Shield burial method for receiving and plugging overexcavation gap in high-water-pressure stratum

Abstract

The invention belongs to the technical field of waterproofing plugging of tunneling overexcavation gaps, and particularly relates to a shield burial method for receiving and plugging an overexcavation gap in high-water-pressure stratum. The invention solves the problem that the existing overexcavation gap waterproofing plugging technique is not suitable for high-water-pressure stratum, has high risk for shield receiving and can easily induce accidents. The method comprises the following steps: preserving a shield receiving well; breaking the wall of the shield receiving well to chisel out an annular groove, and laying freezing pipes in the annular groove; filling water into the shield receiving well, or filling water after filling soil; impelling the shield machine until only the shell of the shield tail is still in the entrance / exit ring of the tunnel; starting freezing, and injecting grout into the overexcavation gap; pumping water when the shield receiving well is isolated from the outside confined aquifer; and after pumping water to remove silt, cutting off part of the shield tail, and lifting out the disassembled shield machine, thereby completing receiving. The invention has the beneficial effects of ensuring that the shield can be received in the high-pressure fine sand layers and other severe strata, and preventing catastrophic accidents in shield receiving in unfavorable strata.

Description

technical field [0001] The invention belongs to the technical field of water-proof and leak-proof plugging of overcut gaps behind segment walls when shield tunnels are received in a shield tunnel construction project, and in particular relates to a method for shield tunnel submerged receiving and plugging over-cut gaps in high water pressure formations. Background technique [0002] The existing waterproof and plugging technologies for over-excavating gaps behind the segment wall during shield receiving mainly include: [0003] ①Pressure-injection double-fluid cement mortar waterproof plugging technology. This is a commonly used method of waterproofing and plugging when receiving shield tunneling, that is, before breaking the door when receiving shield tunneling, use cement slurry and a certain proportion of water glass to inject it into the over-excavated gaps behind the segments and shield walls. In order to prevent groundwater, especially groundwater with a certain press...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem that the existing shield receiving wall thickness over-excavation gap waterproof plugging technology is not suitable for high water pressure formations, resulting in high risk of shield receiving and accident-prone problems, the invention provides a shield tunneling buried in high water pressure formations Method of receiving and plugging over-excavation gap

Images