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To give engineers involved in planning and designing of asphalt pavements a more accurate prediction of crack initiation and propagation, theory-based models need to be developed to connect the loading conditions and fracture mechanisms present in laboratory tests and under traffic loading. The aim of this study is to develop a technical basis for the simulation of fracture behavior of asphalt pavements. The cohesive zone model (CZM) approach was applied in the commercial FE software ABAQUS to analyze crack propagation in asphalt layers. The CZM developed from the asphalt mixtures in this study can be used to simulate the fracture behavior of pavements and further optimize both the structure and the materials. The investigations demonstrated that the remaining service life of asphalt pavements under cyclic load after the initial onset of macro-cracks can be predicted. The developed CZM can, therefore, usefully supplement conventional design methods by improving the accuracy of the predicted stress states and by increasing the quality, efficiency, and safety of mechanical design methods by using this more realistic modeling approach.

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To combine the advantages of microstructural finite element (FE) models of asphalt composites and macrostructural FE models of pavement structures subjected to rolling tire load, this article introduces a novel consistent simulation chain. Starting with experimental tests of asphalt mortar, an existing microstructural FE model of a Stone Mastic Asphalt, which contains coarse aggregates, asphalt mortar and air voids, is parameterized and validated. The microstructural model is then applied to identify macroscopic (homogenized) material properties of the asphalt mixture that are used in FE computations of two pavement structures under rolling tire load. The macrostructural pavement computations are evaluated by a new macro-micro-interface that generates realistic time-dependent displacement boundary conditions representing the rolling tire loading conditions for the microstructural model. A verification and exemplary microstructural computations at rolling tire load boundary conditions show that the introduced simulation chain allows for the investigation of the processes, stresses, and strains inside the asphalt composite at realistic loading conditions. Results can, for example, be used to improve the experimental tests on the component level as well as to gain a better understanding of the interacting processes in asphalt mixtures under rolling tire load. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

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