Construction method of secondary direct discharge vacuum preloading treatment of newly dredged silt for land reclamation

Abstract

The invention discloses a construction method of new hydraulic fill muck reclamation by a twice straight-line vacuum prepressing treatment. The treatment of the hydraulic filled soft earth foundation by the vacuum prepressing treatment is no longer limited to the natural drying time after finished the hydraulic fill by layering the new hydraulic fill muck and reinforcing the new hydraulic fill muck step by step, accordingly the reclamation construction period is effectively shortened. In the vacuum prepressing process, a shallow layer drainage pretreatment and a deep layer vacuum prepressing are sequentially acted on the new hydraulic fill muck layer having a high water content, a poor soil property and a low foundation bearing capacity twice, accordingly achieving the optimal integration of the investment and ensuring the treatment quality of the muck foundation. Meanwhile, the working layer is constructed by utilizing the shallow layer pretreatment in combination with the hydraulic fill silt, thus the mechanization level and the efficiency of the deep layer vacuum prepressing are greatly increased, the working surface is more stable, the on-site construction environment is more tidy and clean, and the construction process is more smooth and orderly.

Description

technical field [0001] The invention relates to the technical field of soil drainage and consolidation, in particular to a construction method for secondary direct discharge vacuum preloading treatment of newly dredged silt for land reclamation. Background technique [0002] Vacuum preloading technology is a construction technology widely used in coastal and inland river land reclamation. This technology can treat the dredging mud layer and the bottom undisturbed mud within the design depth to a bearing capacity of not less than 80Kpa in a relatively short period of time. In this way, a land base with high carrying capacity is formed, and the investment in building foundation treatment is greatly reduced. [0003] The general treatment process is to build a construction working layer by laying geotextiles, thorns, plain soil, etc. on the soft soil foundation; lay a medium-coarse sand cushion on it to build a horizontal drainage layer; lay plastic drainage boards; Arrange ca...

AI Technical Summary

Problems solved by technology

However, due to the extremely high moisture content of the newly dredged silt soil, reaching more than 100%, and the ultrafine particles rich in soil particles are suspended in the water, if the conventional vacuum preloading construction is carried out, the unstable ultrafine particles in the soil will Under the action of seepage force, the particles converge towards the plastic drainage board and adhere to the surface of the drainage board, finally forming a mud film with a small permeability coefficient, which blocks the transmission of vacuum negative pressure and prevents the water in the soil from seeping to the drainage board, resulting in drainage Plate failure, resulting in the mud layer treatment can not meet the use requirements

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