Because the self-weight of the embankment layer is applied gradually, this problem uses two approaches to simulate the physical process:
Case 1 – Divide each embankment layer into six sublayers (for a total of 18 sub-layers) using three contact pairs. Twenty load steps are needed.
Case 2 – Use three embankment layers and three contact pairs with self-weight and Young’s modulus as functions of time and height. Five load steps are needed.
The clay layer and embankment layers are meshed with 2D four-node coupled pore-pressure-thermal elements (CPT212). Contact pairs are meshed with 2D two-node contact (CONTA172) and 2D target (TARGE169) elements.
The modified Cam-clay plasticity model, combined with porous elasticity, models the effect of voids on the elastoplastic behavior of the clay layer.