Based on the practice of high-grade highway tunnel GPS survey, establishment and data processing method for independent coordinate system of tunnel GPS control network are introduced in the paper.

本文根据生产实践，介绍了高等级公路隧道GPS控制网的建立及用于施工坐标系的数据处理方法。

youdao

There are a great many of tunnels in high-grade highway, it is necessary to adopt the small clear distance tunnel.

小净距隧道的主要特点是比分离式隧道占地少，比连拱式隧道造价低，造型美观；但施工难度大，技术含量高。

youdao