ABSTRACT
ABSTRACT: This paper presents results from a study that uses an in-house developed finite element analysis program, FEP++. In this work, the asphalt concrete layers are considered as linear viscoelastic and the unbound layers as linear elastic. The advantage of using this level of complexity is that it offers an improved representation of asphalt concrete pavements while using the same inputs that are required for the NCHRP 1-37A Mechanistic Empirical Pavement Design Guide. After using the finite element package to assess the impacts of wheel speed, temperature gradient, and material type on pavement response, attention turns towards an advanced mechanistic material model for predicting the fatigue response of asphalt concrete, i.e., the viscoelastic continuum damage (VECD) model. This model is characterized using mixtures from the Federal Highway Administration’s Accelerated Load Facility (FHWA ALF) and is found to capture an underlying material property, the damage characteristic relationship. Finally, results from FEP++ simulations of the FHWA ALF pavements are combined, in a simplified modeling scheme, with the VECD model to predict the fatigue performance of these pavements.
