Patent attributes
A bi-layer, woven geotextile fabric has interwoven first and second layers. The first layer is over and under woven through the second layer in a pre-determined pattern so that the first layer has portions which face a first side of the second layer and portions which face a second side of the second layer. Monofilaments in the warp direction of the first layer have a pre-determined differential heat shrinkage characteristic that is greater than the monofilaments in the warp direction of the second layer. Closed cells defined by the pattern of the over and under weave are disposed on the first and second sides of the second layer. Shrinkage of the monofilaments in the warp direction of the first layer provide for a separation of a portion of the second layer from the first layer at the cells.
