Research On Surveying Technology Of GRN In High-Speed Railway

High-speed railways are being constructed on a large scale in our country recent years. Surveying researchers build up the system of surveying technology of precise control in high-speed railway gradually based on the absorption and innovation of foreign surveying technology. GRN is a surveying control network for the CRTSⅡ track construction which comes from MAX BOEGL CONSTRUCTION LTD(Germany). There is a big difference between GRN technology and traditional surveying technology of precise control. Many problems are not solved in the surveying technology of GRN. From surveying point of the view, track regularity is a kind of system error which is accepted. There is an objective relationship between track regularity and GRN surveying technology. Traditionally, surveying technology of precise control weakens system error in measurement as far as possible. While the plane surveying of GRN which accuracy is submillimeter works by the method of half-face observation, and the elevation measurement of GRN adopts the method of intermediate-sight leveling. Both of the methods don’t take any measures to control the influence of the main system errors. There will be a GRP set on the Central Line of high-speed railway every6.5m. GRP is set on left and right lines separately. The work of surveying GRN is very heavy.According to the questions of the theoretical and practice on the surveying technology of GRN, this paper mainly researches the four contents following:Firstly, According to the importance of track regularity to the construction of high-speed railway, the paper analyzes the relationship between track regularity and surveying technology of GRN, and discusses relative accuracy of GRN plane surveying and elevation surveying allowed and parts of the accuracy performance. A suitable surveying net is recommend after discussing the difference of the two surveying net for connecting CPⅢ. Secondly, the surveying method of GRN imported from Germany allows system errors existing in the measurement from beginning to ending. This paper analyzes the impact of main system errors existing in the method of half-face observation and the method of intermediate-sight leveling on the track regularity. The result shows that the main system errors of the method of half-face observation almost don’t produce adverse influence on alignment regularity, and system errors in intermediate-sight leveling will cause adverse effect on high and low regularity. Thirdly, the measurement of GRN has heavy workload. In view of the problem, this paper discusses the key technology of trigonometric leveling instead of leveling in the elevation surveying. The data of trigonometric leveling is processed and relative accuracy of elevation is evaluated. Fourthly, according to the characteristics of GRN, the paper puts forward to a mathematical model of high degree automation for software of plane data acquisition. A new software for GRN data processing is edited according to the result of this paper.