Efficient reliability-based approach for mechanistic-empirical asphalt pavement design

An efficient approach for reliability-based mechanistic-empirical pavement design considering fatigue and rutting failures is developed in this study. This efficient approach relies on the first-order reliability method (FORM) and is implemented in a spreadsheet. The gamma sensitivity study is performed to identify the key input parameters in the reliability analysis. This study investigates the effect of the uncertainty in elastic modulus, layer thickness, design traffic as well as the model error of a three-layered pavement system on the reliability analysis. Comparison study shows that this efficient approach using FORM can yield results that are comparable with those obtained using Monte Carlo simulation. The advantages of this efficient approach include: it requires much less computational effort to determine probability of failure; it can be readily adapted for other mechanistic-empirical models for pavement design; it is easy to be adopted in the engineering practice and thus has the potential to become a practice tool in the reliability-based mechanistic-empirical pavement design.