English

In road maintenance, it is necessary to construct an environment that manages three-dimensional data and maintenance information for its effectivity and efficiency. The primary objective of this research is to support road maintenance work using three-dimensional data by combining point cloud data of terrestrial laser scanning and unmanned aerial vehicles (UAV) with photogrammetry. For on-site surveying, the limitations have been clarified. The first limitation is based on site circumstances. Passengers and cars use the road being surveyed during measurements. There are few berms and little space for setting a terrestrial laser scanning. In addition, locations where instruments can be placed are limited. It is difficult to perform the number of measurements necessary for acquiring point cloud data. The second limitation is the measurement range, given the specifications of the instrument functionality for pavement surveys. The experimental results indicate that the high-density measurement range is restricted to within an approximately 10-m radius. Based on these limitations, the upside of a slope or a landform is surveyed using a camera mounted on a UAV. Point cloud data for these objects are constructed using photographs with SfM technology. SfM data and terrestrial laser scanning data are combined because three-dimensional data for bridge sides and lower works cannot be constructed. To evaluate the accuracy of three-dimensional data, we compare the three-dimensional data with its design conditions. The inaccuracy for the bridge is an effective length of 12 mm and an effective width of 19 mm and the three-dimensional data describes the structure of the bridge with high accuracy. The three-dimensional data for the road structures could be used to develop a road maintenance management system that accumulates data and refers to the inspection results and repair information in three dimensions.