Layout Technology of 'One Network to the Bottom'Control Network for High-Speed Railway Tunnel Group
The pace of national high-speed railway construction continues to advance,and tunnel group projects are gradually increasing.If the breakthrough error exceeds the limit,it will cause problems such as insufficient tunnel boundaries and insufficient lining thickness,leading to hidden dangers in the quality of the tunnel structure and causing huge economic losses.Usually,a point by direction(i.e.fixed point,fixed azimuth)adjustment method is used to establish an independent coordinate system different from the design measurement benchmark.This method can enhance the integrity of the tunnel and improve the accuracy of the connection,but errors will accumulate to the end of the direction,resulting in lateral deviation(angle)and chain breakage(mileage)problems,affecting construction and adjacent overlap.In order to avoid accumulated errors and ensure the accuracy of penetration,this article takes a tunnel group project as an example to study and analyze the location and direction of the line,and adopts the'one network to the bottom'adjustment method(that is,without changing the design measurement benchmark)to establish a tunnel construction control network.After comparing the adjustment results data,comparing the measured edge length and angle,and estimating the connection error,the applicability of the'one network to the bottom'adjustment is verified.
lateral deviationtunnel groupdesign benchmarkone network to the bottom
NETL
NSTL
万方数据
