The behaviour of ground during dynamic compaction method

The purpose of this study is to evaluate for the soil behaviours in heavy tamping based on both the results of some impulsive loading triaxial tests and a lot of in-situ data. It was found that the change of stress in the ground took place instantly in falling hammer and it was important to estimate for induced pore pressure accurately when we evaluated for the effects of ground improvement quantitatively. Therefore, we investigated the relationship between loading stress and induced pore pressure in detail based on the results of laboratory tests and FEM dynamic analysis by means of Biot's two phase fixed model. Finally, combining the predicted method for the change of void ratio proposed in this paper, which was based on impulsive loading tests' results, with FEM analysis on in-situ problem, the degree of ground improvement was evaluated in each element in the ground.