Janet Sham

Infrared Flash Thermography (Ft) for Building Diagnosis: Detection of Surface Cracks, Subsurface Defects and Water-paths in Building Concrete Structures Janet Sham

This is my MPhil thesis on the topic of using infrared flash thermography (FT) for detecting surface cracks, subsurface defects and water-paths in building structures. Infrared thermography was started to apply on building diagnosis in the early 19th century. In the beginning, video-recording is used for storing the infrared images and for visual analysis. Towards the 22 century, with the rapid improvements on technology, infrared signals are digitized and stored in computer for future analysis. Besides, the acheivements on developing infrared camera with higher sensivity and higher capturing frequency, small deviation on the temperature field of an object can be recorded and analyzed. Therefore, in this study, infrared flash thermography (FT) has been used to detect the three major building defects in concrete structures: surface cracks, subsurface defects and water-paths. The high capturing frequencies enabled and enhanced the detection of surface cracks. Moreover, the increase in sensitivity and digitization of infrared signals enbale post-processing. In this study, first and second deviations are applied which enhanced the detection of small temperature change on defected area.