Study on Degradation of Natural Coir Geotextile and Its Performance Assessment Using Coating Materials

With features including improved drainage, soil stabilization, and erosion management, natural geotextiles have become essential components in the construction of roads. The incorporation of coir geotextile reinforcement has the potential to enhance the structural performance of pavements, extend their lifespan, and mitigate settlement issues caused by subgrade soil instability. One of the objectives of this study is to evaluate both fresh coir sample and already laid coir geotextile sample from 2 different study areas chosen at Thiruvananthapuram, Kerala, through laboratory testing using Scanning Electron Microscopy (SEM). The second objective is to investigate the potential for enhancing geotextile performance through the application of different coatings: used cooking oil, paint, and bitumen, each offering unique properties and benefits. Even though the coir geotextile is said to have a life span of five years, from the study it was seen that the coir geotextile which was laid in the road for almost 12 and 18 months, was severely degraded. SEM analysis showed large cracks and pores in coir geotextile, which promoted the water absorption and thus degradation. Thus, to improve the lifespan, the coir geotextile was coated with three materials. The findings revealed that used cooking oil and paint showed inconsistent performance and limited effectiveness as a coating material. Bitumen emerged as more reliable option for improving the performance of coir geotextiles. Improved understanding of how coatings influence geotextile performance can lead to more sustainable construction practices, resulting in cost savings, enhanced structural integrity, and prolonged service life for transportation infrastructure.