Image-based detection and analysis of crack propagation in cementitious composites

The initiation and propagation of cracking in concrete and other cementitious materials is a governing mechanism for many physical and mechanical material properties. The observation of these cracking processes in concrete is typically taking place at discrete locations using destructive methods after the cracking process has occurred. The alternative nondestructive methods are often either not precise enough or experimentally too demanding. In this study, the use of an image analysis procedure to capture the crack initiation and propagation process is described, which utilizes digital images of the concrete while undergoing the cracking process. The results obtained with this method have shown that it is possible to monitor relatively small displacements on the specimen surface independently of the scale of the representative area of interest. The formed cracks are visible at relatively small crack openings, allowing a thorough investigation and analysis of the cracking processes in concrete.Fundação para a Ciência e a Tecnologia (FCT