3种平差基准下高速铁路CPⅢ平面控制网的精度分析  

Precision Analysis on High-speed Railway CPⅢHorizontal Control Network under Three Types of Adjustment Datum

作　　者：宋占峰[1] 余世峰 李荣之 李军[1] SONG Zhanfeng;YU Shifeng;LI Rongzhi;LI Jun(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《铁道学报》2024年第10期107-113,共7页Journal of the China Railway Society

基　　金：国家重点研发计划(2021YFB2600403)。

摘　　要：针对工程实际CPⅢ网复测中以CPⅡ进行约束平差出现大量CPⅢ点坐标超限的情况,提出合理的CPⅢ网平差方法,设计总长为4020 m的标准网和加密网两种CPⅢ平面网。建立重心、一点一长方向和一点一短方向3种平差基准,分别计算各基准下两种网形600 m间距CPⅢ点间的相对中误差,并与CPⅡ点相对中误差8 mm的规范规定进行比较。研究结果表明:两种网形在3种基准下,测距精度对点位相对精度影响均非常小,方向精度是影响点位相对精度的主要因素。在重心、一点一长方向(CPⅠ的间距)基准下,两种网形600 m间距CPⅢ点间的相对中误差均显著小于8 mm,高于CPⅡ的相对精度。In response to the situation where many coordinates of CPⅢpoints exceed the limit during constrained adjustment by CPⅡin the remeasurement of CPⅢnetworks,a rational adjustment method was proposed for CPⅢnetworks,with two types of CPⅢplane networks,the standard network and densification network,being designed with a length of 4020 m.Three types of adjustment datum,including gravity datum,one point with one long direction,and one point with one short direction,were established.The relative mean square errors between CPⅢpoints with 600 m spacing were computed for the two types of CPⅢplane networks under the three types of adjustment datum,and compared with the relative mean square error of CPⅡ,8 mm specified by the specification.The study results show that the range accuracy has little impact on the relative precision of points,whereas the direction accuracy plays a major role in affecting the relative precision of points for the two types of CPⅢnetwork under the three types of adjustment datum.The relative mean square errors between CPⅢpoints with 600 m spacing are significantly less than 8 mm for the two types of CPⅢnetwork under the gravity datum and the one point with one long direction(at a spacing of CPⅠ),indicating a higher precision of CPⅢnetwork than that of the CPⅡnetwork.

关 键 词：高速铁路 CPⅢ平面网 平差基准 精度 相对中误差 

分 类 号：U212.24[交通运输工程—道路与铁道工程]