2020 Volume 15 Issue 1 Pages 53-66
The authors applied the idea of "Structural calculation of superstructure by seismic design based on energy balance method" to the ground and developed a liquefaction evaluation method. The basic idea of this proposed method is as follows, 1) Input energy of whole ground is calculated by energy spectrum, 2) Input energy is distributed to each layer as accumulate plastic strain energy, 3) degree of liquefaction damage is evaluated from the relationship between accumulate plastic strain energy and volumetric strain of each layer. In this paper, case study analysis were conducted with stress method and energy balance method under the same condition for virtual grounds, and the settlement amount was compared. The correction factor was required for an appropriated evaluation in the stress method while energy method requires no correction factor. The energy spectrum can be a good indicator of magnitude of seismic motion, if the intensity of seismic motion is defined by the magnitude of settlement caused by liquefaction. As a result, it was found that there was no significant difference in the evaluation of the settlement amount between the stress method and the energy method within the scope of these cases in this study.