在结构正常重量的混凝土中,湿度对静态和动态弹性模块的影响
Lucyna Domagała1, Maria Margańska1, Marek Miazgowicz1
1Faculty of Civil Engineering, Cracow University of Technology, 31-155 Kraków, Poland.
Materials (Basel, Switzerland)
|August 10, 2024
概括
混凝土的湿度显著影响其静态弹性模量 (E),特别是在较弱的混凝土中. 这项研究揭示了湿度.
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
- 结构健康监测 结构健康监测
背景情况:
- 弹性的静态模量 (E) 对于结构分析至关重要.
- 超声波脉冲速度 (UPV) 方法通常用于估计E.
- 现有的方法往往忽略了混凝土水分对E.的影响.
研究的目的:
- 为了研究水分含量对正常重量结构混凝土的弹性 (E) 静态断面模量的影响.
- 为了比较通过静态和动态 (UPV) 方法获得的E测量的湿度灵敏度.
- 为了验证在不同的湿度条件下估计E的现有公式.
主要方法:
- 使用超声波脉冲速度方法测量了弹性 (E) 的动态模量.
- 静态断层弹性模量 (E) 通过直接测试钻过的核心来确定.
- 在不同的湿度条件下测试了两个正常重量的混凝土,其压力强度为51.6 MPa和71.4 MPa.
- 结果与以前获得的轻质聚合物混凝土数据进行了比较.
主要成果:
- 湿度含量显著影响了弹性 (E) 的动态模量,主要是在较弱的混凝土中 (51.6 MPa).
- 湿度对静态弹性模量 (E) 的影响不如预期明显,并且通常不显著,与一些文献相反.
- 静态和动态模块之间的湿度影响的差异归因于混凝土的密度结构和测量灵敏度.
- 验证了估计E的既定公式,在不同的湿度条件下显示了不同程度的准确性.
结论:
- 混凝土湿度对静态模量 (E) 的影响是复杂的,取决于混凝土强度和测量方法.
- 对于某些混凝土类型,UPV方法可能比直接的静态测试对湿度变化更敏感.
- 该研究强调了在结构混凝土评估中考虑水分含量的必要性,特别是在较弱的混凝土中.
- 这些发现为改进用于结构健康监测和混凝土财产估计的模型提供了有价值的数据.
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