超高速成像用于高冲击混凝土变形分析在裂变前后阶段
Applied optics
|January 16, 2024
概括
本研究评估了超高速摄像机用于分析冲击负载下混凝土变形和裂传播. 摄像机分辨率对高速材料测试的测量精度产生重大影响.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 光学工程是指光学工程.
背景情况:
- 高速成像对于分析动态物质在冲击下的行为至关重要.
- 评估图像质量对测量准确性的影响对于混凝土材料测试至关重要.
- 超高速摄像机为详细的变形和裂分析提供了潜力.
研究的目的:
- 评估三台超高速摄像机 (最高10Mfps) 的应用潜力,用于混凝土变形分析.
- 评估图像质量和相机规格对测量准确性的影响.
- 在曲和压缩试验中分析混凝土变形和裂纹传播.
主要方法:
- 使用的是Kirana 7M,Shimadzu HPV-X2 (ISIS传感器) 和Phantom TMX 7510 (BSI CMOS传感器) 的相机.
- 在混凝土样本上进行了三点曲和分裂-霍普金森压力棒测试.
- 应用移位矢量场分析用于变形测量和裂纹检测/跟踪.
主要成果:
- 在微秒尺度上测量了高达80微米 (曲) 和154微米 (压缩) 的变形.
- 在曲测试中确定了603-854 m/s之间的平均裂纹传播速度.
- 图像质量,空间和时间分辨率显著影响变形场,裂检测和跟踪精度.
结论:
- 超高速摄像机适用于分析混凝土变形和裂动态.
- 空间和时间分辨率是准确的高速变形测量的关键因素.
- 摄像机传感器技术和图像质量直接影响得出的几何测量的可靠性.
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