Method for solidifying and processing soft soil foundation by draining water from plant cushion layer in vacuum

Abstract

The invention relates to a method for solidifying and processing soft soil foundation by draining water from a plant cushion layer in vacuum. The method comprises the following steps of: 1) crosswise placing and flattening a hollow plant; 2) inserting vertical draining plates and exposing the top ends of the draining plates; 3) paving a main tube and an integrated draining plate layer horizontally; 4) digging peripheral sealed ditches around, paving geotextile layers on the main tube and the integrated draining plate layer sequentially, and paving vacuum films on the geotextile layers; 5) starting vacuum equipment, running the vacuum equipment at low pressure and trying to vacuumize; 6) controlling a vacuum degree exertion speed, increasing the vacuum degree day by day from 20kPa at a speed of 2 to 5kPa per day until the vacuum degree is more than 85kPa and stabilizing the pressure; 7) covering water on the films during pressure stabilization; 8) monitoring parameters during vacuum exertion, finding out problems and correcting the problems timely; 9) drawing a sedimentation-time curve and a vacuum-degree-time curve; and 10) removing the vacuum equipment after the sedimentation-time curve is stabilized. Compared with the prior art, the method has the advantages of low cost, good effect and the like.

Description

technical field [0001] The invention relates to a method for treating soft ground in geotechnical engineering, in particular to a method for treating soft ground with vacuum drainage and consolidation of plant cushions. Background technique [0002] The application of soft soil foundation treatment has broad prospects. Due to the gradual economic development and relatively high population density in the eastern coastal areas, the available land resources in cities are gradually decreasing, and land reclamation projects are increasing day by day, such as Qingdao Haixi Bay Beihai Shipyard, Shenzhen Airport Expansion, Shanghai Nanhui District Lingang New City, Tianjin Lingang Industrial Zone, Wenzhou Peninsula Project, etc., and with the development of the city, there is a trend of increasing land reclamation projects. After land reclamation, a large amount of soft soil foundation is formed, which has the characteristics of flow, large deformation, high water content, high comp...

AI Technical Summary

Problems solved by technology

In the past, due to the lack of land resources, the interval between reclamation and land reclamation to normal use was generally relatively long, maybe 5 or 6 years, and sometimes 8 or 9 years. However, some sites will be used in 1, 2 years, or even immediately after land reclamation. Obviously, this method can no longer meet the short-term land use needs, so it needs For foundation treatment, the treatment methods for soil with high clay content generally include vacuum preloading, surcharge preloading, vacuum surcharge combined preloading, etc. Due to the limitation of the source of surcharged materials and the conditions for aftermath, the vacuum preloading method is more widely used. many

However, due to less and less sand sources and higher prices, for example, the sand used in the Shanghai area is generally purchased from Jiangsu and other places, and the distribution of sand in the coastal area is gradually decreasing, and it must be obtained from the farther river bottom and seabed. The sand cushion has gradually become a limiting condition for the promotion and application of vacuum preloading. It is very urgent to find a new drainage cushion with good effect, low cost and environmental protection.

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