在混凝土中使用超声波非线性可达波干涉测量的压力损伤的评估
Shanchang Yi1, Chenglong Yang1, Xiangtao Sun2
1School of Civil Engineering, Changsha University of Science & Technology. Changsha 410114, China.
Ultrasonics
|August 22, 2024
概括
非线性可达波干扰测量 (NCWI) 通过克服缓慢动态的干扰来有效评估混凝土压缩损伤. 一个高效的非线性水平指标显示了与损伤的强烈相关性,证明了NCWIWI.
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.
- 地质物理学 地质物理学
背景情况:
- 混凝土表现出缓慢的动态,硬度下降和机械应力后的对数复原,使损坏评估复杂化.
- 非线性可达波干扰测量 (NCWI) 是一种对材料非线性敏感的技术,对损坏检测有潜在的用处.
- 混凝土中的压缩应力会产生非线性弹性效应,可以通过波传播方法进行探测.
研究的目的:
- 调查非线性可达波干扰测量 (NCWI) 的可行性,以评估混凝土中的压力损伤.
- 分析压力压力诱导的缓慢动态对NCWI测量的干扰效应.
- 使用NCWI. 建立一个可靠的指标来确定混凝土的压力损伤.
主要方法:
- 在不同的压力压力下对混凝土样本进行NCWI的实验验证.
- 慢动态现象的特征及其对波浪传播的影响.
- 开发和应用一个高效的非线性水平指标 (αdv/v).
- 使用常规波干扰测量 (CWI) 和直接波干扰测量 (DWI) 的比较分析.
主要成果:
- 卸载混凝土中的缓慢动力学显著干扰NCWI,与波相比显示相反的dv/v变化.
- 在缓解缓慢动力学后,有效的非线性水平 (αdv/v) 与压缩损伤有很强的相关性.
- 开发的指标 (αdv/v) 随着压力增加而成比例下降.
- 在评估混凝土压缩损伤方面,NCWI在CWI和DWI上表现出优势.
结论:
- NCWI是评估混凝土压力损伤的可行和有效方法.
- 了解和减轻缓慢动态干扰对于准确的NCWI结果至关重要.
- 有效的非线性水平 (αdv/v) 作为可靠的定量指标,用于具体的损害评估.
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