Finite Element Analysis of Equivalent Diameter of Prefabricated Vertical Drains

To clarify some of the inconsistencies in the research of equivalent diameter of PVDs, we constructed 3-D consolidation models of PVDs and sand drains using ABAQUS and compared models with and without sand drain resistance. When the sand drain resistance was included in the model, the equivalent diameters of the sand drains were 30, 65, 78, and 100 mm (for a 100-mm-wide, 4-mm-thick PVD) corresponding to PVD drainage depths (or soft soil layer thickness) of 2, 5, 8, and 10 m. Except for the depth of 2 m, the other results were higher than the values found in previous studies. The equivalent diameters increased with increasing consolidation depths. When the well resistance was ignored, the equivalent diameters were 20 mm for all the ground consolidation depths, which was less than the value in most previous research findings.