Research And Practice Of Topographic Survey Of A Water Conservancy Project In Chongzhou City

In this paper, a water conservancy project of Chongzhou is chosen to be surveying area. Introduced the plane control survey、elevation control survey and the researching of Topographic map measurement scheme and the implementation process and the analysis of the results. Plane control survey is the basis of the whole project plane coordinate measurement, This paper introduces the layout of the plane control survey scheme in the research and implementation, Through the scheme comparison, The project uses the static GPS observation method as the head plane control for survey, GPS control point of study, GPS baseline solution scheme, adjustment of GPS baseline solution and some of the problems in the process of the implementation of the scheme comparison and analysis. Finally, twelve GPS points are set according to Google Maps, and the fourth-grade GPS controlling network of the surveying area is established. GPS baseline calculating net adjustment scheme is optimized. At the same time the relationship between different coordinate system transformation parameters are calculated.Firstly,in the elevation control network scheme and implementation, wecomparison and analysis for the elevation control survey scheme, deciding to usethe leveling surveyfor head elevation control network layout and measured, some control points that leveling survey can’t closing use triangulated height measurement. Through the map design and field reconnaissance, four leveling points and eight GPS control points are chosen as joint-observation points. The other four plane control points are calculated through the method of electro-optical distance measurement. On the Measurement and calculation of leveling survey, this article introduces how to use electronic level for the measurement of leveling line, all the measurement results are adjustment calculated,it shows that this project has higher precision of leveling survey.On the survey of secondary control and detail survey, this article introduces how to use GPS for encryption of the root control points. The detail survey of the surveying area is preceded with RTK. In the digital mapping software, through two different methods for comparison and analysis,mainly introduced the triangulation interferometry in the advantage in the process of contour map.the topographic maps of the dam site of the surveying area 1:1000 and the reservoir area 1:2000 are completed. Lastly,this article focuses on unconventionality problem and solution in the process of this project.Through the above-mentioned research work, this article has done a lot of theory researching and technology practicing on horizontal control network, Elevation Control network and digital mapping of water conservancy project, this article has guiding significances for water conservancy topographic survey.