Prefabricated Vertical Drains

For construction of structures on sites underlain by thick strata of soft cohesive soils, a method of foundation soil improvement is generally required to prevent bearing capacity failure and or to avoid excessive total and differential settlements. These soft soils have a very low bearing capacity to due to their saturated state, the PVD’s are used to increase the bearing capacity of the soil by removing the excessive water present inside.

The water is trapped inside the soft cohesive soils, and the consolidation of which will require a long period. The PVD’s provide the path for the trapped water to come out of the soil, thus accelerating the rate of consolidation.

Historically the design of structures on soft compressible soils (clays) has created problems for civil engineers. Construction without some sort of soil treatment is usually impractical due to unpredictable long-term settlement. Although surcharging increases water pore pressure, settlement can take considerable time, often years, as the water lacks an easy path to leave the soil.

Consolidation of soft cohesive soils using prefabricated vertical drains (also called wick drains or band drains) can reduce settlement times from years to months. Most settlement can occur during construction, thus keeping post-construction settlement to a minimum.

Applications of Prefabricated Vertical Drains

• Construction of Road, Railway Embankment, Airport and Ports
• Industrial Projects
• Land Reclamation Projects