Geogrid-reinforced and pile-supported expressway embankment has been widely applied to soft ground improvement; but its bearing and deformation mechanism has not been deeply understood. Combining with the Fourth Yangtze River Bridge’s north-line soft ground reinforced project in Nanjing

the numerical method is used to analyze the variations of settlement and stress of pile and soil

pile axial force and excess pore water stress. The results show that road embankment load is mainly borne by piles as a result of the soil arching effect. The soil pressures of pile and soil increase with the development of embankment load firstly; and then the pressure of pile continue to increase while the pressure of soil decreases in the consolidation process of soft soil. The pile axial force increases quickly during the process of filling. Negative skin friction develops along most part of X-section cast-in-place pile shaft; and the neutral point ascends firstly; with the consolidation of soil

the depth of the neutral point becomes deeper; then the neutral point position is unaltered at the end of soil consolidation.