Crack detection on retaining wall by using thermal camera and image processing technique

Abstract

Monitoring on geotechnical structure such as retaining wall, beams and dams is an essential task to retain its serviceability. One of the necessary component to be monitored is the presence of crack. In this paper, the potential of infrared thermography (IRT) as an operational tool for detecting cracks was tested and demonstrated on retaining wall. Two main work phase is employed in this study. First phase is focused on fieldwork which involve capturing the image by using infrared thermal (IRT) camera and digital single lens camera (DSLR). Second phase is focused on image processing technique by using a MATLAB numerical software. Targeted crack sample from the retaining wall have been scratched to observe the deformation of the crack before and after scratching. Analysis of the infrared thermal (IRT) image show that crack stand as cold area (low temperature) with respect to surrounding area. Disturbance of the heat flow allow the thermal camera to detect the presence of crack on retaining wall. Processing of the image extracted allows geometric characterization and direction of propagation of the crack through the wall to be determine. Within limited testing, detection and analysis of cracks is better with the proposed method because it is economical, can reduce time and involve no contacts. This paper presents a preliminary study for further inspection development on retaining wall.