Experimental Study on the Swelling Behavior of Expansive Soil Reinforced with Coir Geotextile

Abstract

Structures constructed on expansive soils are experiencing a higher upward pressure due to swelling–shrinkage nature of expansive soil. India is having 15–20% land with expansive soil and causes severe damages to the existing structure like pavement, dams, multi-story building, retaining wall, etc. This study investigated and identified the mechanisms by which swelling pressure can be mitigated in expansive clay soil. The single layer of coir geotextile is used with the treatment of lime and silica fume. The coir treatment is made to enhance the efficiency of coir geotextile to reduce the swelling pressure of expansive soil subgrade. Chemical and microstructural component of expansive soil sample is investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared (FTIR). The constant volume swell pressure test with and without treatment of coir geotextile mat has been carried out. The experimental result analyzed which indicates that the lime-treated coir geotextile mat significantly reduces the upward swell pressure and heave of expansive soil subgrade.