Centrifugal and numerical modelling of reinforced embankments on soft clay installed with wick drains

Abstract Centrifuge models and finite element analyses of reinforced embankments on soft clay (with or without wick drains) are presented. The results obtained from the centrifuge tests were compared with those from the finite element analyses and were found to be in good agreement. For the case of reinforced embankments on soft clay installed with wick drains, it was found that the magnitude of maximum tension in the reinforcement was slightly higher than that for the case of no wick drains. Also, the distribution of tension in the reinforcement was much more localised under the shoulder of the embankment for the wick drain case as compared to the case of no wick drains. Base reinforcement of embankment is effective in situations, where the demanded shear strength of the clay foundation marginally exceeds the available shear strength. The presence of wick drains in soft clay increases the strength of the clay foundation significantly during the period of embankment construction. This gain in shear strength ensures better mobilization of tension in the reinforcement and contributes significantly towards the stability of the embankment.

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