土板内的压缩薄膜效应(Compressive Membrane Action,CMA)而夸大了GFRP筋的负面影响,从而导致过高的配筋率,过高的造价,同时也未考虑钢筋相对不易变形的优势。因此,在考虑薄膜效应的基础上,针对蒸养养护过程中GFRP筋混凝土板的力学性能、GFRP筋与钢筋配筋配制方式展开研究。试验研究结果显示:GFRP筋与钢筋不同布置方式及蒸养混凝土板不同长宽比例,改变了蒸养混凝土板裂缝发展,极限荷载及挠度变形性能;钢筋作为分布筋固定GFRP筋受力筋时,可抑制了结构裂缝的开展,降低了混凝土板的挠度。板的长宽比对性能影响较大,长宽比越大,其变形越明显,同时极限荷载降低,相同配筋方式及相同受力筋面积的I号板与IV号板挠度值相差均达到80%以上。压缩薄膜效应分析同样验证了采用钢筋作为分布筋时,可在一定程度上提高GFRP筋的利用率;不同长宽比的混凝土板挠度变形相对较大,其薄膜效应更为明显。Steam-curing concrete slabs are widely used in bridge structures,and the use of GFRP bars can improve the durability of steam-curing concrete slabs.However,the current design code does not consider the Compressive Membrane Action-CMA effect in GFRP reinforced concrete slabs,which exaggerates the negative effect of GFRP reinforcement,resulting in excessive reinforcement ratio,making the completed GFRP reinforced concrete bridge deck structure more expensive,and does not take into account the relative advantage of the steel bar is not easy to deform.Therefore,on the basis of considering the film effect,the mechanical properties of GFRP reinforced concrete slabs during steam-curing and the allocation of GFRP bars and steel reinforcement are studied.The experimental results show that the different arrangement of GFRP bars and steel bars and the different length-width ratio of steam-curing concrete slabs change the crack development,ultimate load and deflection deformation performance of steam-curing concrete slabs.When steel bars are used as distributed bars to fix the stress bars of GFRP bars,the crack development of structures can be restrained and the deflection of concrete slabs can be reduced.The aspect ratio of the plate has a great influence on the performance.The larger the aspect ratio,the more obvious the deformation,and the ultimate load is reduced.The deflection value of plate I and plate IV with the same reinforcement pattern and the same area of reinforcement is more than 80%.Compression film effect analysis also verifies that the utilization of GFRP bars can be improved to a certain extent when steel bars are used as distributed bars.The deflection of concrete slabs with different aspect ratios is relatively large,and the film effect is more obvious.

关 键 词：蒸养 GFRP筋 混凝土板 配筋方式 压缩薄膜效应 

分 类 号：TU528.72[建筑科学—建筑技术科学]