摘要
GFRP筋树脂在湿热环境下较易于吸收水分,对GFRP筋的抗拉强度及耐久性能造成不可逆的损伤,然而,目前针对高温养护混凝土中GFRP筋的吸湿性能研究十分有限。因此,针对不同纤维含量比例、不同养护温度环境,研究了高温养护混凝土中GFRP筋吸湿行为的影响规律,建立了蒸养混凝土中GFRP筋扩散系数的预测模型。试验结果表明:GFRP筋复合材料的吸湿行为基本满足Fick第二定律;纤维含量与养护温度对GFRP筋的吸湿行均存在较大的影响;当纤维含量增加时,材料的平衡吸湿量、吸湿速率及扩散系数D均有所降低;当养护温度越高时,平衡吸湿量和扩散系数D越大,吸湿速率越高。但养护温度20℃时影响相对较小,当养护温度60℃以上时,吸湿行为影响较为明显。
The resin of GFRP bars is easy to absorb moisture in hot and humid environment,which causes irreversible damage to the tensile strength and durability of GFRP bars.However,the research on the moisture absorption performance of GFRP bars in high temperature curing concrete is very limited.Therefore,in view of the different fiber content ratios and the different curing temperatures,the influence of moisture absorption performance of GFRP bars in high temperature cured concrete was studied,and the prediction model of diffusion coefficient of GFRP bars in steam-curing concrete was established.The experimental results show that the moisture absorption behavior of GFRP bars basically meets the Fick’s Second Law;the moisture absorption behavior of GFRP bars is greatly affected by the fiber content and the curing temperature;the equilibrium moisture absorption,moisture absorption rate and diffusion coefficient D of the composites decrease with the fiber content increases;when the curing temperature increases,the equilibrium moisture absorption and diffusion coefficient D increase,and the moisture absorption rate increases.However,the effect of the curing temperature is relatively small at 20℃,and the effect on moisture absorption behavior is mainly reflected in the curing temperature above 60℃.
作者
杨文瑞
袁娇
冯中敏
黎惠莹
何雄君
Yang Wenrui;Yuan Jiao;Feng Zhongmin;Li Huiying;He Xiongjun(School of Architectural Engineering,East China University of Technology,Nanchang 330012,China;School of Transportation,Wuhan University of Technology,Wuhan 430063,China)
出处
《建筑结构》
CSCD
北大核心
2019年第22期97-100,96,共5页
Building Structure
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)
博士启动金(DHBK2017119)
国家自然科学基金(51178361)
关键词
GFRP筋
高温养护
纤维含量
吸湿率
扩散系数
GFRP bar
high temperature curing
fiber content ratio
moisture absorption rate
diffusion coefficient
