“移去-恢复法”在机场工程大比例尺测图控制网中的应用

Application of remove-restore method in large-scale topographical mapping control network in airport construction

对大地高、正高与正常高的关系进行阐述,对机场工程场址条件较为困难时使用区域似大地水准面精化的方式满足大比例尺测图的可能性进行叙述,对"移去-恢复法"的计算方法、误差来源与精度评定方法进行论述,在实际算例中使用不同的EGM模型、不同的残差拟合方法所得到的结果进行比对,提出适合于机场工程大比例尺测图用控制网点正常高值拟合的方法。

The paper briefly reviews the relations between ellipsoidical height, normal height and quasl-geoid height, and discusses the possibility of using regional quasi-geoid refining method in large-scale topographical mapping during the detailed-investigation stage of airport construction. Also the remove-restore computational method, the sources of error, and the ways of occuracy assessment are introduced. In real case studies, the results previously obtained from traditional methods are evaluated and compared against those from EGM model with different resolution and method of error fitting. A new method is proposed for fitting the values of quasi-geoid height on control mesh points, which is appropriate to the large-scale topographical mapping in airport construction.