Key Trends in Liquefaction-Induced Building Settlement

Abstract

Dynamic soil-structure interaction effective stress analyses are performed to identify key trends in the settlement of buildings with shallow foundations affected by soil liquefaction. Over 1,3 analyses are performed by systematically varying subsurface conditions and building properties while applying 36 earthquake motions. Shear-induced soil deformation mechanisms govern during strong shaking, whereas volumetric-induced deformation mechanisms contribute more significantly after shaking. The analytical results identify the key parameters controlling shear-induced building settlement due to liquefaction. The relative density of the liquefiable layer is the key soil engineering property, and its thickness and depth are important soil profile characteristics. Building contact pressure is the most important building parameter, and building width is also important. The ground motion intensity parameters that correlate best with building settlement are standardized cumulative absolute velocity, Arias intensity, and 5% damped 1-s spectral acceleration. The postliquefaction bearing capacity factor of safety indicates when large building settlements are possible.