Reinforcing method for underneath passing of existing pipeline in ultra-shallow-buried underground excavated tunnel by utilizing municipal well

Abstract

The invention relates to a reinforcing method for underneath passing of an existing pipeline in an ultra-shallow-buried underground excavated tunnel by using a municipal well, and belongs to the technical field of tunnel construction. The reinforcing method comprises the following steps that the range of a grouting reinforcing area is determined; a grouting reinforcement scheme is determined; a plurality of settlement observation points are arranged for real-time monitoring; when excavation is carried out to a first preset position where an existing pipeline penetrates downwards, advance supporting of a pipe shed and a small guide pipe is stopped in an arch crown area; a municipal road well communicating with the existing pipeline is utilized, and drilling grouting reinforcement is carriedout on surrounding rock-soil bodies according to a pre-divided grouting reinforcement area; after grouting is completed, excavation construction of underneath passing of the tunnel through the existing pipeline is carried out; temporary vertical supports are applied to reinforce supporting; when the underground excavated tunnel is excavated to penetrate through a second preset position on the other side of the existing pipeline, advance supporting of the pipe shed and the small guide pipe is continued; and an original municipal road well is repaired. Normal use of theexisting pipeline and construction safety of a newly-built tunnel can be guaranteed, and the purpose of controlling settlement deformation of the existing pipeline and the ground is achieved.

Description

technical field [0001] The invention belongs to the technical field of tunnel construction, and relates to a reinforcement method for ultra-shallow buried tunnels passing through existing pipelines under municipal wells. Background technique [0002] With the continuous expansion of urban scale, underground roads and rail transit have become the key construction targets of urban space development. The excavation of tunnels often passes through areas with dense underground pipe networks, where there are municipal road wells such as drainage wells and various inspection wells. When the ultra-shallow buried tunnel passes through the existing pipeline, the unloading effect caused by the close construction will lead to the stress redistribution of the rock and soil around the tunnel, induce the settlement and deformation of the ground, and affect the normal use of the existing pipeline, and even crack and leak. series of questions. When constructing ultra-shallow buried tunnels...

AI Technical Summary

Problems solved by technology

However, these three reinforcement methods also have certain applicable conditions. For example, there must be a sufficient distance between the ultra-shallow buried tunnel and the existing pipeline for pipe shed and advanced small conduit support, and the ground road above the tunnel interrupts traffic or has The construction environment for drilling is reinforced by grouting, and the upper rock and soil mass of the ultra-shallow buried tunnel is mostly filled with soil, and the temporary support of the tunnel alone cannot ensure the safety and normal use of the existing pipelines

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