A kind of anti-seepage treatment method for weakly permeable formation

Abstract

The invention discloses an anti-seepage treatment method for a weakly permeable stratum. Curtain grouting is carried out on the weakly permeable stratum, and the construction is divided into two sequences. The first sequence hole is constructed by pulse injection of plastic grout, and the second sequence hole is constructed by using silica sol penetration and solidification. construction. The pore volume in the sand layer is greatly reduced by the low-cost pulse injection plastic slurry process; then, the porosity is further reduced by injecting silica sol nano-slurry with better permeability to meet the requirements of low water permeability. The combination of the two processes not only ensures the quality of the project, but also reduces the cost of the project. It is very effective in preventing seepage in the weakly permeable formation with a permeability coefficient of less than 30 Lu. It can make the permeability coefficient of the formation less than 3 Lu and meet the high standard anti-seepage requirements.

Description

technical field [0001] The invention belongs to the field of anti-seepage engineering, in particular to an anti-seepage treatment method for weakly permeable formations. Background technique [0002] For weakly permeable sand-bearing formations such as sand, silty sand, fully weathered granite, and strongly weathered granite, the pores are small, the water permeability is weak, the porosity is large, and the deformation is large, which makes anti-seepage treatment difficult, especially in anti-seepage. When the requirements for seepage standards are higher, the anti-seepage construction is more difficult. Common anti-seepage methods include grouting, anti-seepage wall, high-spraying and so on. [0003] At present, cement, water glass and polymer organic materials are generally used for grouting treatment, among which cement is the most commonly used grouting reinforcement material. According to the principle that the width of cracks or pores should be more than 3 times the...

AI Technical Summary

Problems solved by technology

Among them, the anti-seepage wall construction technology can solve the anti-seepage treatment of most weakly permeable strata, but for some construction strata with inconvenient sites and large treatment depths, the current anti-seepage treatment methods are not fast enough and economical, especially the anti-seepage treatment effect limited

The chemical grout grouting process usually uses epoxy resin grout, acrylate and other chemical grout for grouting, but due to the high cost of grout materials and high project cost, it is not suitable for promotion

Although the high-pressure pulsating grouting process can reduce the water permeability of the sand layer to a certain extent, it is difficult to achieve the design requirement of less than 5 Lu due to the limited compressibility of the sand layer.

The current silica sol grouting process mostly uses inorganic salt-cured silica sol for grouting, but the sand-containing impermeable formation has a large deformation, and inorganic salt-cured silica sol is used as a grouting material with large shrinkage. Shrinkage, with the deformation of embankment foundation, secondary water leakage is prone to occur, and the anti-seepage durability is poor

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