Abstract
This paper presents a study on monitoring method of crack width on concrete structures using digital photogrammetry. In this measurement procedure, the reflective targets are installed at measurement points around the crack as the gauges, and the deformation of crack width is calculated from one image taken from arbitrary camera positions. In this paper, we verify the relation between the accuracy/precision and the distance/angle of photographic positions from the targets in experiments, and the results showed that it was possible to measure the displacement of crack about 0.1mm at 100m and 30 degree photographic angle. Moreover, application of this method to measuring crack changes on actual concrete structures showed that it was possible to monitoring of the structures easily by using this method.
