Modelling and Simulation of Asphalt

Abstract

Increasing requirements on the durability of road pavements demand the conception of innovative asphalt types. Particularly the stability under load needs improvement in order to prevent rutting. Since the load bearing capabilities of asphalt are mainly governed by the granular lattice and the binder that glues the rocks together, simulation based approaches that aim on supporting R&D in road engineering must capture the granulometry of the material. A Voronoi tesselation based description of the structure is proposed that enables the separate modelling of grains and binder as continuous materials and attempts to accurately reproduce those features. First, a neat Voronoi tesselation is created within the modelling domain. These irregular convex polyhedra representing the grains are subsequently subject to a shrinking process and further modified to accurately represent the granulometric distribution of real asphalt types. Now, the space between the grains can be used for a volumetric representation of the binder. Full-field strain measurements during the indirect tensile test of mastic asphalt, stone mastic asphalt and asphalt concrete have been performed for validation of the approach.

Microstructural Modeling and Strengthening Mechanism of TiB/Ti-6Al-4V Discontinuously-Reinforced Titanium Matrix Composite

“…The shape, size, and spatial distribution of the Phase-II region in the DRTMC microstructure exhibit a certain degree of randomness. In order to provide an improved representation of the DRTMC microstructure, a realistic modeling method was developed in our work, based on the algorithm of shrinking the Voronoi cells (Thiessen polygons) [ 14 ], which was developed by scholars [ 15 , 16 ]. By means of Fortran programming, the network-like microstructure model containing Phase-I and Phase-II can be generated automatically, and finally transferred to form a 2D RVE finite element model for mechanical simulation.…”