Phase Sensitive Detection and Classification of Defects in Concrete Structures by Ultrasonic and Electromagnetic Imaging Techniques

Many applications of imaging techniques like diffraction tomography demonstrate their ability to image the interior of huge structures like bridges. One problem of testing concrete bridges are grouting defects in tendon ducts which may lead to corrosion of tendons yielding a degradation of the stability of the whole structure. Ultrasound is able to penetrate the tendon ducts and therefore it may be used to image the interior, whereas electromagnetic waves are used for positioning. With the proposed phase detection technique the significance level of classification of indications can be considerably improved. Many applications of the technique will be given.