Development of flaw evaluation system for large civil structures by using low frequency ultrasonic wave and scattered waveforms

低频超声波与散射波形大型土木结构缺陷评价系统研制

• 批准号: 13555124
• 负责人: YAMADA Masaki
• 金额: $ 5.82万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13555124/
• 关键词: NDE; civil structures; ultrasonic wave; low frequency; imaging; scattering amplitude; concrete; linearized inverse scattering method; 非均質性; 欠陥評価; 形状再構成; 低周波数域超音波; 位相速度; 三次元弾性逆散乱法; 低周波超音波; 均質化法; 非均質材料; ミクロ構造; 磁歪センサー; 欠陥

The research about the technique of ultrasonic flaw reconstruction in elastic materials based on inverse scattering methods are carried out to develop a non-destructive evaluation system for large civil structures made by concrete materials.In this project, two and three dimensional elastodynamic inverse scattering methods are developed. The scattered wave measurement and the attenuation and phase velocity measurement were carried out for utilization of measured wave data. And, the comparison of reconstructed shapes by Born and Kirchhoff inverse scattering methods brought flaw characterization system.The shape reconstruction of flaws in the concrete materials by Born and Kirchhoff inverse scattering method is investigated. In this method, the angular and frequency diversities of the scattered waves are superposed in the form of the Fourier transform in the polar coordinate. An efficient method to accelerate the inversion process is proposed by rearranging the scattered wave data from the polar coordinate to the rectangular coordinate.The concrete specimens, that contain flaw models and has flat surface, are prepared and the scattered waveforms are acquired from the pulse-echo measurement. The performance of the shape reconstructions is shown for flaw models is the prepared specimens.As the result, the possibility of this method to reconstruct the shape of flow in concrete materials is shown.

开发了基于反散射方法的弹性材料中超声缺陷重建技术的研究，以开发一种由混凝土材料制造的大型民用结构的非破坏性评估系统。进行了散射的波测量以及衰减和相速度测量，以利用测量波数据。并且，通过出生和Kirchhoff反向散射方法对重建形状进行比较带来了缺陷的表征系统。研究了混凝土材料中缺陷的形状重建和Kirchhoff逆散射方法。在这种方法中，散射波的角度和频率多样性以极坐标中的傅立叶变换的形式进行了超级序列。提出了一种加速反转过程的有效方法，是通过将散射的波数据从极坐标重新安排到矩形坐标。为缺陷模型显示了形状重建的性能是制备的样品。结果，显示了这种方法重建混凝土材料中流动形状的可能性。

项目成果

Yamada, M., Murakami, K., Nakahata, K., Kitahara, M.: "Three-Dimensional Flaw Reconstruction from Waveforms Measured on the Side of a Cylinder"J.Applied Mechanics JSCE. 6. 69-76 (2003)

Yamada, M.、Murakami, K.、Nakahata, K.、Kitahara, M.：“根据在圆柱体侧面测量的波形进行三维缺陷重建”J.应用力学 JSCE。

M.Yamada: "Three dimensional shape reconstruction of defects from measured backscattering wave forms"Inverse Problems in Engineering Mechanics. III. 137-144 (2002)

M.Yamada：“根据测量的反向散射波形重建缺陷的三维形状”工程力学反问题。

M.Kitahara, K.Nakahata, S.Hirose: "Elastodynamic inversion for shape reconstruction and type classification of flaws"Wave Motion. 36. 443-455 (2002)

M.Kitahara、K.Nakahata、S.Hirose：“用于缺陷形状重建和类型分类的弹性动力学反演”波运动。

Terada, K., Kikuchi, H.: "A class of general algorithms for nonlinear multi-scale analyses of heterogeneous media"Computer Methods in Applied Mechanics and Engineering. 190. 5427-5464 (2001)

Terada, K.、Kikuchi, H.：“异质介质非线性多尺度分析的一类通用算法”应用力学与工程中的计算机方法。

K.Nakahata, M.Onishi, M.Kitahara: "Application of Linearized Inverse Scattering Methods to the Material with Flat Measurement Surface"Review of Progress in Quantitative Nondestructive Evaluation. 22. 726-733 (2003)

K.Nakahata、M.Onishi、M.Kitahara：“线性化逆散射方法在具有平坦测量表面的材料上的应用”定量无损评估进展综述。