铁路测量中坐标系的建立与转换

在铁路测量中，长度投影变形要求小于2．5cm／km。但是由于铁路为典型的线性工程，通常横跨多个投影带，因此采用国家标准3。带难以满足铁路测量精度要求，本文通过分析高斯投影长度变形，提出分段建立独立坐标系的方法，控制长度投影变形，满足精度要求，最后介绍利用GlobalMapper软件实现两个独立坐标系的转换。

Establishing and Conversation of the Coordinate System in Railway Survey

In the railway survey, the requirement of length projection setting is less than 2.5cm/km. However, the railway is the typi- cal linear engineering and it usually crosses multiple projection zones, so the adoption of the national standard of three dimensional zones can not meet the precision requirements in railway survey. This paper through analyzing the scale error of Gauss projection pro- poses the method of establishing an independent coordinate system in section, controlling the length projection setting, meeting preci- sion requirements, and introducing the use of the software of Global Mapper at last, to realize the conversation of two independent co- ordinate systems.