Numerical Simulations of LEAP Centrifuge Experiments Using a Multi-surface Cyclic Plasticity Sand Model

Numerical simulations of LEAP-UCD-2017 centrifuge tests are conducted using a multi-surface cyclic plasticity sand model implemented with the characteristics of dilatancy, cyclic mobility and associated shear deformation. This model extends the OpenSees PDMY03 material to include the Lade-Duncan failure criterion as the yield function, thus allowing for considerable accuracy in three-dimensional shear response conditions. For this study, the model parameters are calibrated based on a series of available cyclic stress-controlled triaxial tests of Ottawa F-65 sand with relative density D_r. = 65%. Using the calibrated model parameters, Finite Element (FE) simulations are performed for dynamic centrifuge tests of a liquefiable sloping ground. The computed results are systematically presented and directly compared to the centrifuge test data. An overall good match between the simulations and measurements demonstrated that the multi-surface cyclic plasticity model has capabilities for simulating the stress path of cyclic stress-controlled triaxial tests as well as the response of the liquefiable sloping ground subjected to seismically-induced liquefaction.