A study on improving accuracy of cadastral overlapping map in railway project

A railway is a linear type project of narrow width that extends more than a few kilometers in the vertical and horizontal directions. A continuous cadastral map is used to determine the boundary of a railroad during implementation design. However, if a cadastral line and boundary of railroad are discordant at the point of land compensation, problems such as change notices of the project, construction period delay, and additional cost can arise. Due to the use of continuous cadastral maps and individual cadastral maps created by different standards, such as surveying coordinate system, surveying origin, and triangulation point, KR requested LX to perform surveying to designate a line and cadastral overlapping map to solve the inconsistency problem. This study attempted to improve the accuracy of cadastral overlapping map in implementation design. It used 90 points around one railway line, divided models by collective and district, and carried out coordinate transformation. The RMSE of the batch application model was 0.1372, and the RMSE of the district model was 0.0245. Therefore, it can be deduced that this method provides a way to reduce error by calculating and applying the number of coordinate systems in each district when creating a cadastral overlapping map.