Print Email Facebook Twitter Microstructural Changes in Bitumen at the onset of Damage-healing Title Microstructural Changes in Bitumen at the onset of Damage-healing Author Nahar, S.N. (TU Delft Pavement Engineering) Schmets, A.J.M. (TU Delft Pavement Engineering) Kasbergen, C. (TU Delft Pavement Engineering) Schitter, G (Technische Universität Wien) Scarpas, Athanasios (TU Delft Pavement Engineering) Date 2016-06 Abstract Self-healing of bitumen is a property that positively contributes to the sustainability, maintenance requirements and cost effectiveness of asphalt pavements. Ideally one would like to design an asphalt mix with a well-defined healing potential. Although substantial research efforts have been dedicated to the healing mechanism in bitumen, complete understanding of the fundamental mechanisms that govern the property of healing is still lacking. Here we investigate the manifestation of damage and healing of bitumen at the microstructural level. Three distinct bitumen grades are subjected to mechanical loading conditions, and the damage is investigated at the microstructural level by atomic force microscopy combined with finite element simulations. One of the bituminous phases appears to display visible signs of cracks, which are found to (partly) disappear at moderate temperature changes. Simulations of mechanical loading of experimentally derived finite element meshes are corresponding well with these experimental observations. Moreover, the simulations provide a measure of mechanical response, i.e. stiffness, of the material as a function of strain level. From this it is found that the microstructural cracks lead to diminished structural response properties, whereas after healing these properties are partly recovered. The experimental observations, together with the simulations, support earlier ideas that relate the phenomenon of self-healing in bitumen to their rheological property of thixotropy. Moreover, the work presented hints that the property of self-healing is governed by processes at the microstructural length scale. Subject BitumenAtomic Force Microscopy (AFM)micro-crackmicrostructurethixotropy To reference this document use: http://resolver.tudelft.nl/uuid:359eb283-4e67-4daf-8907-3057bdb70067 Source CROW InfraDagen 2016 Event CROW InfraDagen 2016, 2016-06-22 → 2016-06-23, Papendal, Arnhen, Netherlands Part of collection Institutional Repository Document type conference paper Rights © 2016 S.N. Nahar, A.J.M. Schmets, C. Kasbergen, G Schitter, Athanasios Scarpas Files PDF 95_Microstructural_Change ... ealing.pdf 1.4 MB Close viewer /islandora/object/uuid:359eb283-4e67-4daf-8907-3057bdb70067/datastream/OBJ/view