海水环境下GFRP筋与低碱混凝土界面黏结性能研究  

Study on interfacial bonding behavior between GFRP reinforcement and low alkali concrete in seawater environment

作　　者：张宁 周健 李辉 徐名凤 陈智丰 刘成健 ZHANG Ning;ZHOU Jian;LI Hui;XU Mingfeng;CHEN Zhifeng;LIU Chengjian(School of Civil Engineering and Transportation,Hebei University of Technology,Tianjin 300401,China;Tangshan Polar Bear Building Materials Co.,Ltd.,Tangshan 063705,China)

机构地区：[1]河北工业大学土木与交通学院,天津300401 [2]唐山北极熊建材有限公司,河北唐山063705

出　　处：《混凝土》2024年第3期12-16,共5页Concrete

基　　金：国家自然科学基金(51878238);河北省自然科学基金(E2021202037);天津市交通运输科技发展项目计划(2021-32)。

摘　　要：针对GFRP筋在低碱耐腐蚀水泥基体环境下界面黏结性能的时变规律进行研究,采用中心拉拔试验方法测定了GFRP筋-矿渣硫铝酸盐水泥(G·SAC)混凝土、GFRP筋-硅酸盐水泥(OPC)混凝土在淡水和人工海水环境下养护30 d、90 d和180 d的界面黏结强度,并利用扫描电子显微镜(SEM)及pH计分析了孔溶液浸泡后GFRP筋微观结构的劣化过程及水泥基体孔溶液pH值的变化规律。结果表明:在淡水环境下,GFRP筋-G·SAC混凝土界面黏结强度随养护时间的增加而提高,但GFRP筋-OPC混凝土的黏结强度逐渐降低;在海水环境下,G·SAC基体碱度进一步降低,且海水对其强度发展有促进作用,GFRP筋-G·SAC混凝土在海水中的黏结强度较淡水增长较快。The time-varying law of interfacial bonding properties of GFRP bars in low alkali corrosion resistant cement matrix environment was studied.The interfacial bonding strengths of GFRP bars slag sulphoaluminate cement concrete and GFRP bars Portland cement concrete cured for 30 days,90 days and 180 days in fresh water and artificial seawater environment were measured by central pull-out test.The microstructure deterioration process of GFRP reinforcement and the change rule of pH value of cement matrix pore solution after soaking in pore solution were analyzed by scanning electron microscope(SEM)and pH.The results show that the interfacial bond strength of GFRP reinforcement slag sulphoaluminate cement concrete increases with the increase of curing time in fresh water environment,but the bond strength of GFRP reinforcement Portland cement concrete decreases gradually.In seawater environment,the basicity of slag sulphoaluminate cement matrix is further reduced,and seawater can promote the development of its strength.The bond strength of GFRP reinforcement slag sulphoaluminate cement concrete in seawater increases faster than that in fresh water.

关 键 词：矿渣硫铝酸盐水泥 玻璃纤维增强复合筋 黏结性能 低碱耐腐蚀 海水 

分 类 号：TU528.571[建筑科学—建筑技术科学]