Simulation of mastic erosion from open-graded asphalt mixes using a hybrid Lagrangian-Eulerian finite element approach

This paper presents a numerical approach for the modeling of water flow induced mastic erosion from a permeable asphalt mix and is part of an ongoing effort to model moisture-induced damage in asphalt mixes. Due to the complex composite structure of asphalt mixtures, moisture can infiltrate in various ways into the components and have an adverse effect on its mechanical performance. Depending on the gradation of the asphalt aggregates and the mixing procedure, asphalt structures with a variable permeability may result. Open-graded asphalt mixes are designed with a high interconnected air void content to serve as a drainage layer on the pavement and are therefore frequently exposed to fast water flow fields. This paper demonstrates a numerical procedure to simulate the effects of an advectiondominated transport process on the mastic concentration within an open-graded asphalt mix. A Hybrid Lagrangian-Eulerian finite element approach is implemented with a single step reverse particle tracking scheme to solve the Lagrangian concentration tensor. The procedure is validated with two analytical studies and a numerical simulation is shown for the advective transport of mastic from an asphaltic system.