The State of Qatar is experiencing tremendous growth in infrastructure including road network and highways. The current methods used in design of asphalt pavements in the State of Qatar are empirical and might not be suitable for the design of long-lasting pavements. Given the significant increase in traffic, road authorities in the State of Qatar have been considering the use of mechanistic-empirical methods in the design and analysis of asphalt pavements. This study documents the results of a study in which the mechanistic-empirical pavement design guide (M-E PDG) software was used in the design of asphalt pavements with input parameters that were carefully selected to reresent local materials and climatic conditions. The selection of material properties was based primarily on specifications and design guides in the State of Qatar and on published literature about these materials. The mechanistic-empirical method was also used to assess the benefits of adopting the concepts of perpetual pavement design and also to compare the performance of pavement structures in which various bitumen grades, granular bases and chemically stabilised sub-base were used. A life-cycle cost analysis was carried out to determine the design with the highest net present value among the various options investigated. It is expected that the outcomes of this study would promote the use of mechanistic-empirical methods in the State of Qatar and the region. Inevitably, this will require significant efforts to calibrate material and damage prediction models used in the M-E PDG for more accurate representation of material properties and measured pavements performance.

Reliability has been incorporated in many pavement design procedures to account for the effects of inputs variabilities and uncertainties on predicted performance. The American Association of State Highway and Transportation Officials (AASHTO) mechanistic empirical pavement design guide (MEPDG) computes the reliability of pavement sections with the assumption that the variability of predicted distresses follows normal distribution. This approach does not account for the systematic contribution of each design input variability on the overall output variance. This paper evaluates a two-component reliability analysis methodology for pavement application. The two-component reliability analysis methodology uses a response surface method (RSM) for a surrogate model generation and the first order reliability method (FORM) for reliability computation. Three different response surface methods (central composite, Box–Behnken and Doehlert designs) were implemented and statistically verified for their suitability for surrogate model generation. The two-component reliability analysis methodology was further utilized for the generation of partial safety factors for the development of a load and resistance factor design (LRFD) procedure for pavement applications. Field pavement sections with a wide range in design inputs and target reliabilities were used to evaluate the proposed reliability analysis methodology. The results have shown that the three RSM can be used effectively for pavement reliability problems.

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