氯盐侵蚀作用后钢-BFRP复合筋混凝土梁受弯性能  

Flexural behavior of concrete beams reinforced with steel-BFRP composite bars subjected to chloride corrosion

作　　者：葛文杰[1,2] 张素康 张志文 ASHRAF Ashour GUAN Zhongwei 孙传智 曹大富 GE Wenjie;ZHANG Sukang;ZHANG Zhiwen;ASHRAF Ashour;GUAN Zhongwei;SUN Chuanzhi;CAO Dafu(College of Civil Science and Engineering,Yangzhou University,Yangzhou 225127,China;Jiangsu Province Engineering Research Center of Prefabricated Building and Intelligent Construction,Suqian 223800,China;School of Engineering,University of Bradford,Bradford BD71DP,UK;School of Engineering,University of Liverpool,Liverpool L693GQ,UK)

机构地区：[1]扬州大学建筑科学与工程学院,江苏扬州225127 [2]江苏省装配式建筑与智能建造工程研究中心,江苏宿迁223800 [3]School of Engineering,University of Bradford,Bradford BD71DP [4]School of Engineering,University of Liverpool,Liverpool L693GQ

出　　处：《建筑结构学报》2023年第8期170-184,共15页Journal of Building Structures

基　　金：科技部国家外国专家项目(G2022014054L);国家自然科学基金项目(51678514);江苏省自然科学基金项目(BK20201436);扬州市市校合作专项(YZ2022194)。

摘　　要：为研究氯盐侵蚀对钢-玄武岩纤维复合筋(steel-basalt FRP composite bar,B-SFCB)混凝土梁受弯性能的影响,对经氯化钠溶液侵蚀作用后4种不同筋材(钢筋、BFRP筋和2种不同B-SFCBs)受拉性能和5组混凝土梁(钢筋和BFRP筋混凝土梁各1组、B-SFCB混凝土梁3组)受弯性能进行试验研究。分析应力水平和侵蚀时间对B-SFCB受拉性能及B-SFCB混凝土梁受弯承载力、变形、裂缝和破坏形态的影响。结果表明:各筋材抗拉强度随侵蚀时间增加而逐渐下降,无应力侵蚀180 d后,钢筋、B-SFCB和BFRP筋抗拉强度最大分别下降了12%、10%和4%;应力与氯盐侵蚀耦合作用后B-SFCB与BFRP筋的抗拉强度保留率低于无应力侵蚀筋材的;B-SFCB屈服后,混凝土梁仍具有稳定的抗弯刚度,其屈服荷载随筋材截面含钢率的提高而增大;侵蚀时间对无应力侵蚀混凝土梁荷载-挠度曲线影响较小,但对应力与侵蚀耦合作用梁荷载-挠度曲线影响较大,且随侵蚀时间增加而明显;荷载-裂缝宽度曲线变化趋势与荷载-挠度曲线基本一致。基于简化的材料本构模型和基本假定,定义了B-SFCB混凝土梁正截面受弯3种破坏形态并给出了其判别方法,建立了承载力简化计算式。借鉴美国ACI 440和中国GB 50010—2010规范,建立了B-SFCB混凝土梁刚度和裂缝宽度计算式,承载力、变形和裂缝宽度计算值与实测值吻合良好,可供工程设计参考。The tensile tests of four kinds of reinforcements(one steel bar,one basalt fibre-reinforced polymer(BFRP)bar,and two steel-basalt FRP composite bars(B-SFCBs))and flexural tests of five reinforced concrete beams(one reinforced with steel,one with BFRP steel and three with B-SFCBs)subjected to corrosion of sodium chloride solution were conducted to study the effects of chloride corrosion on the flexural behavior of concrete beams reinforced with B-SFCBs.The effects of stress level and corrosion duration on tensile properties of B-SFCBs as well as bearing capacity,deflection,crack,and failure patterns of concrete beams were investigated.The test results show that the strength retention ratio of bars decreases with the increase of corrosion duration,and the tensile strengths of steel bars,B-SFCB,and BFRP bars decrease by 12%,10%,and 4%,respectively,after 180 days of chloride corrosion.The strength retention ratios of stressed corroded B-SFCBs and BFRP bars are higher than those of corresponding unstressed corroded ones.The B-SFCBs reinforced concrete beams exhibit stable flexural stiffness after the yielding of B-SFCBs,and its yield load increases with the increase of the area ratio of inner steel to B-SFCB.For unstressed corroded beams,the effect of corrosion duration on the moment-deflection curve is limited.However,for stressed corroded beams,the influence gradually becomes obvious with the increase of corrosion duration.The variation trend of the moment-crack width curve is almost the same as that of the moment-deflection curve.Based on the simplified material constitutive models and reasonable basic assumptions,three failure modes and their discriminate formulas as well as formulae for flexural capacity were proposed.Based on the design code of ACI 440 and GB 50010—2010,the formulae for stiffness and crack width of B-SFCBs reinforced concrete beams were also developed.The predicted results of bearing capacity,deflection,and crack width are in good accordance with tested results,illustrating the validity of the

关 键 词：混凝土梁 氯盐侵蚀 钢-玄武岩纤维复合筋 承载力 挠度 裂缝 

分 类 号：TU375.1[建筑科学—结构工程] TU317.1