Research On Data Processing In CPⅢ Control Points Survey For Ballastless Track

When the high-speed railway had been developing in full swing, a solemnand profound warning was exposed to people at home and abrord by“7.23” Wenzhou train bullet collision. It need strict checks and wholeheartedly cooperation for the relevant authority to perfect the construction anddevelopment of high-speed railway. Ballastless track，with the character ofhigh evenness and straightness, is a vital factor that make sure the the trick runfast, safety and security, and the passengers comfortable. It is a a toughrequirement to ensure track laying evennessly and straightnessy to establishthe survey system of “three networks in one”, to improve the relative precisionof control networks of foundation pile(CPⅢ) to greatest extent.This dissertation will sketch out the survey system of “three networks inone”, elaborated the deployment and observation scheme of CPⅢ controlpoints, and then coarse adjustment and accurate adjustment of track.After thepreprocessing on observation data of CPⅢ control networks, it should bechecked to whether it is out of the accepted tolerance which is derivated in thepaper. Then the outline coordinate of CPⅢ control points and free stationingpoints in every zone can be calculated by means of side-angle resection. Thereasonable weight of each observation can be determined via multi-iterativeprocedure of Helmert variance component estimation. According thisreasonable weight, the coordinates of CPⅢ control points and free stationingpoints may be “attached” to the CPII and CPI control points by means ofquasi-stable adjustment zone by zone, meanwhile the evaluating precision. ofsingle zone can also be figured out. The coordinates of CPⅢ control points inoverlay region of adjacent zones could be smoothly lapped by means of cosinefunction method, which meet the demands of high evenness and straightnessfor CPⅢ control points in terms of line continuous mileage.After that, it is indicate that there are not only necessity and but possibilityto improve the precision of CPⅢ control points still further. Taking thequadratic term of Taylor’s series for nonlinear parameter estimation intoconsideration, we can get the higher-precision coordinates of CPⅢ control points and free stationing points with the method of least-square iterative. Thethe nonlinear least squares estimate based on genetic algorithm and improvedalgorithm is introduced to the coordinates calculation of CPⅢ controlpoints.At last，the advertent problem in data processing for CPⅢ controlpoints is stated in this paper, and so with some suggestions for future research.It also points out the limitations of the present thesis and provides somesuggestions for future research.