The Feasibility Study On Treating Soft Soil Foundation With The Super Light Material Pile Composite Foundation

In the treatments of soft soil foundation, rigid pile composite foundation with the too large deadwight and rigidity always can not play a role in dealing with the foundation because of the punching failure or even falling into the soft foundation during the construction; non-uniform type flexible pile composite foundation often occurs the swelling failure because of the soil between piles can not provide enough pressure; drainage treatments need adequate construction period; replacement methods generally only aim at shallow soft soil, and so on. According to the demond of soft soil foundation treatments and avoiding the lack of existing soft soil foundation treatments, this paper puts forward the new method that using super light material as the vertical reinforcement of composite foundation to dealing with soft soil foundation.Using the finite element analysis software (MARC) to calculate the basic parameters of super light material pile composite foundation in the assumed condition. According the material parameters to select the feasible materials,and the preferred material is foamed polystyrene (EPS). EPS using its unique physical to decrease the additional stress of soil and provide buoyancy to avoid the deficiencies of common materials pile composite foundation in dealing with the soft soil foundation. By finite element comparative analysis found that, when the composite foundation of common materials and super light material to achieve the same treatment effect in soft roadbed, the former need to set up a longer length, the latter on this point is better than the former;Through the centrifugal model test, form a systematic research on the deformation and failure mode of EPS pile composite foundation, meanwhile the settlement deformations of soft soil foundation without treatment and EPS pile composite foundation were comparative analyzed, EPS pile composite foundation shows its advantages in dealing with soft foundation again for its gently surface settlement and good working conditions. Analysis of the results showed that use of super light material pile composite foundation to deal with the soft soil foundation is feasible.