| As the coastal city of city scale unceasingly expands, super soft soil foundation treatment problems have increased in several years. Many scholars use all kinds of methods of deep large area of soft soil foundation for the researches about various geological conditions, such as ultra-soft soil consolidation effect. Because the relevant studies about reclaimed soil forming deep geological condition of soft soil drainage consolidation is less, it’s important to explore the deep drainage system in the super soft soil layer on the consolidation effect of impact force. According to the theory about the static and dynamic drainage consolidation of soft soil foundation reinforcement mechanism (the national natural science fund, project approval no (51178122), and focusing on similar situation on a port of ZhanJiang buried super soft soil geology, the purpose of this paper is to explore the impact buried deep under the ultra-soft soil in different drainage systems of soil pressure, pore pressure and settlement of change rule by using 1:30 similar percent model study and the model text about the moisture content of 66.2%, pore ratio 1.77 super soft soil by the Static-Dynamic Drainage Consolidation Method (SDDCM) of indoor.Model test, according to the project can be divided into three kinds of typical partition to 1:30 proportion to simulate, which spread on the soft soil area and the area of 0.9 m thickness of sand cushion, shop again, fill in 4.2 m of clayey soil as the covering soil layer, three areas laid 5.1 m clayey soil as the covering soil layer; Vertical row of water body in three kinds of typical partition is triangular way, which area board spacing of 1.2 m, respectively, and layout spacing for 18 m collecting well and blind ditch; Second district board spacing of 1.8 m, respectively arrangement spacing is 18 m collecting well but not blind ditch of layout; Three plate spacing were 1.2 m, and distance of 13.5 m collecting well and blind ditch. Unlike previous laboratory test this simulation model test covering soil thickness (equivalent to 5.1 of the actual project m) than in the past (the original simulation test using maximum covering soil layer thickness of only 1.95 m) more features. This model test has the following several aspects of research:(1) Both vertical and horizontal to set the row of good water permeability and horizontal bedding and vertical row of relatively large area water density consolidation effect is best.(2) In the same set of well spacing and the horizontal drainage cushion layer, but large drain spacing the second area is, above the lower amount of super soft soil pore pressure dissipation and effective stress increment and settlement in about 76.1%,77.2% and 72.2% of the first area respectively, this demonstrates that the density of board and the construction of deep buried super soft soil of blind ditch drainage consolidation, flashboard distance closer, super soft soil consolidation effect is better, and the construction to a certain extent of blind ditch to speed up the pore pressure dissipation, produce subsidence bigger.(3) Horizontal drainage cushion layer permeability lower weaker of third areas, super soft soil above the soil pore pressure dissipation capacity, effective stress increment and subsidence in about 65.2%,65.5% and 64.3% of the first area respectively, and the lower the third area super soft soil above the soil pore pressure dissipation capacity, effective stress increment and settlement about two area were 85.8%,84.8% and 89.1% of the second respectively, drainage cushion tests showed that the osmosis of deep buried super soft soil consolidation effect is very big, the better the permeability and consolidation effect is obvious, more settlement;But by encrypting drain spacing, shorten the collecting well spacing (can shorten the pore water penetration distance), which can effectively make up for the defects of the weak drainage cushion layer permeability.(4) Compared with model test results, this model test found in the covering layers of geological conditions, lamping instant, the pore pressure increases to the peak before rapidly reduced to a certain stress level, the value is improved than before tamping, then increased to a peak, and tends to be stable, that under the covering soil layer and the impact of load combination, in a certain time, pore pressure can maintain in a high stress level.(5) Using Midas (GTS. NX) area this model test and numerical simulation analysis of three, the simulation results with model experiment sedimentation variation has a good consistency, partly verified the model box test the feasibility and the rationality of the simulation field engineering examples.(6) Based on the model test and finite element simulation analysis result shows that when the horizontal drainage cushion poor permeability (10-5 cm/s), deep in the ultra soft soil layer can be set spacing was (1.2 m) of the vertical water, collecting well spacing (20 m to 30 m) are generally reduced 1.3～1.4 times of the drainage system can make the super soft soil has good drainage consolidation effect. |
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