Design Parameters for Geotextile-Reinforced Unpaved Road by Applying Dimensional Analysis

Soil swelling in road layer is the complex phenomenon. The paper aims to derive a concise expression for two challenging design parameters when the subgrade layer is expansive in geotextile-reinforced unpaved road. The design parameters considered in the present study are the mobilized bearing capacity and swelling pressure for expansive soil. Herein the dimensional analysis via Buckingham’s π method is applied to derive the design parameters by forming the dimensionless group for prototype and model system. The model testing for the swelling pressure and mobilized bearing capacity are carried out in the laboratory by using consolidometer ring and CBR set up. The test results reveal the swelling pressure of 22.03kN/m² for the soil sample having 76% as degree of saturation. A linear relation is observed between swelling pressure and degree of saturation and becomes equal upon surcharge. The mobilized bearing capacity for the expansive soil sample is 0.47kg/cm². The failure pattern observed during testing is general shear failure in unsoaked condition and punching soil failure in soaked condition. The paper provides geometric ratio of 1:6 for model and prototype and also suggests modification in Giroud and Han generic equation by including the developed dimensionless group.