抄録
Based on the soil-water coupled finite element analysis incorporated the modified macro-element method, the improvement of soft ground by the vacuum and surcharge preloading method is investigated systematically. SYS Cam-clay model is employed for the constitutive model of soft soils and the soil parameters are determined by the curve fitting of the one-dimensional compression result. The results show that: 1) the settlement at the ground surface is as large as 3.5m which is very close to the design value; 2) the long-term settlement is also predicted and the degree of consolidation at 180d is over 98%; 3) Negative and positive horizontal displacement appears due to the vacuum preloading and surcharge preloading respectively and it is necessary to control the rate of surcharge to avoid the instability of the ground; 4) There is significant oscillation in the pore pressure inside the ground due to the construction of embankment and the following consolidation under vacuum pressure.
