Comparison of Seismic Ground Response Analyses Under Large Earthquakes

Abstract

Equivalent linear, truly nonlinear, and effective stress analyses are compared at 268 sites under 11 large earthquake motions in order to grasp general feature of the applicability of the equivalent linear method and total stress analysis. Equivalent linear analysis shows larger peak acceleration and smaller peak displacement than total stress nonlinear analysis, but other indices such as instrumental seismic intensity, peak velocity, and spectral intensity are nearly same to each other. Therefore, it is applicable when truly nonlinear analysis is applicable. On the other hand, all earthquake motion indices are much smaller in the effective stress analysis compared with the total stress analysis at the liquefiable sites, except two indices peak ground displacement and maximum strain that are much larger. Therefore, it is recommended to use effective stress analysis at these sites. However, as indices are overestimated, use of the total stress can be said to result in conservative design when inertia force is interested at.