|Dual Core Integrated Wick Drain|
Wick drains, also known as Prefabricated Vertical Drains (PVD), significantly increase the speed of consolidation of soft compressible soils and improve the shear strength prior to construction. Wick drains consist of a prefabricated geotextile filter-wrapped plastic strip with molded channels. In recent years dual core integrated wick drains have outperformed traditional wick drains made from separate cores and geotextile filter socks. Prefabricated Vertical Wick Drains are used throughout Asia to increase the drainage paths within the soil to be consolidated on hundreds of industrial and commercial development projects including tailing ponds and leach pads.
Dual core wick drains feature an extruded polypropylene core that allows maximum water flow and a high quality non-woven geotextile filter bonded to both sides to maintain effective filtration. The dual core integrated structure withstands installation stresses and offers improved filtration and drainage.
Wick drains are inserted into the soil through a hollow mandrel mounted on an excavator or crane mast. At the bottom of the mandrel, the PVDs are connected to an expendable anchor plate. A vibratory hammer or static method is used to force the mandrel to the design depth. The mandrel is then removed, leaving the wick drain in place.
A pattern of installed vertical wick drains provides short drainage paths for pore water, which accelerates the consolidation process and the construction schedule. The speed of consolidation can be increased by laying heavy concrete or other blocks on the above ground surface.
|Item||Unit||Type A||Type B||Type C||Test Method|
|Dual Drain Core||PE/white|
|Bonded geotextile filter||PET/white|
|Tensile Strength(Dry state)||KN/Core width||>=2.0||>=2.4||>=2.8|
|Lengthways Discharge Capacity @ 350 kPa||cm3/s||>=60||>=70||>=80||ASTM D4716|
|Lengthways Discharge Capacity @ 350kPa(buckled)||cm3/s||>=40||>=50||>=60|
|Transverse Discharge Capacity||l/s||>=1×10-1|
|Tear Strength (Lengthways)||N||>=70||>=70||>=70||ASTM D638|
|Composite repellence break||N/M||No Rupture, No Peel off|
|Lengthways tensile strength(dry state)||N/cm||>=25||>=30||>=30||ASTM D638|
|Transverse tensile strength(wet state)||N/cm||>=25||>=25||>=25||ASTM D638|
|Filter permittivity||cm/s||>=5.0×10-3||At water 24hours|
|Apparent Opening Size||mm||<=0.10|