Method for treating peat soil foundation through preloading in combination with salt piles

Abstract

The invention discloses a method for treating a peat soil foundation through preloading in combination with salt piles. The method for treating the peat soil foundation through preloading in combination with the salt piles is characterized in that the multiple salt piles with coarse sea salt as a core material are driven into the peat soil foundation; a horizontal drainage sand cushion is laid on the surface of the peat soil foundation; and a pre-load layer is constructed on the horizontal sand cushion layer. According to the method for treating the peat soil foundation through preloading in combination with the salt piles, through the ionizing effect of sodium chloride in the salt piles, pore water in the peat soil is driven to move towards the sodium chloride, a high-icon-concentration water film is formed on the surfaces of crystals in the dissolution process of the crystals, the electrostatic potential and the concentration potential generated around the water film can attract contra-ions in micropore water, so that the seepage speed of the micropore water into macropores is increased, and therefore the deformation rate of the peat soil in the whole drainage consolidation process is increased; and in addition, the salt piles driven into the peat soil foundation are similar like sand drains and can provide drainage channels for seeping out of a large amount of pore water in the peat soil layer in the preloading process, and therefore the efficiency of preloading treatment of the peat soil foundation is improved.

Description

technical field [0001] The invention relates to the technical field of foundation treatment, and specifically discloses a method for treating peat soil foundations by using heap preloading combined with salt piles. Background technique [0002] Peat soil (collectively referred to as peat and peat soil) is a special kind of humus soil, which is accumulated by oxidation and partial decomposition of plant remains in the surface swamp environment with high void ratio, high water content, and high water permeability. , High organic matter, special soil formed within 10,000 years. According to statistics, peat soil is distributed in 59 countries and regions around the world, with a total area of ​​4.153 million km 2 above; the distribution area in my country is about 42,000 km 2 , mainly distributed in the Changbai Mountains, the Greater and Lesser Khingan Mountains, the Sanjiang Plain, most mountainous areas in Xinjiang, the Ruoergai Plateau in western Sichuan, the Qinghai-Tibe...

AI Technical Summary

Problems solved by technology

Existing engineering practice shows that the peat soil foundation will undergo significant settlement deformation under load, especially the post-construction settlement caused by the next consolidation deformation under long-term load is serious

Several foundation treatment methods commonly used in engineering can not solve the problem of large primary and secondary consolidation settlement of peat soil foundation:

[0005] (1) Due to the high initial permeability coefficient of peat soil and the obvious secondary consolidation phenomenon, the most commonly used (overload) preloading method combined with vertical drainage boards has no obvious effect;

[0006] (2) In the chemical treatment method, the amount of additives such as cement and lime is relatively large, resulting in high project cost and poor economy;

[0007] (3) Vacuum preloading drainage consolidation method has problems such as easy blockage of vacuum tubes, difficulty in transportation and installation of vacuum pumping devices, etc.

[0009] (1) The initial permeability coefficient of peat soil is relatively large, and the effect of the drainage board on accelerating pore water seepage is not obvious;

[0010] (2) There is a large amount of bound water in the micropores of peat soil that is not easy to discharge, and the secondary consolidation deformation under load is significant, and the effect of surcharge preloading on accelerating the secondary consolidation deformation rate is not obvious

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