MnLayer: High-performance layered elastic analysis program

Layered elastic theory (LET) has been used successfully for many years in the design and analysis of asphalt pavements. An attractive feature of this approach is its ability to represent the layered-pavement structure with variable interface conditions between consecutive layers. Several computer programs (BISAR, WESLEA, and JULEA) for the analysis of pavement systems were developed on the basis of LET. A new Mechanistic-Empirical Pavement Design Guide (MEPDG) procedure was recently developed by NCHRP under AASHTO sponsorship. It requires that layered elastic analysis be performed more than 1,000 times for a single design simulation of a flexible (asphalt) pavement, which makes the flexible design process extremely time consuming. An important step toward reducing the time needed to use the MEPDG software is improvement in the computational efficiency of the layered elastic analysis. In this paper, a new layered elastic analysis program, MnLayer, is presented. Several improvements in the numerical evaluation of the inverse Hankel transform of the layered elastic solutions were implemented into the program. A comprehensive comparison of MnLayer with two widely used layered elastic analysis programs demonstrated that MnLayer's accuracy matches or exceeds the accuracy of these other programs while its computational time is as little as 1/20 of theirs.