Linear Fitting Of Old Highway Reconstruction

One of the key part of highway expansion project is fitting road liner according to the measurement data. But in our country, there have not enough mature and complete theoretical technology to finish Plane and longitudinal linear fitting road design in reconstruction. This paper systematically analyzed the methods of curve fitting and their respective characteristics and applicabilityRoad curve fitting is mainly about data collection, the curve parameter and selection of suitable fitting method. Linear identification method in foreign generally have curvature-arc length judging method and the slope discriminant method. Domestic generally have azimuth method and spline curve method,etc. The curve fitting methods used by Lagrange interpolation method, subsection interpolation method, spline fitting method and least squares, etc. By using least square method is the most feasible method according detailed comparison in applicability and accuracy.Reconstruction highway alignment fitting design is mainly about two aspects:one is horizontal alignment fitting, the other is cubes linear fitting design. By using least-square method, this paper expounds the principle of fitting design and process detailedly.The old road reconstruction line fitting design has many problems needing attention, such as fitting design methods, steps, principles, flat longitudinal surface combination, fitting linear evaluation and so on.This paper discusses the linear fitting design of old road reconstruction, based on least squares of longitudinal linear fitting flat design method, the principle and the problems should pay special attention, and combined with engineering example (tong guan-wei nan highway reconstruction project).