Effect of Polypropylene Planar Reinforcement on the Unconsolidated Undrained Behavior of Black Cotton Soil

Abstract

Black cotton soil is very compressible and cohesive with extremely low bearing capacity. This study’s objective is to enhance the shear parameters such as the internal friction angle and cohesion of black cotton soil, thereby enhancing the bearing capacity of the soil. For the present study, soil sampling has been carried out near Kollegal, Karnataka. The coordinates of the site are 12° 08′ 21.0″ N and 77° 04′ 59.0″ E. The undisturbed and representative soil samples have been extracted from three different geographical locations at different depths. A detailed experimental study has been carried out to determine the physical, index, and engineering properties. Cohesion and the internal friction angle determined for the soil under consideration were 0.05 N/mm² and 0°, respectively. To increase the internal friction angle of soil, polypropylene planar reinforcements were introduced. Reinforcements were introduced. Unconsolidated undrained (UU) triaxial tests were conducted on planar reinforced soil. Reinforcements were introduced in the soil specimen with one, two, and three individual layers, and results demonstrate that cohesion was increased marginally to 0.057 N/mm², 0.059 N/mm², and 0.061 N/mm², and the internal friction angle was increased to 2.7°, 4.2°, and 6.6°, respectively.