Reliability assessment of the physical modeling of liquefaction-induced effects on shallow foundations considering nonuniformity in the centrifuge model

Physical modeling has been widely used to simulate geotechnical earthquake engineering-related problems and to validate finite element numerical models. In both cases, the model ground is usually considered to have uniform soil properties. However, the model ground is prone to spatial nonuniformity and may affect engineering judgment based on physical modeling. This paper presents a reliability assessment of the physical modeling of liquefaction-induced effects on shallow foundations considering the spatial variability in the centrifuge model. Two-dimensional (2D) finite element simulations with the PM4Sand (version 3.1) elastoplastic soil constitutive model are performed for a sufficient number of stochastic realizations. The nonuniformity in the centrifuge model is implemented with stochastic realizations of the overburden and energy-corrected, equivalent clean sand, SPT (N1)(60cs), values using a spatially correlated Gaussian random field. The reliability of the centrifuge model test is assessed based on the stochastic average settlement and tilt of the foundation-structure system. The implications of the nonuniformity in the centrifuge model on the liquefaction extent of the ground and spectral displacement of the foundation are also investigated.