Method for repairing rock stratum shield subway tunnel after accidental breakdown

Abstract

The invention relates to a method for repairing a rock stratum shield subway tunnel after accidental breakdown. The method adopts a mode of combining a dewatering well and a vertical shaft, the vertical shaft is excavated outside a tunnel to a breakdown point, rebars and concrete of tunnel segments are repaired, the repairing effect is good, and the influence on subway operation in the tunnel can be minimized. The inner diameter of the part, in the upper soil layer, of the vertical shaft is larger than that of the part in the lower rock layer, a backfill material is made of foam lightweight concrete, it is guaranteed that the whole backfill material is light, most gravity can be dispersed into the rock layer, the backfill material is prevented from generating too large pressure to the tunnel segments, and therefore the stress safety of the segment structures is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of subway tunnel construction, and in particular relates to a repair method for a subway shield tunnel accidentally broken down. Background technique [0002] The buried depth of urban subway tunnels is generally between 10-30m. During pipeline laying and building construction along the subway line, sometimes the tunnel will be accidentally broken down due to measurement or operation errors, resulting in water penetration accidents in the tunnel. It is necessary to repair the broken down parts as soon as possible. repair. Generally, grouting, water-stopping and steel lining are used for repair in the tunnel, but because the installation of the steel lining requires the temporary removal of pipelines, evacuation platforms, and even catenary supports in the tunnel, it has a great impact on the operation of the subway; moreover, subway tunnels usually The shield method is used for construction, and reinforced ...

AI Technical Summary

Problems solved by technology

Generally, grouting, water-stopping and steel lining are used for repair in the tunnel, but because the installation of the steel lining requires the temporary removal of pipelines, evacuation platforms, and even catenary supports in the tunnel, it has a great impact on the operation of the subway; moreover, subway tunnels usually The shield method is used for construction, and reinforced concrete segments are installed on the inner wall of the tunnel. When they are accidentally broken down, the main steel bars of the segment are often cut off, especially for tunnels in rock formations. Due to the better strength and stability of the stratum itself, the segmental reinforcement The rate is generally low, and the structural strength after being broken down will be greatly affected. There are safety hazards in the simple repair method in the hole, and the maintenance cost in the later period is very high.

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