Tensile strength freeze-thaw durability of a biaxial geogrid and wicking geogrid composite

A relatively new geosynthetic material, known as a wicking geogrid composite, consists of a biaxial geogrid bonded to a nonwoven wicking geotextile. This system offers dual functionality by providing structural reinforcement while simultaneously managing moisture in both saturated and unsaturated conditions. In cold regions, it may help mitigate the detrimental effects of freeze-thaw cycles, including frost heave and frost boil. However, few studies have examined how repeated freeze-thaw exposure influences mechanical performance. This study investigates the tensile behavior of a biaxial geogrid and wicking geogrid composite subjected to repeated freeze-thaw cycling. This includes short-term cycles (15, 25, 35 cycles of 24 h freeze at −7°C ± 1°C/24 h thaw) and long-term cycles (three cycles each lasting 4 months). Results indicate a minor effect of the short-term cycles on tensile strength for the biaxial geogrid. The wicking geogrid composite showed notable tensile strength gains following the short-term cycles. The long-term freeze-thaw cycles resulted in tensile strengths lower than the normal conditions specimens for both materials. The values nevertheless exceeded the minimum average manufacturing specifications for the wicking geogrid composite, however. These findings offer insights into the durability and performance of wicking geogrid composite in cold climate applications.