This report aims to develop a three-dimensional effective stress analysis method in which soil properties can easily be set from the results of conventional tests. The excess pore water pressure buildup in the saturated soil in the three-dimensional analysis is evaluated based on the extension of the cumulative damage concept in a one-dimensional case in which the liquefaction strength curve is expressed as a relation between shear stress amplitude and number of cycles. The proposed method is validated by simulating three dimensional blast-induced shaking experiment conducted on a large soil-pile-structure models. It is important to notice that three directional input motions are critically important, since one directional input motion could not obtain good agreement with the experiment.
