Observation method of crown settlement and periphery convergence of tunnel

Abstract

The invention discloses an observation method of crown settlement and periphery convergence of a tunnel. The observation method comprises the following steps of: forming a new excavated section of the tunnel, then replacing a hanging hook by an ordinary reflective sticker, firmly sticking the ordinary reflective sticker as a measuring point on the wall of the tunnel, and marking in the center position of the sticker; measuring three-dimensional coordinates of the measuring point by using an ordinary engineering 2'' electronic total station through a prismatic-free measurement method, thus fast getting the relative variation of elevation and position according to the three-dimensional coordinate data values measured every time, and further knowing the crown settlement and the peripheral wall rock displacement variation. According to the method disclosed by the invention, the precision and the speed of the crown settlement and the periphery convergence during monitoring and measurement of the tunnel can be effectively improved, accurate data can be provided for construction of the tunnel and the construction can be guided.

Description

technical field [0001] The invention belongs to an improved method for observing tunnel vault settlement and surrounding rock displacement convergence. Background technique [0002] Monitoring and measurement refers to the regular observation and measurement of the deformation and stability of surrounding rock, ground surface and support structure, as well as the dynamics of the surrounding environment during tunnel construction. To understand and master the stability of surrounding rock and the reliability of the supporting structure system to ensure the construction safety and long-term stability of the structure, to change the level of surrounding rock, adjust the parameters of primary support and secondary lining, guide the construction sequence, correct It is an indispensable process to realize information design and construction. Among them, the sinking of the vault and the horizontal convergence are the must-test items, and they are also the most basic and important ...

AI Technical Summary

Problems solved by technology

In the traditional method, both vault settlement and convergence observation need to bury points with hooks to achieve observation. When performing vault settlement observation, because the tunnel is generally about 8 meters clear before the lining, it is difficult to observe with a tape measure Hang it up; in addition, tunnel construction generally encounters more groundwater, which will cause more mud in the tunnel in the early stage, which will affect the accuracy of the turning point of the level, and factors such as deformation of the steel tape, stress, and different hook positions will also affect the observation accuracy.

Also for convergence observation, when the tunnel is excavated by steps, the observation needs to be started when the first step is excavated. After the lower step is dug out, the convergence meter cannot be hung on the measuring point without the help of mechanical equipment. At the same time, because the ruler of the convergence meter is affected by gravity and sagging and the influence of force, the accuracy is not enough to accurately analyze the results of the surrounding rock conditions.

In short, using the traditional buried point and observation method, although high-precision instruments are used, it is very inconvenient and the effect is not very good