深中通道沉管隧道平面贯通测量方案研究设计

Study and design of plan penetration survey scheme for immersed tube tunnel of Shenzhen-Zhongshan Link

针对深中通道岛隧工程受隧道东端堰筑段施工未预留沉管隧道贯通测量通道影响的情况,通过网形优化设计和理论分析研究,在堰筑段顶板施工封闭前,分阶段采用了“光学投点+GNSS静态”向堰筑段内投射贯通测量基准点并延伸到沉管隧道对接端的方法。经现场实测与精度评估,得出了各阶段点位精度的主要影响因素及对整个隧道贯通带来的误差大小,对隧道施工具有重要指导作用。

In view of the fact that the Shenzhen-Zhongshan Link island and tunnel project is affected by the construction of the weir section at the eastern end of the tunnel without setting the penetration survey passage of the immersed tube tunnel,through the optimization design of the network shape and the theoretical analysis, before the roof construction of the weir section is closed, the method of "optical drop point + GNSS static" is adopted in stages to project the measuring control point in the weir construction section and extend to the butt end of the immersed tunnel. Through field measurement and accuracy evaluation, the main influencing factors of point location precision in each stage and the error of the whole tunnel penetration are obtained, which has important guiding function for tunnel construction.