关于由CFRP板封闭的火灾后混凝土动态机械性能的实验研究
Jingya Liu1, Jingsi Huo2, Haitao Wang3,4
1Institute of Structural Material Failure and Strengthening Technology, Ningbo Polytechnic, Ningbo 315800, China.
Materials (Basel, Switzerland)
|May 11, 2024
概括
这项研究研究了火灾损坏的混凝土的动态机械性能,并用碳纤维增强聚合物 (CFRP) 板加强. 结果表明,CFRP的限制和高拉伸率提高了强度,这对于火灾后的结构修复至关重要.
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.
- 结构工程 结构工程
背景情况:
- 混凝土结构在暴露于火灾后容易受到显著的强度降解.
- 碳纤维增强聚合物 (CFRP) 复合材料为加强受损的混凝土元素提供了一个有前途的解决方案.
- 了解火灾后混凝土在冲击负荷下的动态行为,对于评估结构完整性和确保安全至关重要.
研究的目的:
- 评估火灾暴露,CFRP封闭和冲击速度对混凝土动态机械性能的影响.
- 分析使用CFRP限制的火灾后混凝土的应力-应变行为和能量吸收能力.
- 提出一个简化的模型来预测CFRP封闭的火灾后混凝土的动态压力强度.
主要方法:
- 分裂霍普金森压力杆 (SHPB) 实验设置用于进行冲击测试.
- 标本被置于不同温度下,以模拟火灾损伤.
- 用不同数量的CFRP层和不同冲击速度进行了测试,以评估它们的影响.
主要成果:
- 高温导致混凝土的压力强度产生软化作用.
- 碳复合材料的限制和延展率的增加表现出了硬化效应,显著增加了动态压力强度 (1.8到3.6倍的静态强度).
- 对于CFRP限制和延展率的影响,观察到不同的硬化机制和作用阶段.
结论:
- 碳复合材料的封闭和高拉伸率有效地提高了火灾后混凝土的动态压力强度.
- 拟议的简化模型可以帮助工程评估和火灾损坏的混凝土结构的紧急维修.
- 这项研究为设计和改造受火灾和撞击事件影响的混凝土结构提供了有价值的数据.
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