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CN-122012106-A - Method for improving erosion resistance of low-clay-content dispersible loess

CN122012106ACN 122012106 ACN122012106 ACN 122012106ACN-122012106-A

Abstract

The invention discloses a method for improving erosion resistance of low-clay-content dispersible loess, which relates to the field of hydraulic geotechnical engineering and comprises the following steps of S01 pretreatment of materials, selecting low-clay-content dispersible loess, polyvinyl alcohol powder and aluminum sulfate powder according to mass proportion, respectively drying for standby, S02 uniformly mixing the materials in the S01 in a mixing container, S03 stirring the mixture in the S02 by spraying water for several times, S04 treating the stirred mixture in the S03 with a smoldering material to obtain improved soil, wherein the method for improving erosion resistance of the low-clay-content dispersible loess has good erosion resistance, and greatly improves the dispersibility and erosion resistance of the low-clay-content dispersible loess, thereby reducing engineering harm caused by the low-clay-content dispersible loess serving as a filler.

Inventors

  • YU JINGQIN
  • ZHANG GANG
  • GAO SHANG
  • Mu yanyang

Assignees

  • 宁夏大学新华学院

Dates

Publication Date
20260512
Application Date
20260128

Claims (9)

  1. 1. A method for improving the erosion resistance of low-clay-content dispersible loess, comprising the steps of: S01, preprocessing the material, selecting low-clay content dispersible loess, polyvinyl alcohol powder and aluminum sulfate powder according to mass proportion, and respectively drying for later use; s02, uniformly mixing the materials in the step S01 in a mixing container; s03, spraying water and stirring the mixture in the step S02 for multiple times; S04, carrying out smoldering treatment on the stirring mixture in the step S03 to obtain the improved soil.
  2. 2. The method of claim 1, wherein the loess in step S01 is a low-clay content dispersed soil having a clay content of less than 18%.
  3. 3. The method for improving the erosion resistance of low-clay-content dispersible loess according to claim 1, wherein the mixing amount of the polyvinyl alcohol powder is 0.25% -0.50% of the total mass of loess, and the mixing amount of the aluminum sulfate powder is 5% -10% of the mass of polyvinyl alcohol.
  4. 4. The method for improving the erosion resistance of low-clay-content dispersible loess according to claim 1, wherein the polyvinyl alcohol powder has an alcoholysis degree of 97% or more and a polymerization degree of 1700% or more.
  5. 5. The method for improving the erosion resistance of low-clay-content dispersible loess according to claim 1, wherein the passing rate of a #40 mesh screen of the aluminum sulfate powder is not less than 95%.
  6. 6. The method of claim 1, wherein the mixing time in step S02 is not less than 15min.
  7. 7. The method for improving the erosion resistance of low-clay-content dispersible loess according to claim 1, wherein the water leaching amount in step S03 is controlled according to the optimal water content of loess.
  8. 8. The method for improving erosion resistance of low-clay-content dispersible loess according to claim 1, wherein the treatment of the smoldering material in step S04 is sealing and standing for 24 hours or more at normal temperature.
  9. 9. A low-clay-content, dispersability-improving soil prepared by the method of any one of claims 1 to 8.

Description

Method for improving erosion resistance of low-clay-content dispersible loess Technical Field The invention relates to a hydraulic geotechnical engineering technology, in particular to a method for improving low-clay-content dispersible loess erosion resistance. Background The low-clay content dispersible loess is widely distributed in northwest regions of China, has low clay content (generally < 18%), low liquid limit water content (< 30%), and plasticity index greater than 11, and belongs to low liquid limit clay. The loess has weak cementing effect among soil particles after meeting water, and is easy to cause phenomena of dispersion, turbidity, disintegration, collapse and the like, thereby causing engineering problems of reduced bearing capacity of a foundation, settlement, cracking and the like of a building. At present, the improvement research on the dispersible loess is focused on the aspects of mechanical strength, permeability and the like, but the system improvement method special for erosion resistance (seepage erosion resistance and water flow scouring resistance) is less. The polyvinyl alcohol as a water-soluble polymer has good cohesiveness and environmental protection, can be used for soil improvement, and the aluminum sulfate has the functions of crosslinking reinforcement and pore filling, and can enhance the water stability of soil. The invention combines the advantages of the two, and provides a method for improving the erosion resistance of low-clay-content dispersible loess. Disclosure of Invention The invention aims to provide an improved method for improving erosion resistance of low-clay-content dispersed loess, which systematically improves the erosion resistance of seepage and water flow scouring of the low-clay-content dispersed loess through bonding enhancement and pore filling. In order to achieve the above purpose, the invention provides a technical scheme that the method for improving the erosion resistance of low-clay-content dispersible loess comprises the following steps: S01, preprocessing the material, selecting low-clay content dispersible loess, polyvinyl alcohol powder and aluminum sulfate powder according to mass proportion, and respectively drying for later use; s02, uniformly mixing the materials in the step S01 in a mixing container; s03, spraying water and stirring the mixture in the step S02 for multiple times; S04, carrying out smoldering treatment on the stirring mixture in the step S03 to obtain the improved soil. Further, the loess in step S01 is a dispersive soil having a clay content of less than 18%. Further, the mixing amount of the polyvinyl alcohol powder is 0.25-0.50% of the total mass of loess, and the mixing amount of the aluminum sulfate powder is 5-10% of the mass of the polyvinyl alcohol. Further, the alcoholysis degree of the polyvinyl alcohol powder is more than or equal to 97%, and the polymerization degree is more than or equal to 1700. Further, the passing rate of the #40 mesh screen of the aluminum sulfate powder is more than or equal to 95%. Further, the mixing time in step S02 is not less than 15min. Further, the water spraying amount in step S03 is controlled according to the loess optimal water content. Further, in step S04, the mixture is subjected to a sealing and standing for 24 hours or more at room temperature. The low-clay-content dispersible modified soil prepared by the method. The pinhole test shows that the loess with low clay content is high-dispersion soil (the pinhole test is classified as D1), the loess is subjected to the erosion resistance test, the critical shear stress of the soil sample is 1.05Pa, the erosion resistance index I is 1.86, the extremely low erosion resistance does not meet the engineering construction requirement, and treatment measures are required to be carried out on the dispersion loess until the engineering requirement is met. Through indoor physical property tests, the polyvinyl alcohol can improve the extremely low erosion resistance of the low-clay-content dispersible loess, and the aluminum sulfate powder can improve the crosslinking strengthening effect of agglomerates formed by the polyvinyl alcohol, fill pores and improve the erosion resistance of the dispersible loess. Greatly reduces the harm of low-clay content dispersible loess, is low-carbon and environment-friendly, and saves cost. Compared with the prior art, the method for improving the erosion resistance of the low-clay-content dispersible loess has the following beneficial effects: (1) The improved low-clay-content dispersible loess has good erosion resistance, and greatly improves the dispersibility and erosion resistance of the low-clay-content dispersible loess, so that engineering harm caused by taking the low-clay-content dispersible loess as a filler is reduced. (2) The polyvinyl alcohol content adopted by the invention is lower than 0.50%, the soil microorganism is not damaged, and the mulching film can be degraded, so that