Abstract: In view of the low efficiency of leveling section in the highway with large undulation, this paper uses the method of RTK and partition plane fitting to solve the problem of elevation anomaly transformation in the belt terrain. Based on the CORS, it is enabled to acquire the accuracy of 3 cm of plane error for determining the center line of road and collecting the GPS coordinate of road cross-section. In order to solve the problem of height anomaly, we use stepwise selection method to select the best location of control point and partition plane fitting method for changing GPS elevation into normal elevation, and the accuracy of elevation transformation is less than 5 cm.

Key words: elevation fitting, partition plane fitting, cross-sectional measurement, RTK, CORS