Diagnostic Imaging of Concrete Using Fusion of GPR and Ultrasonic Array Images

Presented by Thomas Schumacher, Portland State University Ultrasonic array echo (UAE) and ground penetrating radar (GPR) testing have been widely used in non-destructive testing (NDT) of concrete structures. In this research, have developed a comprehensive methodology to reconstruct and fuse images of the interior of concrete based on these two modalities, employing state-of-the-art medical image fusion techniques. Additionally, we have developed a set of image quality metrics that provide quantitative measures of the character and information content of the fused images. The work lays the foundation for an advanced yet practical imaging tool to evaluate concrete structures. In this presentation, the image comprehensive methodology is presented, fusion and image quality metrics are discussed, and results from laboratory specimens with different geometries and reinforcement details are evaluated. The proposed methodology results in enhanced images that are both visually more desirable for an inspector as well as they contain more information allowing for advanced data analysis techniques. Image quality metrics help to determine the most optimal fusion technique to be used for a given image. The findings to date underline the significance and opportunities that exist by transferring knowledge from the medical fusion domain to NDT and assessment of concrete structures.