Accurate determination of near-surface responses of asphalt pavements

Abstract

AbstractAccurate determination of structural responses plays a critical role in a mechanistic-empirical pavement design. A new distress model, top-down fatigue cracking, has been incorporated in the newly developed Mechanistic-Empirical Pavement Design Guide. The critical response for top-down cracking is the horizontal tensile stress or strain at the pavement surface. However, the poor convergence of analytical layered elastic solutions in the vicinity of the pavement surface may result in large errors in response results. This study uses the Lucas algorithm to effectively solve this problem. The algorithm converts the complicated oscillating behaviour of the product of Bessel functions to regular oscillations by separating the integrand into high- and low-frequency components. Thus, extrapolation techniques can be effectively applied to accelerate the convergence. A computer code is developed to implement the proposed procedure. The computer code is verified against the boundary conditions and finite element results. It is also compared to other layered elastic programs. The results show that the proposed procedure can accurately determine the near-surface responses of asphalt pavements.Keywords: asphalt pavementnear-surface responseoscillationextrapolationBessel function FundingThis research was sponsored by Inner Mongolia Transportation Research Project (NJ-2009-11), Liaoning Transportation Research Project (201309) and the Fundamental Research Funds for the Central Universities (DUT13LK). The supports are gratefully acknowledged.List of AbbreviationMEPDG=Mechanistic-Empirical Pavement Design GuideNCHRP=National Cooperative Highway Research ProgramFE=finite elementLET=layered elastic theoryDE=double exponential