文献类型：期刊文献

英文题名：Low-frequency ultrasonic array imaging for detecting concrete structural defects in blind zones

作者：Yang, Jingjing[1];Fan, Guopeng[1];Xiang, Yanxun[2,3];Zhang, Haiyan[4];Zhu, Wenfa[1,2];Zhang, Hui[1];Li, Zaiwei[1]

机构：[1]Shanghai Univ Engn Sci, Sch Urban Railway Transportat, Shanghai 201620, Peoples R China;[2]East China Univ Sci & Technol, Sch Mech & Power Engn, Shanghai 200237, Peoples R China;[3]Shanghai Key Lab Intelligent Sensing & Detect Tech, Shanghai 200237, Peoples R China;[4]Shanghai Univ, Sch Commun & Informat Engn, Shanghai 200444, Peoples R China

年份：2024

卷号：425

外文期刊名：CONSTRUCTION AND BUILDING MATERIALS

收录：;EI(收录号：20241515869168);WOS:【SCI-EXPANDED(收录号:WOS:001225080800001)】；

基金：The work was supported by the National Key Research and Devel- opment Program of China (Grant No. 2022YFF0605604) , National Natural Science Foundation of China (Grant Nos. 12304514, U1930202, 12374443, 12174245, 12004240 and 12104290) .

语种：英文

外文关键词：Defect detection; Concrete structures; Blind zones; Low -frequency ultrasonic array; Diffusion attenuation compensation; Solid directivity correction

摘要：Ultrasonic array (UA) imaging is a promising non-destructive testing (NDT) method that is extensively used for defect detection. Due to the high attenuation characteristics of ultrasonic wave propagation in concrete structures and the directivity of sensors, the total focus method (TFM) easily misses specific defects in blind zones that are far from the sensors or located at a large deflection angle. To overcome this limitation, the diffusion attenuation compensation factor and solid directivity correction factor are adopted to improve the scattered signal energy of defects that are in blind zones. On this basis, the diffusion attenuation compensation method (DACM), the solid directivity correction method (SDCM), and the diffusion attenuation compensation-based solid directivity correction method (DAC-SDCM) are proposed. These methods are applied to characterize multiple circular holes in concrete structures using the dry point contact (DPC) low-frequency UA, and the detection results are evaluated from the intensity curve and detection area of ultrasonic images. The numerical and experimental results indicate that DACM is suitable for detecting defects located at longer distances, SDCM is capable of detecting defects located at larger deflection angles, and DAC-SDCM can significantly improve the detection performance of defects that are distant and have large deflection angles. The findings demonstrate that the proposed methods can significantly improve the detection ability of defects in blind zones and broaden the application of DPC low-frequency UA in the health monitoring of concrete structures.