在不同温度下对混合纤维钢筋混凝土的动态机械性能进行实验研究
Gejun Tong1,2, Jianyong Pang3, Bin Tang1
1School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, Anhui Province, China.
Scientific reports
|May 9, 2025
概括
这项研究优化了使用大米灰和纤维的混合纤维钢筋混凝土 (HFRC). 优化的HFRC显示了增强的机械性能和在高温下优异的性能,提高了混凝土结构的弹性.
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.
- 混凝土技术 混凝土技术
背景情况:
- 混合纤维增强混凝土 (HFRC) 提供了改善机械性能的潜力.
- 了解构成材料和环境因素对HFRC应用的影响至关重要.
- 现有的研究往往侧重于单个组件,需要对协同效应进行全面研究.
研究的目的:
- 量化研究大米灰含量,聚烯纤维和钢纤维体积分数对HFRC机械性能的影响.
- 通过使用Split Hopkinson Pressure Bar (SHPB) 技术在各种温度梯度下检查HFRC和普通混凝土 (OC) 的动态机械行为.
- 阐明温度和应变速率对HFRC动态机械性能的相互作用影响机制.
主要方法:
- 使用直角设计实验,系统地改变米灰含量和纤维体积分数.
- 使用Split Hopkinson Pressure Bar (SHPB) 技术来评估冲击负荷下的动态机械性能.
- 进行了高温测试,以评估HFRC和OC在热应力下的性能.
主要成果:
- 发现钢纤维含量是HFRC压力和拉伸强度的主要决定因素.
- 聚烯纤维显著提高了HFRC的拉力性能.
- 使用12%的水皮灰,0.1%的聚烯纤维和0.5%的钢纤维实现了最佳性能,压力强度增加10.41%和拉伸强度增加50.22%.
- 与OC相比,HFRC在高温条件下表现出优越的机械性能和动态响应特性,强度参数最初下降,然后随着温度升高而增加.
结论:
- 该研究确定了HFRC的最佳组成,显著提高了其压力和拉伸强度.
- 与普通混凝土相比,HFRC具有显著的弹性和优越的机械性能,特别是在高温和动态负载条件下.
- 这些发现为开发防灾混凝土结构为火灾环境提供了科学基础.
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