New algorithm for fitting 3D highway alignment from geometric data

Much research on algorithm for fitting highway alignment has been conducted. However, there are also some limitations e.g. hard to collect the source data, high cost, etc. From the point of view of traffic safety assessment techniques of highway alignment, new algorithm for fitting highway alignment is put forward. And the mathematic model and calculation steps of three-dimensional (3D) coordinates and the fitting method of 3D highway alignment are expounded in detail. Then case studies and error analysis of the algorithm are implemented. The algorithm is considered more efficiency, higher accuracy and easier to get the source data etc. than previously developed approaches. The core of the algorithm is using horizontal and vertical geometric data to calculate 3D coordinates, generate control points sequence, and using cubic B-spline approximation to fit 3D highway alignment.