高铁轨道基准网平面网坐标转换方法研究

Track baseline data processing network method for coordinate transformation in high-speed railway

在高速铁路轨道基准网平面网数据处理中,需要将外业所测合格的轨道基准点坐标从测站站心坐标系转换到铁路工程独立坐标系,目前德国采用的是三参数坐标转换模型,而不是常规采用的四参数坐标转换模型。介绍了2种平面坐标转换模型及其转换参数精度评定的算法,通过对2种坐标转换的转换参数精度、坐标转换前后公共点残差以及站间坐标搭接情况的比较分析,认为2种坐标转换方法均能满足轨道基准网的精度要求,但是在其上一级CPⅢ控制网为约束平差的前提下,采用四参数坐标转换方法效果更优。

To process the data of horizontal network of track basis net of the high-speed railway,it is required to rewrite coordinates of qualified track datum mark,which are surveyed in the field operation,from the survey station＇s topocentric coordinate system into the independent coordinate system of railway engineering.At status quo,Germany adopts tri-parameter transformation model rather than the regularly utilized quad-parameter transformation model.In this article,both coordinate systems and the algorithm of assessing the precision of the parameter transformation are introduced.It is suggested that both transformation models could meet with the requirements of precision of track basis net,through the comparative analysis on the transformation parameters＇ precision of both coordinate systems by the residual error of common points before and after the coordinate transformation,and the overlapping situations from various stations.However,it is quad-parameter coordinate transformation that appears to be better,on the assumption that the higher level,i.e.CPIII control network is used as the constrained surveying adjustment.