长大隧道控制测量横向贯通误差精度研究

Research on the Accuracy of Transverse Penetration Error in Long Tunnel Control Measurement

长大隧道平面控制测量横向贯通误差是隧道洞内控制测量的重点,为保证控制测量精度,必须依据规范提前对隧道控制网进行精度分析。隧道平面控制测量横向贯通误差大小主要由洞外控制网和洞内控制网的误差决定。工程施工前,设计院均进行设计交桩,对设计控制点进行复测后,如设计点成果精度满足隧道控制网精度等级要求,即可根据设计成果进行洞外控制网加密,继而根据控制网精度进行隧道横向贯通误差精度分析。本文以涪秀二线新郁山隧道为例,通过将洞内、外控制网的误差按三种导线测量精度等级要求分别进行预先估算,计算出各等级精度下的误差大小,以便对隧道施工过程中洞内控制测量进行指导。

Transverse penetration error of plane control measurement in long tunnel is the key point of control measurement in tunnel.In order to ensure the accuracy of control measurement,the precision analysis of tunnel control network must be carried out in advance according to the requirements of the specification.The transverse penetration error of tunnel plane control measurement is mainly determined by the errors of control network outside and inside the tunnel.Before construction,the design institute has carried on the design of pile,after retesting the design control points,if design point precision can meet the requirements of tunnel control network precision grade,and can be based on the results of design for hole control network encryption,the control points in the hole will be encrypted in a way that you can according to the precision of control network for tunnel of lateral breakthrough error precision analysis.In this paper,Xinyushan Tunnel of Fuxiu second-line is taken as an example,the errors of the control network inside and outside the tunnel are estimated in advance according to three kinds of precision grades,and the errors under each grade of precision are calculated,so as to guide the control survey in the tunnel construction process.