RELIABILITY-BASED PAVEMENT DESIGN MODEL ACCOUNTING FOR INHERENT VARIABILITY OF DESIGN PARAMETERS

The basic premise of pavement design procedures employed in Mechanistic Empirical (ME) approaches are widely accepted. However, several issues need to be resolved before implementing ME pavement design procedure in practice. One of the issues is that the design procedure should provide a consistent pavement performance level considering inherent variability associated with design input parameters. For a complete ME pavement design procedure, the effects of the inherent variability of input design parameters on predicted pavement performance must be addressed and quantified. Some of the key principles for applying the reliability concept to ME pavement design are presented to account for the inherent variability of design parameters in this paper. In particular, the selection of an appropriate reliability assessment technique and careful characterization of design input variability were considered because of their central role in calculating the reliability of pavement performance and determining the reliability-based safety factor of the pavement design procedure. In addition, a reliability analysis model for evaluating uncertainties in the ME flexible pavement design procedure and a reliability-based pavement design approach using Load and Resistance Factor Design (LRFD) format are introduced.