Prediction of performance of MSE embankment using steel grids on soft Bangkok clay

The behavior of a full scale test reinforced wall/embankment on Bangkok clay has been predicted by finite element method. In the numerical modelling, two aspects have been emphasized: (1) selecting proper soil/reinforcement interface properties according to the relative displacement pattern (direct shear or pullout) of the upper and lower interface elements between soil and reinforcement; and (2) simulating the actual construction process by updating the node coordinates including those of the wall or embankment elements above the current construction level which ensures that the applied fill thickness simulate the actual field value. Finite element results were compared with the field data in terms of excess pore pressures, settlements, lateral displacements, tension forces in the reinforcements, and base pressures. It was found that the foundation settlements and the wall face lateral displacements were predicted reasonably well. In addition, the predicted pore pressures, tension forces in reinforcements, foundation lateral displacements, and embankment base pressures agreed fairly with measured values. Several factors, such as permeability variation of the foundation soil and compaction effects of embankment fill have also been investigated. Furthermore, some of the deficiencies in finite element modelling are also discussed.