Durability against Wetting and Drying Cycles and Installation Damage of Water Hyacinth Geotextiles Coated with Natural Rubber Latex

Water hyacinth (WH) is abundant in tropical regions. As a result of high sources of fiber, the WH is possibly used for producing biodegradable geotextile, but WH-based geotextiles have low tensile strength and durability against the thermal environment, especially in tropical climates. Therefore, this research aims to develop a more durable geotextile by coating its surface with natural rubber (NR). The test results indicated that NR-coated WH geotextile specimens had significantly higher durability against wet/dry cycles when compared to the uncoated WH geotextile specimens because the NR could prevent the change in water content of the WH fiber in the thermal environment, and hence insignificant change in the fiber structure during wet/dry cycles. Moreover, the coating layer can also effectively minimize the damage from the sharp coarse aggregates to the geotextile during the installation. The field coated specimens had significantly higher tension force compared to the field uncoated specimens. The results of microstructure analysis confirmed that the NR acted as an impervious layer, preventing the water evaporation of woven WH geotextiles. The woven WH-NR geotextile had an ultimate tensile strength of 14.8 kN/m with corresponding strain at break of 20% and very low water absorption, which is suitable for erosion control. The outcome of this research promotes the usage of WH and NR in sustainable geotechnical applications.