Implementation Aid for Dynamic Replacement of Organic Soils with Sand

Abstract

The objective of this research was to understand the mechanism of dynamic replacement (DR) with the view of identifying the attributes needed to effectively implement it. This was achieved by analytically modeling DR of organic soils with sand using the finite-element method. First, this paper describes briefly the finite-element formulation and the calibration of the finite-element model using common laboratory soil tests. Then, model predictions are compared with observations made during a fully instrumented field DR trial. The respective laboratory tests utilized to extract the model parameters certainly confirmed the applicability of the chosen constitutive models for the relevant geomaterials involved in the field DR test. Furthermore, the analytical predictions of the drop hammer displacement and acceleration, as well as pore pressures and lateral displacements in the drop hammer vicinity, agree reasonably well with those observed during the full-scale field DR. Finally, a parametric study is performed to demonstrate the usefulness of the analytical model in predicting the optimum thickness of the initial sand blanket that would produce the maximum treatment benefits.