Finite Element Analysis of Subgrade Rutting Behaviour of Flexible Pavements with Terrasil and Zycobond Stabilized Black-Cotton Soil

Abstract

This study mainly focused on evaluating the maximum vertical compressive strains and permanent strains at the top of the subgrade with black-cotton soil stabilized with terrasil and zycobond in flexible pavements using finite element analysis. Firstly, a 2-dimensional finite-element model was developed for 4 layered flexible pavements with the bonded interfaces. All the four layers were modelled as elastic materials for evaluating the maximum subgrade strains for a contact pressure of 0.56 MPa and 0.8 MPa. Later, the subgrade was modelled as Mohr-Coulomb plasticity model for evaluating the initiation of permanent strains and thus failure load. The change in cohesion of terrasil, zycobond stabilized back-cotton soils showed significant change in failure loads whereas the friction angle showed minimal influence on failure loads. The results showed significantly increased failure loads with the increase in thickness of bituminous concrete layer.