CeTeau

The use of CeTeau composite strip drains for lateral drainage on Prefabricated Vertical Drain (Wick Drain) projects can provide a cost-effective, positive, and quantifiable alternative to the use of a sand or granular drainage blanket.

Strip drains are placed under the surcharge to receive the flow from the vertical drains and conduct it laterally to discharge points at the edge of the surcharge. In most cases the installation of these alternatives are less expensive than a granular drainage blanket. By providing a low resistance drainage path for relief of excess pore water pressures, vertical prefabricated drains (wick drains) drastically shorten consolidation times in soft cohesive soils. Used with a surcharge load, vertical drains are a cost-effective method for improving these soils. For vertical drains to function properly, a drainage path must be provided to receive flow from the drains and conduct it from under the surcharge to appropriate discharge points. This lateral drainage system must perform without applying excessive back-pressure to the vertical drains, thus delaying the consolidation process. The traditional method of providing lateral drainage has been to install a sand layer, usually about 1 m thick, under the surcharge. Most of the conventional analyses overestimate the flow capacity of sand drainage blankets resulting in inadequate lateral drainage that, in a number of cases, has compromised the function of the vertical drain system.