Plane Coordinate Transformation between Gauss Projection and Oblique Mercator Projection for High-Speed Railway Surveying

In high-speed railway surveying,the projection length deformation should be less than 10mm/km during establishing the plane coordinate system.For the route which the direction is roughly towards east and west,the plane coordinate system by Gauss projection needs to be separated into multiple zones in order to control the projection length deformation,and this always produces multiple Gauss plane coordinate systems.However,oblique Mercator projection is able to meet the requirements of length deformation,as well as to solve the disunity problem in coordinate systems among these separated zones.This paper studies the transformation model from Gauss projection to oblique Mercator projection.Combined with the actual data measured from a high-speed railway,the results of calculation,analysis and practical application show that the method of this study is correct.