Abstract
Empirical approach is in use for the designing of granular or low volume pavements in many countries, including India. These types of pavements mainly comprise of unbound granular material layer over subgrade with thin asphalt surfacing. Accurate modeling of the granular material is essential for better correlation of the identified mechanistic responses with the performance of pavements. It is known that, unbound materials are nonlinear and have stress dependent resilient modulus. Hence, the stress dependency of unbound materials should be considered for an accurate estimation of true pavement responses. Writing suitable codes in Finite Element (FE) analysis software, model the nonlinearity of unbound granular layers. A 3-D FE was developed and analyzed. It was observed that the pavement responses obtained from the 3-D FE analysis carried out for typical low volume pavements taking into account the nonlinear characteristics of unbound pavement materials differ by 34% to 44% from those obtained using linear analysis.
