在固化和使用温度影响下,NSM CFRP 增强的 RC 结构中的预压力转移:实验验证和分析建模:实验验证和分析建模
Shuang Gong1,2, Peiqi He1, Ruogu Wang1
1Yunnan Science and Technology Research Institute of Highway, Kunming 650051, China.
Polymers
|September 27, 2025
概括
这项研究调查了温度如何影响碳纤维增强聚合物 (CFRP) 增强混凝土的前应力传导. 高温显著降低了粘合强度,影响了结构性能,需要仔细考虑设计.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
背景情况:
- 近表面安装 (NSM) 碳纤维增强聚合物 (CFRP) 复合材料用于加强混凝土结构.
- 这些复合材料的性能可能会受到环境因素的显著影响,特别是温度.
研究的目的:
- 为了检查在不同温度下NSM CFRP增强钢筋混凝土结构的前应力传递行为.
- 评估固化和使用温度对环氧粘合剂性能和结构性能的影响.
- 开发和验证一种分析模型,用于预测前应力转移长度和界面应力.
主要方法:
- 在不同的固化 (20-100°C) 和使用 (0-80°C) 温度下对环氧粘合剂进行实验测试.
- 开发一个分析模型,其中包含有效的结合度和预应力降低系数.
- 参数分析以确定影响预压力传输的关键因素.
- 对实验数据进行分析模型的验证.
主要成果:
- 在环氧粘合剂固化时间和温度之间存在一个反向指数关系.
- 粘合强度在60°C以上显著下降,在80°C时功能完全丧失.
- 开发的分析模型准确地预测了前应力转移长度,CFRP应变和界面剪切应力.
结论:
- 温度极大地影响NSM CFRP增强混凝土的粘合性能和前应力传递.
- 分析模型提供了一个可靠的工具,用于在热变化下设计这些结构.
- 优化CFRP增强结构的设计需要考虑在高温下粘合性能.
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