| With the development of China’s railway industry,especially the construction of high-speed railways has effectively promoted China’s economic development and provided convenience for people’s travel.The construction of high-speed railway is often accompanied by the construction of tunnel engineering.In particular,the long tunnel project is often the key control project of the railway project.Therefore,ensuring the through of tunnel engineering has become an important task of tunnel control measurement.Tunnel control measurement is divided into extra-hole control measurement and in-hole control measurement,out-of-hole control measurement is commonly used GNSS measurement,wire measurement,triangular network measurement and other measurement methods,this paper combined with the actual project Cheng Kun railway tunnel small hunan,discussed the measuring method of plane,elevation control network,network form,matters needing attention,observation data processing and check,adjustment calculation and precision analysis,etc.This paper introduces the tunnel horizontal pass-through error theory in detail,combined with the actual engineering into the Xiaoxiangling tunnel of the Cheng Kun Railway,and discusses the impact of the extra-hole GNSS control measurement and in-hole control measurement elevation control measurement on the through mileage surface.Combined with the actual engineering Xiaoxiangling tunnel,the characteristics of the control conductors in the tunnel,the point laying precautions,the control measurement requirements inside and outside the hole,the data processing and precision analysis of the control wires in the cave are introduced.This paper discusses the application of gyroscopes in the measurement of Xiaoxiangling tunnels,optimizes the optimal position of the control conductors in the tunnel and measures the gyro azimuth,and analyzes the gain effect of the plus-measured gyro-azimusto on the tunnel’s lateral pass-through accuracy.This paper introduces the working principle,characteristics,operation flow and data processing method of 3D laser scanner,briefly describes the operation process of 3D laser scanning technology in tunnel engineering,and discusses the application of 3D laser scanning in tunnel over-excavation detection and earth and stone calculation. |
