Tóm tắt:

In the bridge construction, height transíormation across river is an important work in the surveying. In the studied paper, it has been proposed that there be an interpolation method for the height anomalies of points in the axis from the results of the geometric leveling in points from the other bank of the river, located in the axial direction, and from satellite positioning results (GNSS technology) in these points and points to be interpolated. The number of points used to be interpolated may be two or three. In case of three poínts, the additìonal result of the interpolation over the triangle made by these points is obtained, allovving checking the results of the interpolation in the anomaly height of the given points. To ensure accuracy in determining the difference in two points' height in the axis at ±10 mm far from the banks, with the rìver width of about 1 km, the geometric leveling should be done at the accuracy level lũ and GNSS should be measured bý the static measurement with the mean square error of ±(5 mm+0.5 ppm) for the difference in height. The paper also determines the way to seíect the appropriate ratio in distance betvveen the interpolated point and the point in the other bank of the river, and in distance betvveen two interpolated points.