大规模多层钢筋混凝土梁的裂纹行为通过声辐射分析来描述
Yara A Zaki1, Ahmed A Abouhussien2, Assem A A Hassan1
1Department of Civil Engineering, Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John's, NL A1B 3X5, Canada.
Sensors (Basel, Switzerland)
|June 27, 2025
概括
声波排放分析量化了用化复合材料修复的钢筋混凝土梁的裂纹. 这项研究开发了一个损坏图,将声辐射参数与裂启动和故障阶段相关联.
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:
- 钢筋混凝土梁在屈曲负荷下容易发生裂纹.
- 工程混凝土复合材料 (ECCs) 提供增强的柔性和裂控制.
- 用先进材料修复现有混凝土结构对于延长使用寿命至关重要.
研究的目的:
- 为了评估大规模钢筋混凝土梁的裂变行为,用粉碎化 (CRECC) 和粉末化 (PRECC) 工程化水泥复合材料进行修复.
- 用声辐射 (AE) 分析量化裂传播和损伤阶段.
- 根据AE参数开发一个损害量化图表.
主要方法:
- 在修复和未修复的混凝土梁上进行了柔性测试,直到故障.
- 在整个曲试验中,采用了声辐射 (AE) 监测.
- 分析了AE数据,使用诸如命中,累积信号强度,b值,历史指数[H...t]和严重程度[Sr]等参数来评估裂纹.
主要成果:
- 在AE分析中,成功地确定了所有测试的梁中的第一个裂纹启动.
- 颗粒的大小 (碎片与粉末),维修位置和传感器位置显著影响了AE信号特征.
- 开发了一个损害量化图表,将AE强度参数[H,t,Sr]与不同的损害阶段 (第一个裂,最终负载) 相关联起来.
结论:
- 声波排放分析对于监测和量化修复混凝土梁的裂纹是有效的.
- 化工程混凝土复合材料显示出用于混凝土梁维修的潜力.
- 开发的损害量化图为基于AE数据的结构完整性评估提供了有价值的工具.
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