Detection and characteristics estimation of defects in concrete structures using laser ablation-induced vibration
Detection and characteristics estimation of defects in concrete structures using laser ablation-induced vibration
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DOI：
10.1016/j.tust.2020.103460
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发表时间：
2020-09-01
影响因子：
6.9
通讯作者：
Yamaoka, Daiki
中科院分区：
文献类型：
--
作者：
Yasuda, Naotoshi;Misaki, Norikazu;Yamaoka, Daiki
本文提出了一种利用激光烧蚀引起的振动进行非接触式结构检查来检测和估计混凝土结构缺陷特征的方法，以防止局部剥落。使用两种类型的激光器：第一种是冲击激光器，用于在测量目标中引发振动；第二种是检测激光器，用于测量这些引发的振动。实验室测试使用有或没有内部缺陷的混凝土样本进行。结果表明，可以根据测量数据中阻尼振荡的发生来估计缺陷的存在。可以使用最小二乘复频域 (LSCF) 方法来确定是否存在这些阻尼振荡，这是一种用于模态识别问题的快速稳定参数估计方法。此外，当存在缺陷时，可以估计缺陷振动特性，例如固有频率和阻尼比。特别是，可以准确地估计固有频率。
This paper proposes a method for detection and estimation of the characteristics of defects in concrete structures using laser ablation-induced vibration for non-contact structural inspection to prevent partial spalling. Two types of lasers are used: the first is an impact laser that is used to induce vibrations in the measurement target and the second is a detection laser that is used to measure these induced vibrations. Laboratory tests are performed using concrete specimens with and without an internal defect. The results show that the presence of a defect can be estimated from the occurrence of damped oscillations in the measurement data. The presence or absence of these damped oscillations can be determined using the least-squares complex frequency-domain (LSCF) method, which is a fast-stabilizing parameter estimation method for modal identification problems. Additionally, when a defect is present, the defect vibration characteristics, such as natural frequencies and damping ratios, can be estimated. In particular, the natural frequencies can be estimated accurately.