西藏高原带(线)状工程高程拟合精度分析

Analysis of elevation fitting accuracy of strip(linear)project in Tibet Plateau

在西藏高原地区进行带(线)状工程的高程测量面临比平原地区更为复杂的挑战。为了迅速获得满足工程建设需求的精确高程数据,本文针对某具体工程案例,采用了多项式曲线拟合、最小二乘平面拟合、三次样条曲线拟合和二次曲面拟合等4种单一拟合模型,以及结合重力场模型的“移去-拟合-恢复”法混合模型计算拟合高程,分析评估各种拟合方法的精度。经对比分析,单一模型中三次样条拟合模型在高原地区带(线)状工程高程拟合精度最好,且满足三等水准测量精度要求。本文为类似西藏高原地区工程项目在高程拟合时提供了重要的参考价值。

The elevation measurement of belt(line)projects in the Tibetan Plateau faces more complex challenges than in the plain areas.In order to quickly obtain accurate elevation data that meet the needs of engineering construction,this study uses four single fitting models,such as polynomial curve fitting,least squares plane fitting,cubic spline curve fitting and quadric surface fitting,and combines the gravity field model.The“remove-fit-restore”method calculates the fitting elevation and analyzes and evaluates the accuracy of various fitting methods.Through comparative analysis,the cubic spline fitting model in the single model has the best elevation fitting accuracy in the belt(line)project in the plateau area,and meets the accuracy requirements of the third-class leveling.The findings of this study provide an important reference value for similar projects in the Tibetan Plateau during elevation fitting.