A method for changing the arch using a mobile arch changing device for the primary support section of the tunnel

Abstract

A method for changing an arch using a mobile arch changing device for the primary support of the tunnel intrusion section, the device includes an annular reaction force frame and two mobile frames, both of the two mobile frames are extended and placed along the tunnel's traveling direction, and the annular reaction force frame The two ends of the tunnel are respectively installed on two mobile frames, and the outer peripheral surface of the annular reaction force frame is provided with a plurality of jacks for crimping on the steel arch frame supported inside the tunnel; among them, the annular reaction force frame is a plurality of jacks. , two adjacent ring-shaped reaction frames are connected to each other through longitudinal connecting rods, and the jacks on the same ring-shaped reaction frame correspond to the steel arches supporting the same frame inside the tunnel. The arch replacement method of the device realizes demolition-rework alternately until the arch replacement construction of the entire arch frame is completed. The construction efficiency is high, and the tunnel arch replacement support operation can be completed conveniently and quickly, and safe construction can be provided for the tunnel arch replacement. working environment.

Description

technical field [0001] The invention relates to the field of tunnel engineering construction, in particular to a method for changing an arch by using a mobile arch-replacing device for the primary support of the invasion section of the tunnel. Background technique [0002] At present, the new Austrian method is generally used in tunnel engineering construction, that is, after the tunnel is excavated, the bearing capacity of the surrounding rock itself is fully utilized, the deformation of the surrounding rock is limited by the primary support and the force is shared with the surrounding rock, and the secondary support is applied after the deformation of the surrounding rock is stable. The secondary lining acts as a strength reserve. After the initial support on the steel arch frame of the tunnel, due to poor geological conditions, bias pressure, groundwater, and inadequate construction organization, etc., it is easy to cause excessive deformation of the vault and side walls ...

AI Technical Summary

Problems solved by technology

[0003] It should be pointed out that the current "arch replacement" method has problems such as complicated construction procedures and prominent safety hazards in terms of intrusion support, demolition and grouting.

For example, in the case of intrusion support, plates, columns, beams, etc. are often used to set up support platforms in the tunnel arch change area to reinforce the primary support in the arch change area. However, the node connections of the old and new rigid frames are weak, and the Poor strength may easily lead to insufficient support strength and affect support safety

When the arch frame is demolished, impact drills or breaking hammers are mostly used to destroy the initial concrete. The lack of support protection for the demolition arch will easily lead to concrete collapse and arch collapse, endangering the safety of construction personnel.

Grouting reinforcement is an effective measure to improve the stability of the surrounding rock, but in many projects, the grouting consolidation is ineffective and even softens the surrounding rock, which is very dangerous when changing the arch of the tunnel

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