Soil improving method for rectangular-pipe jacking construction in gravel soil layer

Abstract

The invention relates to a soil improving method for rectangular-pipe jacking construction in a gravel soil layer. The soil improving method specially includes that a PAM (polyacrylamide) solution and a bentonite mud solution are added to a working surface and the soil body of a soil pressure bin, content of the PAM in the PAM solution ranges from 1g / L to 4g / L, and the mass concentration of the bentonite mud solution ranges from 7% to 11%. The soil body cut with the soil improving method is improved to have the advantages of good fluidity, low frictional angle, middle compressibility, lower adhesivity, low permeability and the like, the full-tank jacking and jacking construction speed are ensured, problems about uneasiness in soil pressure balance construction, severe abrasion of a nose cutter, easiness in 'caking', proneness to 'water gushing' when the nose cutter passes through the water-baring layer and the like can be solved, requirements of the rectangular-pipe jacking construction with the soil pressure balance can be met, and technical support is provided for establishment of dynamic soil pressure balance of the soil-pressure-balance rectangular-pipe jacking working surface of a multicutter in the gravel soil layer.

Description

technical field [0001] The invention relates to the field of underground non-excavation technology, in particular to the construction technology of single cutterhead or multi-cutterhead earth pressure balance rectangular pipe jacking technology, and in particular to a soil improvement method for rectangular pipe jacking construction in gravel soil stratum. Background technique [0002] In recent years, the rectangular earth pressure balance pipe jacking method has been gradually applied to the construction of urban pedestrian underpasses. Using this kind of underground trenchless technology to build underground passages has the advantages of high cross-sectional area utilization rate, shallow buried depth, uninterrupted ground road traffic, avoiding the demolition of various underground pipelines, no noise, and no environmental pollution. It represents the future urban underground The development direction of pedestrian crossing construction technology. At the beginning, th...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a soil improvement method for rectangular pipe jacking construction in gravel soil stratum, which improves the soil to have good fluidity, low friction angle, medium compressibility, low adhesion and low permeability It can ensure full tank jacking and reasonable jacking construction speed, and can solve problems such as poor establishment of earth pressure balance, serious wear of the nose tool, easy "cake formation", and "water inrush" when crossing the aquifer. To meet the needs of earth pressure balance rectangular pipe jacking construction, and provide technical support for the establishment of earth pressure dynamic balance of multi-cutter earth pressure balance rectangular pipe jacking face in gravel soil stratum

Images