Abstract
Many highway bridges constructed during the high economic growth period have become deteriorated. So their maintenance is required. However, they are facing difficulties in maintenance because their drawings prepared at the time of design or completion were made in paper media, many of which have already been disposed. There is a research that attempts to automatically generate SXF (Scadec data eXchange Format) drawings of a highway bridge to use for its maintenance, using point cloud data obtained by MMS (Mobile Mapping System). In the previous research, the authors use positions of joints on a bridge to divide a point sequence into each span and generate their alignments of the highway bridge. However, when it is unable to extract a joint, or when the start and end points of the alignment are placed at a short distance from the positions of joints on a design drawing, the generated clothoid curve will lose continuity with straight line and circular arc. Thus, this research proposes an analysis method for calculating the start and end points of straight lines, clothoid curves, and circular arcs in a plane and straight lines and quadratic curves in a longitudinal section to allow each alignment to connect with each other naturally. This allows generating the SXF drawings of the superstructure on a highway bridge with high precision without considering the positions of joints.
