Drainage performance of wicking woven and nonwoven geotextiles in virgin and recycled aggregate considering freeze-thaw effects

Wicking geotextiles have been introduced with the aim of improving and accelerating drainage under both saturated and unsaturated soil conditions. This study evaluates the hydraulic performance of three wicking geotextile products in comparison with a control test without geotextiles. The tested wicking materials included one nonwoven and two wicking woven geotextiles. Laboratory experiments were conducted using a soil column test box incorporating a trench system, where the geotextiles were installed beneath the soil column and bent into a trench full of uniformly sized aggregate to simulate urban road subdrain conditions. Base materials investigated included virgin crushed limestone and recycled concrete aggregate. The soil was saturated and subsequently allowed to drain and monitored with moisture sensors. To assess potential suitability in cold regions, additional tests were performed after subjecting the soil column with geotextiles to one freeze-thaw cycle. Environmental scanning electron microscopy analyses were performed on the geotextile samples before and after freeze-thaw exposure. The results demonstrate that wicking geotextiles can significantly enhance the overall drainage performance of granular layers compared with the control section with varied improvement depending on the geotextile and fill material types. Freeze-thaw cycling influenced drainage efficiency and continued to outperform the control section after the conditioning.