Application of Close-Range Terrestrial Photogrammetry to Bridge Structures

摘要

A field application of close-range terrestrial photogrammetry to the measurement of small order of magnitude structural displacements and differences in elevation was conducted. A Jena UMK 10/1318 camera was used to take the photographs used in the evaluations. Measurements of the deflections of steel girders on several bridges suggest that accuracies on the order of 1/8 in. can be achieved with normal care using the UMK 10/1318 camera. In addition, close-range terrestrial photogrammetry can be used for other bridge applications such as for deck condition surveys. By using this technique for condition surveys, the need for taking hand measurements and preparing sketches in the field is eliminated. The photographs provide a permanent record which can be used as a reference to evaluate potential changes in the condition of the deck or to gage structural movements.