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Research on Precision,Measurement, Reconstruction and Optimal Adjustment of Raising Speed Railway

Author: ChenFeng
Tutor: YangYue
School: Central South University
Course: Traffic and Transportation Engineering
Keywords: raising speed railway precision measurement adjustmentconstruction plane reconstruction profile reconstruction
CLC: U212
Type: PhD thesis
Year: 2013
Downloads: 76
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Abstract

The track regularity has an important influence on the running quality of the train. The raising speed railway has much more stringent requirements of track regularity. Currently, the detection and maintenance of long-wave regularity based on the raising speed railway are still lack of effective approaches and means. On the basis of the analysis of relevant research status at home and abroad, raising speed railway precise measurement and regularity maintenance technology are researched to form a set of theories, methods on track precise measurement, optimal reconstruction and precise adjustment, based on CPⅢ precise control network. The main research contents include:Aimed at the measurement requirements of long-wave regularity, a raising speed railway measurement technology plan based on CPⅢ precise control network is proposed. The compensating computation model of free-station of total station and stability test model of CPⅢ control point are introduced, which provide the accurate data source for continuous precise measurement and optimal reconstruction of railway three-dimensional space coordinates.On the basis of total station coordinates, prism measurement data and track inner geometric detection data, the space coordinate calculation model of track central line has been constructed based on the three-dimensional coordinate transformation. Considering the coarse noise in track inner geometric detection data, three-scale wavelet decomposition method based on DB1wavelet is utilized to decompose detection data, and3a criteria is used to identify and eliminate the high-frequency components of the signal, then the detection data is reconstructed using wavelet in order to filter out the noise signal in the track geometry detection data.In order to achieve the optimal reconstruction of plane curve, the mileage and offset distance calculation model, which is modeled on least square fitting of straight line between curves, is built. The optimal reconstruction model of continuous plane curve is built using intersection of straight line between curves, curve radius and length of transition curve as optimization goals. By using the reconstruction result of single plane curve as the initial optimal solution, a Powell-PSO hybrid optimization algorithm is proposed to achieve the optimal reconstruction calculation of continuous plane curve parameters.In the study of profile optimal reconstruction, the weighted coefficients of lift and pressure amount are introduced and the optimization model of profile continuous slope is built, the minimum lift and pressure mount is used as optimization objective, the mileage and elevation of gradient change points are used as optimization variables. Using the linear least square fitting construction result of profile single gradient as initial optimal solution, PSO optimization algorithm is utilized to achieve the optimal reconstruction calculation of continuous slope. On this basis, the optimal model of vertical curve is designed. The optimization of vertical curve radius is achieved by fixed step iterative search methods.Considering the adjustment requirements of long-wave and short-wave regularity of raising speed railway, according to the line precision measurement data and reconstruction result, an optimal adjustment program of line plane and profile is built which fits the construction of tamping machine. On this basis, the adjustment program of long-wave and short-wave regularity for special sections (such as switch section, eccentric bridge section, and steel beam bridge section) is further designed.The CPIII precise measurement and adjustment trial network is built in the region from K40to K65of Guangzhou-Shenzhen Railway with the speed of200km/h to verify the work of this paper. The absolute coordinate measurement based on CPIII precision control network is completed in the trial region, and the parameters of plane curve and profile are reconstructed. Then the reconstructed parameters are utilized to formulate the adjustment plan of plane and profile which meet the regularity of long wave and short wave. The contrast of before and after detection data of construction of tamping machine shows that:the level of long-wave and short-wave regularity of the trial region has been greatly improved, which meet th]e requirements of raising speed railway.The engineering practice around the work of this dissertation shows that:the relevant theory, method and technology scheme applied to track irregularity detection and adjustment of raising speed railway have theoretical and engineering application value.

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