| 摘要: |
| 为了探究玻璃纤维增强复合材料（GFRP）筋在模拟和真实混凝土环境中性能衰退的规律及机理，设置了碱溶液（AS）和混凝土包裹GFRP筋后置于自来水中（CS）2种侵蚀环境，采用短梁剪切法分析了GFRP筋力学性能的衰退规律，并借助扫描电子显微镜、差示扫描量热法分析了GFRP筋的微观结构和玻璃化转变温度（Tg）.结果表明：随着温度的升高，GFRP筋层间剪切强度衰退的速率加快；GFRP筋在60 ℃的AS中老化183 d后层间剪切强度保留了48.6%，Tg降低了9.2%，部分纤维与树脂脱黏，树脂出现孔洞；相同条件下CS中GFRP筋的层间剪切强度保留了61.4%，Tg降低了3.4%，纤维产生浅坑.基于Arrhenius方程建立了北京地区GFRP筋的性能预测模型. |
| 关键词: 玻璃纤维增强复合材料筋 混凝土环境 微观结构 玻璃化转变温度 预测模型 |
| DOI：10.3969/j.issn.1007-9629.2023.02.007 |
| 分类号:TU532 |
| 基金项目:山东省重点研发计划项目（2019GHZ015）；中央引导地方科技发展资金项目（YDZX20193700004703） |
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| Degradation Law and Mechanism of GFRP Bars in Concrete Environment |
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LI Wenchao1,2, ZHOU Guangfa3, WEN Fusheng1, LIU Fusheng2, JIAO Yuzhao4
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1.College of Mechanical and Architectural Engineering， Taishan University， Taian 271000， China;2.College of Water Conservancy and Civil Engineering， Shandong Agricultural University， Taian 271018， China;3.Shuifa Planning and Construction Co.， Ltd.， Jinan 250100， China;4.Shandong Safety Industrial Co.， Ltd.， Taian 271000， China
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| Abstract: |
| The performance degradation rule and mechanism of performance of glass fiber reinforced polymer（GFRP） bars in simulated concrete pore solution and real concrete environment were explored. The GFRP bars were conditioned in two different ways. The first part of GFRP bars were immersed in alkali solution（AS） and the second part of GFRP bars were wrapped with concrete and then submerged in tap water（CS）. The mechanical property degradation of GFRP bars was analyzed by using short beam shear method. Microstructure and glass transition temperature（Tg） of GFRP bars after aging in two environments for 183 days were analyzed using scanning electron microscopy and differential scanning calorimeter respectively. The results demonstrate that the degradation rate of GFRP bars increases with the increase of temperature. After 183 days aging treatment at 60 ℃ in AS environment， the interlaminar shear strength of GFRP bars is retained at 48.6%， Tg is reduced by 9.2%， the separation between fiber and resin is observed and a few holes may be seen in the resin. However， after the same treatment of GFRP bars in the CS environment， the interlaminar shear strength of GFRP bars is retained at 61.4%， Tg is reduced by 3.4%， and the fibers has shallow pits caused by erosion. Finally， the durability prediction model of GFRP bars serving in Beijing is established by using Arrhenius equation. |
| Key words: glass fiber reinforced polymer bar concrete environment microstructure glass transition temperature prediction model |
