Phase-Separation Characteristics of Bitumen and their Relation to Damage-Healing

During the service life of flexible asphalt pavements, asphalt concrete degrades due to traffic loading and environmental conditions like temperature, rain, oxidation, ultraviolet-radiation from the sun. All these environmental factors have adverse effects on the performance of bitumen, which is the binder of asphalt concrete. They are known to...

Hot Mix Asphalt Recycling: Practices and Principles

Hot mix asphalt recycling has become common practice all over the world since the 1970s because of the crisis in oil prices. In the Netherlands, hot recycling has advanced to such an extent that in most of the mixtures more than 50% of reclaimed asphalt (RA) is allowed. These mixtures with such a high RA content are produced in a batch plant to...

Chemomechanics of Damage Accumulation and Damage-Recovery Healing in Bituminous Asphalt Binders

As a contribution to the development of mutli-scale multi-physics approaches to modelling pavement performance, the present thesis considers the topic of damage accumulation accompanied by damage recover self-healing of the bituminous asphalt phase of pavement systems. It is found insightful that by adopting Hveem’s [1943] concept of attributing...

Interfacial interactions and mass transfer at the interfacial region of bituminous hydrocarbon mixtures

The adhesion between bitumen and aggregate is a complex process with numerous of variables. To improve the understanding of the bond between bitumen and aggregates in road applications, this research focuses on preferential adsorption, which is one aspect of bitumen-aggregate adhesion. The main objective is to find out whether there is...

Self-healing bitumen by microcapsules containing rejuvenator

Preservation and renovation bitumen of pavement is a big problem for the whole world. Traditionally, application rejuvenators is the only one method that can restore the original properties of the pavements. However, some puzzles still restrict its successful usage. Microencapsulation is a promising method to apply rejuvenator in bitumen. These...

Temperature induced healing in strained bituminous materials observed by atomic force microscopy

Bitumen is the binder in the composite material named asphalt concrete. Under cyclic mechanical loading of traffic passing over the pavement, eventually damage will initiate in the pavement, leading to eventual structural failure. This damaging process is accelerated by time dependent change of the mechanical properties of asphalt concrete due...

Microstructural self-healing of bituminous materials: Combined experimental and numerical study

Bituminous materials form a class of materials that possess the intrinsic ability to selfheal. This self-healing capability is evidenced by the observation that the service life of these materials ‘in the field’ exceeds the service life as predicted by standard mechanical laboratory tests. This mismatch between laboratory prediction and field...

The Influence of Ageing on the Fatigue and Healing Properties of Bituminous Mortars

For asphalt pavement design in Belgium, healing is taken into account as a standard shift factor, representing the effect of rest periods between loadings of traffic. Because nowadays Reclaimed Asphalt Aggregate (RA) is widely used in hot mixtures, a new validation of the healing factor is needed. Given the lack of test results and a standard...

Evaluating Self Healing Capability of Bituminous Mastics

The self-healing capability of bituminous materials has been known for many years. Researches were mostly focused on the self healing behaviour during load repetitions. The tests are either time consuming and/or complex. In this paper, a simple self healing test procedure is presented combining the fracture-healing-re-fracture test (FHR) with...

Self healing of road-use bituminous materials: Mechanical characterization and its modelling (abstract)