Development of infra-red thermography NDT detection of defects in concrete and steel structures externally bonded with CFRP systems

This research investigates the ability of infra-red thermography (IRT) non-destructive techniques (NDT) to detect different defects involving unbond areas, debond areas, delamination, wet areas and cracks that may occur at the CFRP-substrate bond surface with concrete and steel structures. Extensive experimental qualitative and quantitative infra-red thermography assessments were carried out in this work. Numerical analyses were conducted to simulate and gain a better understanding of the key parameters that have the most influence on the thermal response of a defect within retrofitted surfaces. The results of the experimental and numerical studies serve as guidelines for thermographers to enable them to design the thermal load input to achieve desired thermal responses.