使用近红外光成像检测混凝土的裂
Andreas Karpf1, Michael Selig1, Aktham Alchaar2
1Civil and Urban Engineering Department, New York University, Six Metrotech Center, Brooklyn, NY, 11201, USA.
Scientific reports
|November 3, 2023
概括
这项研究引入了一种新的光成像技术,用于检测混凝土结构中的裂. 该方法使用近红外光从远处可视化裂,改善结构健康监测.
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
- 光学工程是指光学工程.
背景情况:
- 民用基础设施的完整性依赖于结构性健康监测.
- 混凝土裂损害了耐用性,因为它允许环境剂透.
- 传统的裂检测方法在范围和可访问性方面存在局限性.
研究的目的:
- 为了研究光成像用于无接触地检测水泥材料中的裂.
- 克服传统裂检测技术的局限性.
- 开发一种用于在混凝土结构中早期识别裂的方法.
主要方法:
- 利用在混凝土表面上使用红光的浅角度冲击激发.
- 使用近红外摄像头对1140nm的混凝土光进行成像.
- 应用数字图像增强算法来检测细裂.
主要成果:
- 成功拍摄了从0.2-1.5毫米宽的人工裂,距离高达1.3米.
- 检测到0.08毫米的裂,比相机的像素分辨率 (0.1毫米) 更窄.
- 证明浅角光发射增强了裂的可见性作为黑暗的特征.
结论:
- 使用浅角红光激发的光成像对于远程混凝土裂检测是有效的.
- 该技术可以识别比成像系统的分辨率小的裂.
- 这种方法为混凝土基础设施的结构健康监测提供了有希望的进步.
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