Why it matters
Asphalt concrete, the ordinary asphalt, is a composite material: mineral aggregates (78-87% of the volume) bound together by bitumen, which, although only 4-8% by weight, governs almost all of its mechanical behaviour. Bitumen is highly temperature-sensitive: below -20°C the material is elastic-brittle, between -20°C and 10°C it becomes viscoelastic, between 40°C and 60°C viscoplastic, and above 100°C it behaves almost like a fluid. The project focuses on the viscoelastic regime, modelled with the modified Huet-Sayegh rheological model (springs and parabolic dampers that let you tune the behaviour continuously between purely elastic and purely viscous), calibrated on laboratory tests from the literature and then applied to realistic meso-scale geometries, with the aggregates explicitly represented in the specimen.
What you'll do
- Calibrate the parameters of the modified Huet-Sayegh viscoelastic model on laboratory tests from the literature.
- Generate the meso-scale specimen geometry, with the aggregate arrangement obtained through randomisation algorithms consistent with the grading curve of the material.
- Simulate loading-unloading cycles on the meso-scale model and compare its response with the one expected from the real material.
Prerequisites
- Knowledge of FEM simulations from the Computational Mechanics course (or equivalent).
Tools
- Abaqus, for meso-scale FEM modelling and for calibrating the viscoelastic model.
Supervisor
Prof. Gianluca Mazzucco · gianluca.mazzucco@unipd.it