Laboratory Model Study on Erosion Control Using Coir Geotextile

Soil erosion is the most significant geohazard in slopes. Soil's susceptibility to erode is influenced by different climatic, physical, hydrological, chemical, mineralogical, and biological properties. Erosion mainly takes place when excessive surface runoff flows with high velocity. Prolonged soil erosion will lead to the reduction of the soil cover and leads to slope failure. Erosion is predominant in Nilgiris, Western Ghats which is selected as the study area. In this district, undisturbed soil samples were collected and tested for various physical properties to assess the factor of erodibility. Research done in the field of erosion control suggests different surface treatment methods to reduce soil loss. The effectiveness of surface treatment on erosion control is mostly studied to calculate the soil erosion rates conducted on slope models. In this study, the erosion control on slopes is tested with the help of fabricated slope model with the surface application of coir geotextile which is a geonatural material, and its degradability was reduced by treating it with asphalt emulsion. Erosion tests were conducted for different rainfall intensities on slopes by varying the slope inclination as 10°, 20°, and 30° using a constant head rainfall simulator. The reduction in erosion rate after surface treatment is obtained, and suitable surface application is recommended in sites of higher soil loss.