Study On Effect Of Plastic Drain Board Method Reinforce Super Soft Foundation

With the development of economy, reclamation projects are adopted by more and more cities, the area is becoming larger. But the fill’s water content is high, permeability coefficient, strength and degree of consolidation are low. To meet the needs of engineering, we usually use vacuum preloading dispose the fill and have meet with success. For Plastic drainage board is convenient for construction. quality is stable. can be mass production. etc. it is usually used as vertical drainage channel of vacuum preloading technology. However its filter fabrics are not unified and the filter fabrics can affect the result of vacuum preloading.To explore the influence of different filter fabrics to vacuum preloading. Designing model test to study three kind filter fabrics with different equivalent aperture. During the model test, making the three filter fabrics into vertical drainage to dispose the soft soil, and monitor the change of vacuum degree, settling volume, water yield and pore water pressure. Analyze the drainage consolidation from area to area of every kind filter fabrics. Before and after the model test, measuring the water yield and vane-shear strength of the soil to estimate the result of vacuum preloading of every filter fabric. After the model test, analyzing the gradation curves of the soil next to the vertical drainage to estimate the soil loss of different area of every test.The research results show: under the vacuum preloading, the result of soft ground treatment is affected by the permeability of filter fabrics and soil pore. The seepage path is shorter, The soil pore and filter fabrics are smoother the effect of vacuum improve soft foundation is better. The filter fabrics with bigger aperture have strong ability to resist siltation so the effect of disposing soft soil is better. The filter fabrics whose fibers are strong can resist mechanical deformation and soft foundation improved well. During the test, the soil next to the vertical drainage channel run away and the aperture is bigger the distance is shorter the greater the loss of soil.