Simulation of Monotonic and Cyclic Soil Behavior using a Kinematic Hardening Plasticity Model

In this paper we investigate the PM4Sand plasticity model developed by Boulanger and Ziotopoulou in predicting soil behavior under cyclic loading. PM4Sand is a constitutive model based on the earlier Dafalias-Manzari model and builds on critical state soil mechanics theory. PM4Sand uses a two-surface kinematic yield surface in modeling soil behavior and more importantly considers the effect of fabric change and void ratio evolution during loading. The model works robustly over a wide range of loading conditions and stress paths. It was calibrated by Boulanger and Ziotopoulou at different relative densities under a range of confining pressures. In this study, we implemented the model in a MATLAB script and further calibrated it with test data in the literature. Results from earlier experimental studies on Fuji River sand and Sacramento River sand at different relative densities and confining pressures were used in our calibration efforts. Simulated and measured values of number of cycles to liquefaction triggering were compared. The results have shown that PM4Sand can predict the number of cycles to liquefaction with considerable accuracy for a variety of cyclic load levels for these sands at different relative densities consolidated to a wide range of confining pressures