Development of grobal ultrasonic nondestructive testing methods using surface waves and Lamb waves

表面波和兰姆波全球超声无损检测方法的开发

• 批准号: 07555636
• 负责人: HIROSE Sohichi
• 金额: $ 0.9万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555636/
• 关键词: propagation and scattering of elastic waves; quantitative nondestructive evaluation; ultrasonic wave; numerical simulation; boundry element method; inverse analysis; reconstruction of defect shape; inversion for surface breaking crack; 超音波非破壊検査

The main results obtained in this project are summarized as follows :1. Development of computational software for wave analysis and numerical simulations : Boundary element programs are developed for propagation and scattering of elastic waves in a plate and a waveguide. Far field expressions of Green's functions are used to improve the accuracy of the near field solutions around defects and to botain the scattered properties for various incident wave modes and defect configurations.2. Inverse scattering analysis an d visualization of defects : Linearized inversion analyzes based on the Born approximation and Kirchhoff approximation are developed for the reconstruction of defect shapes from detected ultrasonic data. In the numerical simulation, the inverse analyzes are applied to 2-D and 3-D defects in a solid and are investigated for the applicability for scattered data with the limited aperture problem. The inverse methods are also applied to experimental data obtained from immersed ultrasonic testings. The shapes of defects are reconstructed with good resolutions except for the case that adjacent defects are too closely located each other.3. Nondestructive measurement for a surface breaking crack in concrete : An inverse method to evaluate the depth and angle of a surface breaking crack is proposed using the characteristics of diffracted waves at the crack edge. The applicability of our method is verified in the numerical simulation using BEM and on-the-site experiments.

本课题取得的主要成果如下：1.开发用于波动分析和数值模拟的计算软件：开发用于板和波导中弹性波传播和散射的边界元程序。利用绿色函数的远场表达式，提高了缺陷附近近场解的精度，得到了不同入射波模式和缺陷结构的散射特性.缺陷的逆散射分析和可视化：基于Born近似和Kirchhoff近似的线性化反演分析被开发用于从检测的超声数据重建缺陷形状。在数值模拟中，反分析被施加到2-D和3-D的固体中的缺陷，并研究了有限孔径问题的散射数据的适用性。反演方法也适用于从浸没超声检测获得的实验数据。除了相邻缺陷位置太近的情况外，缺陷的形状重建具有良好的分辨率.混凝土表面破裂裂缝的无损检测：利用裂缝边缘绕射波的特性，提出了一种估算表面破裂裂缝深度和角度的反演方法。通过边界元数值模拟和现场试验验证了该方法的适用性。

项目成果

片岡秀起: "SH板波の散乱解析" 土木学会中国支部平成8年度研究発表会講演概要集. (1996)

Hideoki Kataoka：“SH 板波的散射分析”日本土木工程师学会中国分会 1996 年研究报告摘要（1996 年）。

S.Hirose: "Ultrasonic inversion for determining crack size in a solid" J.Faculty of Environ.Sci.and Tech., Okayama Univ.Vol.2. 89-98 (1997)

S.Hirose：“用于确定固体中裂纹尺寸的超声波反演”J.Faculty of Environ.Sci.and Tech.，冈山大学，Vol.2。

M.Nakamura: "Development of new on-line inspection technique of steel strips using real-time digital signal processing" 8th Int.Symp.on Nondestructive Characterization of materials. (1997)

M.Nakamura：“利用实时数字信号处理开发新型钢带在线检测技术”第 8 届材料无损表征国际研讨会。

S.Hirose: "Inverse scattering for reconstruction of cavities" J.Struct.Eng.Vol.43A. 453-460 (1997)

S.Hirose：“用于重建空腔的逆散射”J.Struct.Eng.Vol.43A。

廣瀬壮一: "SH板波の散乱解析への境界要素法の応用" 境界要素法論文集. 14. 43-46 (1997)

Soichi Hirose：“边界元法在 SH 板波散射分析中的应用”边界元法论文集 14. 43-46 (1997)。