This chapter is devoted to the pulsed stimulated infrared thermography technique applied to the detection and the characterization of the depth and width of adhesion defects (delaminations or adhesive disbonds) of FRP externally bonded on RC structures. In a first part, the principle of pulsed stimulated infrared thermography is recalled ; laboratory investigations are then presented in a second part. The laboratory samples contain different defects (with calibrated size and depth) inserted between the concrete substrate and the carbon FRP laminate bonded to its surface. Experiments were conducted in laboratory on the dedicated samples and complementary 2D numerical simulations were also carried-out. Analysis methods of thermograms are presented. Thermal signatures of different geometries of defects are studied in the cases of pulse and square heating thermal excitations. Main advantages of each stimulated technique are discussed in relation to the targeted application. Results from experiments based on long pulse approach are also discussed in details. In the second part of this chapter, a case study of field application is presented for the proposed method. Inspection is carried-out using a hand-held heating device and an infrared camera. Such a simple technology enables real time NDE in the field with a high efficiency.
