Abstract: DJM(Dry Jet Mixing) combined with PVD(Plastic Vertical Drain) method was a new soft ground improvement method(2D method).A simplified consolidation calculation model of the ground improved by 2D method was presented,and the formulas of excess pore water pressure and consolidation degree were derived.Taking as double layer ground composed of composite ground and underlying layer,a consolidation calculation program based on consolidation theory was compiled for 2D method,which could represent the continuity of pore water pressure between the two layers.The comparison between the calculated results and the filed measured data showed that the calculated excess pore water pressure,the consolidation degree and the settlement-time relationship were consistent with those of field data respectively.