Deformation dependencies of sand stiffness

Abstract

Convention does not provide a solution combining drained and undrained response, loss and recovery of sand stiffness, all in one irregular loading sequence. Alas, such solution is necessary for designing offshore wind turbine foundations and predicting soil behavior during (and after) seismic events. To gain deeper understanding of the fundamental phenomenon governing disturbed sand behavior, unconventional testing procedures were attempted using a frictionless triaxial apparatus. The resulting observations revealed a new physical phenomenon (deformation dependent stiffness hysteresis loops). The new observations were then used to derive an unconventional model (BSM), which uses a strain (deformation) envelope.