Failure modeling of alluvial foundations due to boiling: numerical modeling versus experiments

The sheet piles are used below hydraulic structures to reduce seepage flow rate and hydraulic gradient at the outlet of such structures rested on permeable foundations. Up to now, for analysis of seepage under hydraulic structures much research work has been carried out in the form of numerical models. However, less field and laboratory works have been performed to study and compare boiling phenomena for evaluating of the numerical models. By simulating an experimental model of a sheet pile inserted in a sand foundation by computer code FLAC based on the finite difference method, the soil behavior mechanism flow has been investigated under seepage effect. The results indicate that computer code FLAC underestimated uplift pressures compared to the experimental data. In order to study the boiling, the soil treatment analyzed at the most critical condition as well. The numerical model presented in computer code FLAC, is properly able to simulate the soil and foundation behavior. Comparing the results obtained from numerical model with experimental data also confirms well, because this model predicts the boiling observations with reasonable accuracy and it was possible to predict heaving mechanism based on the stress analysis before performing the plan.