Close-range photogrammetry applications in bridge measurement: Literature review

Close-range photogrammetry has found many diverse applications in the fields of industry, biomechanics, chemistry, biology, archaeology, architecture, automotive, and aerospace, as well as accident reconstruction. Although close-range photogrammetry has not been as popular in bridge engineering as in other fields, the investigations that have been conducted demonstrate the potential of this technique. The availability of inexpensive, off-the-shelf digital cameras and soft-copy, photogrammetry software systems has made close-range photogrammetry much more feasible and affordable for bridge engineering applications. To increase awareness of the use of this powerful non-contact, non-destructive technique in the bridge engineering field, this paper presents a literature review on the basic development of close-range photogrammetry and briefly describes previous work related to bridge deformation and geometry measurement; structural test monitoring; and historic documentation. The major aspects of photogrammetry bridge measurement are covered starting from the late 1970s and include a description of measurement types, cameras, targets, network control, and software. It is shown that early applications featured the use of metric cameras (specially designed for photogrammetry purposes), diffuse targets (non-retroreflective), stereoscopic photogrammetry network layout, and analog analytical tools, which transformed over time to the use of non-metric cameras, retro-reflective targets, highly convergent network layout, and digital computerized analytical tools.