Abstract
The vacuum pre-loading is advantageous over the conventional pre-loading method since the effective stress increase in the ground may be achieved by having comparatively small-scale equipment and by avoiding any danger of ground failure during embankment. Currently, this method suffers from a drawback that neither the strength nor the deformation of subsoil during and after the pre-loading is systematically manifested. In this study, negative pore water pressure loaded to specimen, which assumed the stress state of the original ground in triaxial testing system. From the test results, the authors proposed to recognize that the strength increase after vaccum preloading is due to the “preconsolidation effect” and pointed out the importance of assessing effective stress change after the discharge of vacuum.
