ABSTRACT
The energy method for the analysis of densification and liquefaction of cohesionless soils is based on the fact that during deformation of these soils under dynamic loads, part of the energy is dissipated into the soil. Extensive research has been conducted during the last decade, to introduce and evaluate the energy concept. A total of 30 dynamic centrifuge tests at a scale of 50 and 60 g’s were conducted on scaled pore fluid-saturated models to evaluate the energy method in determining the liquefaction potential of a soil deposit subjected to dynamic loads. The influence ofrelative density, effective confining pressure and grain size distribution on the energy per unit volume required for liquefaction was studied. A simplified procedure for reconstructing the shear stress-strain history to liquefaction at different depths, within the prototype, as well as for calculating the energy per unit volume from the recorded horizontal accelerations and lateral displacements within the model was developed. Generalized relationships were obtained by performing regression analyses between the energy per unit volume at the onset of liquefaction and liquefaction affecting parameters. The equations are statistically compared with previously developed relationships from the results of torsional shear liquefaction tests. The comparison reaffirms the great promise of the energy method as a robust procedure for evaluating the liquefaction potential of a soil deposit.
