摘要
基于ACI 440.3R—04及ASTM D665—06规定的试验方法,分别开展了碱环境及海水环境下共70根玻璃纤维塑料(GFRP)筋抗拉性能的加速老化试验.结果表明:侵蚀183 d和365 d后,碱环境下GFRP筋的抗拉强度分别下降了48.81%和55.00%;而海水环境下其抗拉强度则分别下降了24.99%和30.55%;侵蚀环境及侵蚀时间对GFRP筋弹性模量影响不明显.结合加速老化试验结果及电子扫描电镜对腐蚀前后GFRP筋微观形貌的观测结果,对2种环境下GFRP筋的劣化机理进行了对比分析.结果表明,2种环境下GFRP筋劣化机理类似,劣化程度不同.其主要原因是OH-离子来源不同,浓度存在差异:碱环境中OH-离子是原有溶液中的,而海水环境中的OH-离子须通过树脂水解反应产生.
Using the experimental methods from ACI 440. 3R—04 and ASTM D665—06,the accelerated ageing experiment of tensile properties of 70 GFRP bars was done under alkaline and seawater environment. The experimental results show that after being eroded183 d and 365 d,the tensile properties of GFRP bars respectively decrease by 48. 81% and 55. 00% in alkaline environment,and respectively decrease by 24. 99% and 30. 55% in seawater environment,the influences of erosion environment and erosion time are not obvious on the elasticity modulus of GFRP bars. The microstructures of GFRP bars were observed using Scanning Electron Microscope before and after being eroded,the degradation mechanisms of GFRP bars were contrastively analyzed based on the accelerated ageing experimental results and the observed results. The analysis results show that the degradation mechanisms of GFRP bars in alkaline are similar to that in seawater environment. It is because that the sources and the concentrations of OH-ions are different,OH-ions in alkaline environment are from the original solution,while OH-ions in seawater environment are from the hydrolysis reaction of resin.
出处
《华北水利水电大学学报（自然科学版）》
2015年第1期38-42,共5页
Journal of North China University of Water Resources and Electric Power：Natural Science Edition
基金
国家"973"计划项目(2012CB0262000)
关键词
GFRP筋
碱环境
海水环境
抗拉性能
劣化机理
GFRP bars
alkaline environment
seawater environment
tensile properties
degradation mechanism
