Method for controlling soil deformation in large rectangular pipe jacking

Abstract

The invention discloses a method for controlling soil deformation in large rectangular pipe jacking. The method comprises the following steps: friction reducing slurry is mixed, and comprises the components of water, bentonite and high-molecular polymers; a slurry injecting port is formed in a pipe piece of a rectangular pipe, and is connected with a slurry injecting pipeline; and in the promoting process of the pipe piece, the friction reducing slurry is injected between the outer surface of the pipe piece and soil through the slurry injecting pipeline to form a layer of mud sleeve on the outer surface of the pipe piece so as to isolate direct contact between the pipe piece and the soil. The soil deformation in the complex-soil layer and large-section rectangular pipe jacking process is controlled through comprehensive methods; firstly, the high-molecular polymers are added in bentonite slurry used for the traditional pipe jacking construction according to a certain proportion, so that the slurry filling viscosity and the pressure bearing capacity are largely improved, and the filter loss in complex soil layers is reduced; and then, the sedimentation is stabilized through soil compensation measures, and even the soil in a settled area is lifted, so that sedimentation parameters satisfy the construction requirements.

Description

technical field [0001] The invention relates to the field of tunnel construction, in particular to a method, a device and an anti-friction grout for controlling the deformation of large-scale rectangular pipe jacking excavation soil. Background technique [0002] Rectangular pipe jacking is a kind of trenchless construction of underground passages, which is very important for urban areas with heavy traffic, population density, numerous ground buildings, complex underground buildings and pipelines. Its construction feature is that it does not affect the traffic on the ground of the crossing section and the pipelines passing through the soil layer, so the deformation of the soil must be strictly controlled during the jacking construction. [0003] The traditional soil deformation control measures are to match the amount of excavation and pressure-inject anti-friction grout (bentonite + water) during the construction process, but it cannot be strictly controlled for complex str...

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Problems solved by technology

[0017] During the construction process, the cutter head will continue to disturb the upper soil. Filling the slurry through the pipe wall has a certain effect. However, the filtration loss and pressure bearing capacity of the bentonite slurry in complex soil layers cannot ensure that the soil settlement deformation is within a controllable range. ; The accuracy of controlling the unearthed amount according to the matching footage will fluctuate greatly after the soil is improved and the soil is not completely dumped.

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