The Research to Obtain Fine Grained Soil´s Maximum Dry Density by Fast Consolidation Compression Method

There are disadvantages both large amount of sampling quantity and large amount of labor when using compaction method to get maximum dry-density, so fast consolidation compress method is recommended. A soil sample come from Nanjing-Qidong existing railway embankment, and the sample´s dry-density is 1.63g/cm3 according to compaction method. Then undisturbed soil samples are tested under water immersed and non-immersed conditions, tests show that immersed sample needs lower compress consolidated pressure to obtain maximum dry-density. To obtain disturbed sample´s maximum dry-density, standard and rapid consolidation compression method are used. Contrast tests show that sample´s dry-density increased with consolidation pressure, and the 15 hits´ sample compress consolidation pressure is relatively stable to reach maximum dry-density. Under 450kPa consolidation pressure, errors between dry-density of standard consolidation compression method and fast consolidation compression method and maximum dry-density is less than 1%. Considering fast consolidation method test time is short, so it is recommended to get maximum dry-density in existing railway.