Retest And Stability Analysis Of CP? Plane Control Network In High-speed Railway

The development of China's high-speed railway has entered a period of comprehensive construction and operation.With its high operating speed,high passenger capacity,low time consumption,good safety,low energy consumption,comfort and convenience,it occupies a dominant position in the fierce passenger market competition.Because of the high speed of high-speed railway trains,the requirements for track smoothness are also higher,and the track smoothness is determined by the geometric position of the track.The CP? control network provides a control basis for track smoothness detection and re-testing.The selected measurement method and the accuracy of the measurement data will have a certain impact on the track smoothness.In order to ensure the safety of the train,the retest of the CP? control network of the high-speed railway is essential.In this paper,the CP? control network measurement method,network layout,accuracy evaluation,data processing process,stability analysis of control points,and CP? real-time coordinate calculation on long continuous beams of high-speed railway are taken as research objects.Analysis,a method for judging and detecting the stability of the CP? control network through the geometric relationship between the horizontal and longitudinal chord lengths of the CP? control points,and the establishment of a real-time correction model of the CP? point coordinates on the continuous beam for the construction of the project Provide better data and security.This article first introduces the basic knowledge of the CP? plane control network,and theoretically expounds the CP? plane control network layout,retesting methods,data processing principles and procedures,and accuracy indicators.The method used for CP? plane control network re-measurement is the free-setting station-corner intersection method.The instrument automatically searches for the target,sights the target,readings and records the original observation data.During the data processing process,the conventional fixed weights are compared and analyzed in detail.The advantages and disadvantages of the method and Helmert variance component estimation fixed weight method.Then,according to the CP? plane control network model,an optimization scheme is proposed for the stability detection of the CP? plane control network.On this basis,a geometric model using horizontal and longitudinal chord lengths between CP? control points is proposed to detect the stability of the CP? control network.The geometric relationship between adjacent control points is determined by the relationship between the horizontal and vertical chord lengths between CP? control points.Then through data processing and calculation,the mid-length error between the two points is obtained,and the stability of the CP? point is judged by comparing the error between the retest and the original measurement,and the chord length difference required by the "High-speed Railway Engineering Measurement Specification" The medium error is used as the judgment standard to judge the reliability of this method,which shows that it is of research significance to use several relationships between adjacent points of the CP? plane control network to detect the stability of CP? points.Finally,by studying the problem of continuous beams due to changes in the external temperature of the beam body at different time periods,the beam body will expand and contract,resulting in corresponding changes in the control points on the continuous beam.The stable mathematical model greatly reduces the workload of repeated measurement on the continuous beam each time the continuous beam is constructed,and improves the efficiency of the continuous beam CP? retest method.