Porous asphalt pavements are environmentally friendly permeable road pavements. There is a need to improve the strength performance of porous mixtures. Waste Ethylene Propylene Diene Monomer (EPDM) rubber modification mixtures investigated in this study. The mixture was initially designed for selected mix aggregate gradation. EPDM scraps were replaced with filler materials at rate 2 % and 4 tot...

This work aims to improve the rutting and fatigue cracking resistance of asphalt binders using selected nanoor micro-sized materials and to shed light on the microstructure changes induced by such modification to asphalt binders. The four modifiers (Nanomer I.44P, carbon microfiber, non-modified nanoclay and polymer modified nanoclay) were added into the control asphalt binder (PG 58-34). The S...

This paper characterizes the effects of artificial short term aging in the laboratory on the rheological properties of virgin 80/100 penetration grade asphalt binder. After several years in service, asphalt mixture started to deteriorate due to aging. Aging is a complex physico-chemical phenomenon that influences asphalt binder rheological properties causing a deterioration in asphalt mixture p...

The incremental health risk for workers of the road-paving sector using rubberized asphalt was assessed based on the outcome of monitoring campaigns carried out during paving operations where both rubberized and standard asphalt were used. The exposure of workers to Polycyclic Aromatic Hydrocarbons (PAHs) released in the asphalt fumes were measured by means of personal samplers and dermal sampl...

Standard asphalt mixtures for road infrastructures consist of natural aggregate and bitumen. A number of research efforts have successfully investigated the possibility of replacing the conventional aggregate skeleton with industrial by-products such as slag originating from steel production process. However, little is known on the effect of steel slag on the mixtures functional performance and...

This study presents micromechanical finite-element FE and discrete-element DE models for the prediction of viscoelastic creep stiffness of asphalt mixture. Asphalt mixture is composed of graded aggregates bound with mastic asphalt mixed with fines and fine aggregates and air voids. The two-dimensional 2D microstructure of asphalt mixture was obtained by optically scanning the smoothly sawn surf...

Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the ...

Asphalt concrete is widely known to be a self-healing material, by repeated loading the micro-cracks have appearing and disappeared when both faces of fissure touch. This process applied until crack completely gone material regains its prior resistance. In this study, two strategies are presented boost healing rate in porous asphalt, one them induction heating. method used mixing 1.1% steel woo...

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The thermodynamic behavior of asphalt mixtures is critical to the engineers since it directly relates to the damage in asphalt mixtures. However, most of the current research of the freeze-thaw damage of asphalt mixtures is focused on the bulk body from the macroscale and lacks a fundamental understanding of the thermodynamic behaviors of asphalt mixtures from the microscale perspective. In thi...