Scanning laser in-depth heating infrared thermography for deep debonding of glass curtain walls structural adhesive

• Scanning in-depth heating IRT is proposed for deep debonding in glass curtain walls. • The method has a greater detection capacity for deep debonding than surface heating. • Thermal image process can effectively improve detected effect and SNR of images. • 10 mm × 8 mm debonding located 6 mm underneath can be successfully detected. For traditional infrared thermography (IRT) has a poor detection effect on deep defects, a novel infrared thermography method based on scanning laser in-depth heating was proposed to detect the deep debonding of hidden frame glass curtain walls structural adhesive which is located 6 mm underneath. The novel scanning laser in-depth heating thermography has advantages as follows: (1) scanning laser in-depth heating can heat the bonding interface of structure adhesive directly and has a greater detection capacity for deep debonding than surface heating; (2) the optimal detection scheme and parameters can get reasonable detection effect and prevent overheating which will cause structural adhesive performance degradation or damage; (3) thermal image reconstruction and integral enhancement can effectively improve detection effect and SNR of images. The test results demonstrated that the 10 mm × 8 mm debonding defect located 6 mm underneath form glass surface can be successfully detected.