海水海砂混凝土中混杂碳-玄武岩纤维筋拉伸性能退化机制及寿命预测
Degradation mechanism of tensile properties and life prediction of hybrid carbon/basalt fiber reinforced polymer bars in seawater sea-sand concrete
许艾沿 1杜运兴 1潘柳景泰 2朱德举3
作者信息
- 1. 湖南大学 土木工程学院,长沙 410082
- 2. 中南大学 土木工程学院,长沙 410083
- 3. 湖南大学 土木工程学院,长沙 410082;湖南大学 绿色先进土木工程材料及应用技术湖南省重点实验室,长沙 410082
- 折叠
摘要
为了研究海水浸泡下海水海砂混凝土(SSC)中以环氧树脂为基体的混杂碳-玄武岩纤维复材筋(CF-BF/Epoxy)拉伸性能退化规律,在不同温度(25℃、40℃和 55℃)下对SSC中的CF-BF/Epoxy进行海水浸泡,周期为 60天、90天和 120天,通过拉伸试验对CF-BF/Epoxy在SSC中的拉伸性能进行了研究,并利用SEM和FTIR对其微观结构的变化进行了分析.结果显示:环境温度对CF-BF/Epoxy的拉伸性能有明显影响,在55℃下浸泡120天后,抗拉强度下降了13.84%,弹性模量在3%范围内轻微波动,CF-BF/Epoxy出现伪延性;玄武岩纤维和碳纤维混杂延缓了SSC中OH-进一步向CF-BF/Epoxy内部侵蚀,而外层玄武岩纤维区域的树脂水解和树脂-纤维界面退化是CF-BF/Epoxy拉伸性能退化的主要原因.最后基于Arrhenius方程预测,嵌入SSC中的CF-BF/Epoxy的抗拉强度保持率将在584～803天内降至70%.
Abstract
To investigate the degradation pattern of tensile properties of epoxy resin-based hybrid carbon-basalt fiber reinforcing bars(CF-BF/Epoxy)in seawater sea-sand concrete(SSC)under seawater immersion,the CF-BF/Epoxy in SSC were soaked in seawater at different temperatures(25℃,40℃,and 55℃)for durations of 60,90 and 120 days.The tensile performance of the CF-BF/Epoxy in SSC was examined through tensile tests,and the changes in their microstructure were analyzed by SEM and FTIR.The results indicate that ambient temperature significantly affects the tensile properties of CF-BF/Epoxy.After 120 days of immersion at 55℃,the tensile strength decreases by 13.84%,the elastic modulus experiences a slight fluctuation within a 3%range,and pseudo-ductility is observed in the CF-BF/Epoxy.Additionally,blending of basalt fibers and carbon fibers delay the further intrusion of OH-from SSC into CF-BF/Epoxy,while the hydrolysis of the resin in the outer basalt fiber region and the degrada-tion of the resin-fiber interface are identified as the primary causes of the decline in the tensile properties of CF-BF/Epoxy.Lastly,based on the Arrhenius equation,it is predicted that the tensile strength retention rate of CF-BF/Epoxy embedded in SSC will drop to 70%between 584 and 803 days.
关键词
混杂碳-玄武岩纤维复材筋/海水海砂混凝土/抗拉强度/退化机制/寿命预测Key words
CF-BF/Epoxy/seawater sea-sand concrete/tensile strength/degradation mechanism/life prediction引用本文复制引用
基金项目
国家自然科学基金山东联合基金项目(U1806225)
出版年
2024
NETL
NSTL
万方数据