结构轻质混凝土的湿度状况对静态和动态弹性模块的指定值的影响
Lucyna Domagała1, Kinga Sieja1
1Faculty of Civil Engineering, Cracow University of Technology, 31-155 Kraków, Poland.
Materials (Basel, Switzerland)
|June 28, 2023
概括
混凝土的湿度显著影响弹性测量的模量. 这项研究表明,湿度对动态模量的影响比静态更大,因此需要将其纳入轻质聚合混凝土 (LWAC) 的计算.
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:
- 超声波脉冲速度的动态弹性模量 (E) 通常用于估计建筑中的静态模量 (E).
- 现有的估计方程往往忽视了混凝土含水量的关键影响.
- 轻质聚合混凝土 (LWAC) 具有独特的特性,可能会受到湿度变化的影响.
研究的目的:
- 量化水分含量对结构LWAC的动态和静态弹性模量的影响.
- 评估LWAC强度和密度的变化如何影响湿度对模量测量的影响.
- 为了确定当前估计方法是否需要调整以考虑LWAC湿度.
主要方法:
- 测试了两系列具有不同强度 (40.2和54.3 MPa) 和密度 (1690和1780 kg/m3) 的结构LWAC.
- 使用超声波脉冲速度测量弹性的动态模量.
- 通过既定的测试程序测量弹性静态模量.
- 在空气干燥和水和条件下进行测量,以评估湿度影响.
主要成果:
- 与静态模量相比,LWAC水分含量的影响在动态模量测量上明显明显.
- 静态模量在空气干燥条件下平均低于动态模量11%,在水和条件下低于动态模量24%.
- 观察到的湿度对静态-动态模量关系的影响在不同类型的LWAC.测试中是一致的.
结论:
- 湿度含量是一个关键因素,必须在测量和估计LWAC的弹性模量时考虑.
- 从动态模量 (通过超声波脉冲速度) 估计静态模量所用的方程应该修订,以纳入混凝土的水分水平.
- 精确的LWAC材料表征需要考虑其湿度状态,以确保可靠的结构性能预测.
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