Prefabricated Vertical Drain (PVD)

One of the most popular methods of ground improvement is the use of prefabricated vertical drain (PVD) in combination with surcharge. The time for consolidation of cohesive soils varies in proportion to the square of the drainage path length. Hence, consolidation can take years to complete due to the low permeability of cohesive soils. In order to accelerate the consolidation process PVD are installed to reduce the length of drainage paths. The efficiency of this technique is enhanced by the fact that most soils have greater horizontal than vertical permeability and installed drians ensure a regime of short drainage.