Study of Stabilized Expansive Soil as Subgrade under Extreme Climatic Conditions: Fid-Bau Portal

Study of Stabilized Expansive Soil as Subgrade under Extreme Climatic Conditions

Mudliar, Richa / Sathiyamoorthy, Rajesh

Heaving is a common problem experienced with the high-plasticity clays due to water-absorption in pavement structures. Under an excessive amount of precipitation, typically in humid areas, water infiltration and absorption can lead to significant heaving on the surface of the subgrade. If this type of situation is not monitored properly, it can lead to excessive stress at the base of the pavement which in turn can lead to tensile cracks at the surface and can lead to disastrous effects. To overcome these typical problems, the in situ high-plasticity clays in subgrade are often replaced with chemically stabilized soil up to a certain depth. The chemically stabilized soil prevents a significant amount of heaving at the surface by reducing the swelling potential of the high-plasticity clays to a great extent. In this study, a nontraditional stabilizer, namely, lignosulfonate has been chosen and compared for the enhancement of the performance of the subgrade system. Basic tests are carried out to ascertain the effects of chemicals. Swell tests, followed by consolidation and UCS tests have been performed to fix the optimum amount of chemical. Further, to check on the efficacy of the stabilized soil in a pavement utilizing the optimum amount, a brief numerical analysis has been carried out to estimate the heaving in a humid region at different intervals of a year. Lignosulfonate has been found to give good results in terms of a decrease in heaving at an optimum content of 3% of the mass of soil.