Evaluating the Drainage Performance of Wicking Geotextile Under Freeze–Thaw Conditions below Pavement Infrastructure

Pavements constructed on frost-susceptible subgrades are often subjected to distress because of cyclic freeze–thaw (F–T) conditions resulting from seasonal temperature variations. Cyclic frost heaving significantly affects the long-term performance of pavements, particularly during the thawing phase, where excess water weakens the subgrade. Numerous solutions have been studied to mitigate these issues, including soil stabilization, soil replacement, and drainage improvements using geosynthetics. Traditionally, many woven and non-woven geotextiles have been used to remove excess water; they are effective at draining water under saturated conditions. However, they are ineffective at removing moisture under unsaturated conditions because they cannot provide sufficient capillary suction. A new type of geotextile—the wicking geotextile—has been introduced, with finer, deeper grooves to generate higher capillary suction, aiding the extraction and transport of excess moisture even in unsaturated conditions. In this paper, a research study was designed to evaluate the performance of the wicking geotextile under cyclic F–T conditions. Large-scale laboratory tests with an unreinforced control section (CS) and a reinforced section (RS) were designed using frost-susceptible soils. The test setup was subjected to two F–T cycles under controlled temperature conditions with freezing temperature set at −18°C (−0.4°F). The results showed the wicking geotextile effectively removed and transported moisture, thereby reducing water content in the RS subbase by 51% and in the subgrade by 7% compared with CS. It also helped redistribute moisture uniformly across the pavement layers and maintained steady drainage even after cyclic F–T, indicating consistent performance under harsh environmental conditions.