碳纤维增强聚合物钢筋在高温下保持强度
Hyun-Do Yun1, Seung-Yun Lee2, Dae-Hee Kang2
1Department of Architectural Engineering, Chungnam National University, Daejeon, 34134, Republic of Korea.
Scientific reports
|May 19, 2025
概括
碳纤维增强聚合物 (CFRP) 铁杆在高温下显著损失强度,在550°C时仅保持33%的拉伸强度. 这项研究为使用CFRP钢筋的耐火混凝土结构提供了关键数据.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 聚合物科学 聚合物科学
背景情况:
- 碳纤维增强聚合物 (CFRP) 钢筋越来越多地用于建筑.
- 了解它们在高温下的性能对于消防安全应用至关重要.
- 冲压制造在CFRP钢筋中提供了增强的热稳定性和树脂分布.
研究的目的:
- 为了研究在高温 (25-550°C) 下制CFRP钢筋的机械行为.
- 为了评估抗拉强度,弹性模量和剪切强度的降解.
- 将实验结果与现有的经验方程进行比较,并确定热降解阶段.
主要方法:
- 在CFRP钢筋上进行了拉力和剪切强度测试.
- 测试覆盖了从环境 (25°C) 到550°C的温度范围.
- 分析了结果,以确定强度保留和降解模式.
主要成果:
- 在350°C以上观察到拉伸和剪切强度的显著降解,与分解阶段相吻合.
- 在550°C时,大约33%的初始拉伸强度和20%的初始切割强度被保留.
- 弹性模量在550°C下降约20%,显示的灵敏度低于强度.
- 拉力和剪切强度都没有达到零,表明在热应力下的残余能力.
结论:
- 在高温下,特别是超过350°C时,CFRP钢筋经历了相当大的机械性质损失.
- 确定了与温度相关的强度保留的三个不同的阶段.
- 该研究为设计耐火纤维增强聚合物 (FRP) 钢筋混凝土结构提供了必要的数据.
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