FINITE-ELEMENT MODELING OF VERTICAL DRAINS BENEATH EMBANKMENTS ON SOFT GROUND

A methodology is described for modelling vertical drains in plane strain finite element analyses of embankments on soft ground. This includes the use of a suitably formulated drainage element to represent each drain. Criteria for matching the effect of a single drain in axisymmetric and plane strain analyses are developed on the basis of a widely accepted theory. Matching can be achieved by adjusting the geometry (drain spacing) and/or the permeability of the soil. The finite element analysis and matching procedure are validated by comparison with theoretical results; the effects of both finite drain permeability (well resistance) and smear are modelled satisfactorily.