早期固化和环境条件对混凝土收缩和微裂纹的影响
Magdalena Bacharz1, Kamil Bacharz1, Wiesław Trąmpczyński2
1Department of Material Strength and Diagnostics of Structures, Faculty of Civil Engineering and Architecture, Kielce University of Technology, 25-314 Kielce, Poland.
Materials (Basel, Switzerland)
|July 12, 2025
概括
这项研究表明,标准模型在湿固化条件下准确预测了混凝土收缩应变,但在空气干燥条件下没有. 声辐射 (AE) 监测有效地检测与收缩相关的内部损伤,有助于结构健康评估.
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
背景情况:
- 混凝土的收缩应变和内部损伤显著影响结构完整性.
- 预测具体行为的现有模型可能无法完全解释各种环境条件.
研究的目的:
- 分析固化和环境条件对混凝土收缩应变和破坏性过程的影响.
- 在不同的固化方案下评估EN 1992-1-1:2023模型的准确性.
- 通过声辐射 (AE) 监测,探索收缩应变和内部损伤之间的相关性.
主要方法:
- 在不同的固化 (水,空气干燥) 和温度 (恒定,循环) 条件下,用基岩聚合物和高炉水泥对C30/37混凝土进行实验测试.
- 在46天内使用延伸计测量收缩应变.
- 使用声辐射 (AE) 方法实时监测微裂变和内部过程.
主要成果:
- 标准EN 1992-1-1:2023模型准确地预测了湿混凝土的收缩应变,但显示了空气干燥混凝土的差异.
- 在早期混凝土中,收缩应变增加和AE过程增加之间建立了相关性.
- 确认了收缩应变和破坏性过程之间的强烈相关性,使得可以估计内部损伤.
结论:
- 该研究强调了需要改进的指导方针来估计在非标准环境条件下混凝土收缩应变.
- 非破坏性声辐射 (AE) 方法是诊断混凝土结构的早期损坏的宝贵工具,特别是那些面临不利条件的结构.
关键词:
美国 1992-1-1:2023年没有NDT的NDT.声学排放的声音排放.混凝土的收缩估计早期的年龄损伤.成熟 成熟 成熟 成熟.新的诊断方法新诊断方法没有装载/没有装载的混凝土.收缩时间 收缩时间标准 标准 标准 标准 标准更多相关视频
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