摘要
海外铁路项目水准控制点较少,基础资料不齐,普通水准测量方法耗时、耗力,难以满足项目进度需求,故研究一种高效的GNSS高程拟合技术十分必要。首先阐述了GNSS高程拟合的基本原理,并介绍几种常用的拟合算法。利用自主开发高程拟合软件,建立GNSS高程拟合模型,通过计算比较不同高程拟合方法的精度及适用情况,并通过在尼日利亚铁路项目中的实际应用,分析GNSS拟合不同算法与水准测量之间的精度差异及适用情况。研究表明,4种高程拟合方法中,曲面拟合方法精度最优,内符合精度和外符合精度分别为1.05 mm和2.4 mm。拟合的高差与四等水准高差比较,曲面拟合合格率为100%,二次曲线合格率为82%,直线拟合合格率为76%,平面拟合合格率仅为42%;拟合高差与已知点水准点闭合差比较,曲面拟合合格率100%,二次曲线合格率为50%,直线拟合合格率为25%,平面拟合合格率仅为12.5%。研究结果表明,GNSS高程拟合技术在国外铁路应用中具有较高的可行性,能够满足尼日利亚铁路勘测需求。
Foreign projects have few leveling control points and uneven basic data,and ordinary leveling methods have disadvantages of time consuming and energy consuming,which cannot meet the requirements of project schedule.Therefore,it is necessary to study the applicability of GNSS elevation fitting technology in foreign projects.Firstly,the basic principle of GNSS elevation fitting was described,and several commonly used fitting algorithms were introduced.Self-developed elevation fitting software was used to establish the GNSS elevation fitting model,and the accuracy and applicability of the results of different elevation fitting methods were compared by calculation,and the accuracy difference and applicability between different GNSS fitting algorithms and leveling were analyzed by practical application in the Nigeria railway project.The results show that,the surface fitting accuracy of the four elevation fitting methods is the best,and the inner and outer fitting accuracy are 1.05 mm and 2.4 mm respectively.Compared with the height difference of the fourth level,the qualified rate of curved surface fitting is 100%,followed by quadratic curve fitting with 82%,straight line fitting with 76%and plane fitting with the worst qualified rate only 42%.Comparing the fitting height difference with the known water point closure difference,the qualified rate of curved surface fitting is 100%,followed by quadratic curve fitting with 50%,straight line fitting with 25%,and plane fitting with the worst,only 12.5%.The feasibility of GNSS elevation fitting technology in railway application abroad can fully meet the needs of railway survey in Nigeria.
作者
张鹏海
ZHANG Penghai(China Railway Design Corporation,Tianjin 300251,China)
出处
《铁道勘察》
2023年第4期48-52,58,共6页
Railway Investigation and Surveying
基金
中国铁路设计集团有限公司科技研究计划重点课题(2020KF340528)。
