长大隧道洞内平面控制网型研究

Study on the Type of Horizontal Control Network in Long Tunnel

我国铁路、公路、市政、水利等工程长大隧道越来越多,使用的测量仪器和技术也越来越先进,但有些长大隧道贯通精度不高,甚至贯通偏差过大,侵入限界从而导致改线或返工,影响工程质量且浪费巨大.为保证隧道准确贯通,针对隧道洞内施工导线测量方法和网型进行深入研究,并对多条隧道洞内导线测量实测数据进行对比验证.研究及实践结果表明,隧道掘进阶段洞内控制导线不宜采用自由测站边角交会方式,而隧道贯通后洞内CPⅡ导线可以采用自由测站边角交会方式,最后提出了最佳的导线网型进行隧道洞内控制测量.

There are more and more long tunnels in China’s railway,highway,municipal and water conservancy projects.The more and more advanced measuring equipment and technologies are used.However,some of long tunnels are not high in connection accuracy,and some of them have too large a through error,which leads to the invasion of the boundary line to carry out line change or rework,affecting the quality of the project and causing huge waste.In order to ensure accurately penetrating through of the tunnel,a study was done on the survey method and network type of the construction traverse in the tunnel.By comparing and verifying the measured data of the traverse survey in multiple tunnels,it is concluded that the control traverse in the tunnel during the excavation should not adopt the free station side angle intersection mode,and the CPⅡ traverse after tunnel through can adopt the free station side angle intersection mode.In this paper,the optimal traverse network type is proposed for control survey in tunnel.