Development of an enhanced pavement mechanistic-empirical analysis tool for developing structural deterioration models

Abstract

ABSTRACT AASHTO's Pavement Mechanistic-Empirical Design (PME) inserts the computed structural responses in the calibrated transfer functions to predict pavement distresses. However, the asphalt layer modulus is not adjusted based on the accumulated fatigue damage over the design period. This limitation negatively impacts the mechanistic part of the design procedure, making the predicted distresses more dependent on the reliability of transfer functions in the empirical part. Besides, computing actual pavement responses assists in forecasting structural deficiencies over the analysis period and planning the optimal treatment scenario through a multi-year prioritisation at the network level. Hence, a standalone application called Enhanced-PME (EPME) was developed in this study which accounts for the deterioration in asphalt layer modulus due to the accumulated fatigue damage and computes the representative pavement responses. EPME extracts traffic data, climate conditions, and material characteristics from the PME while modifying the asphalt layer modulus using a user-defined damage function. Also, a structural deterioration model for predicting effective structural number is developed in this study to demonstrate the application of EPME. The SN prediction model is validated and then implemented in two case studies, highlighting the benefits of utilising structural deterioration models in the Pavement Management System (PMS).