Abstract
This paper describes the stability of improved ground by densification method during and after liquefaction. It is generally known that possibility of liquefaction in the improved ground during earthquake is very low. However, it is concerned that the improved ground tends to be influenced by propagation of excess pore water pressure from liquefied ground surrounding the improvement. Therefore, in this study, a series of triaxial and torsional tests was carried out under various different conditions of effective confining stresses, relative densities, anisotropic effective confining stresses and fine contents, in order to investigate the influence of dissipation of excess pore water pressure to shear modulus and post-liquefaction deformation characteristics of loose-to-dense sands. As a result, it was confirmed that the generation condition of excess pore water pressure lead to the difference of the residual deformation of the improved ground after liquefaction.
