EQUIVALENT LINEAR ANALYSIS TAKING INTO ACCOUNT EXESS PORE PRESSURE BUILT-UP DUE TO LIQUEFACTION

This paper introduces a practical earthquake response analysis method to evaluate liquefaction phenomena based on the dynamic effective stress analysis. The method is based on a cycle-wise equivalent linear analysis, in which equivalent stiffness is evaluated in a half-cycle of shear strain time history. This method enables to evaluate not only non-linearity due to strain but also due to liquefaction. The liquefaction is evaluated from liquefaction strength curves of each soil layers, so engineers can directly specify input parameters of the analysis from a report of soil investigation. The theory and verification studies for observed earthquake data are presented. Examples of application to estimate soil springs and ground deformation are also presented.