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...

Confocal Laser Scanning Microscopy (CLSM) has gathered interesting new results regarding the microstructure of bitumina as part of a comprehensive study on bitumen and asphalt concrete. Compared to normal fluorescence microscopy, the CLSM technique has been proven to be the method of choice for bitumen. The main advantage is a much stronger fluorescence signal due to the higher intensity of the...

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...

The weak connection performances between the waterproof adhesive layer, bridge deck, and asphalt pavement are important factors that cause deck slippage upheaval affect safety durability of bridge. In this paper, styrene-butadiene-styrene- (SBS-) modified asphalt, SBS-emulsified rubber-modified AMP-100 materials selected to study performance layer in seasonal frozen region. shear strength bond ...

The use of polymer in hot mix asphalt production has remarkably in recent decades. Destruction due to moisture in hot mix asphalt is of basic matters about flexible pavement durability. In recent decades different ways have been used to evaluate moisture Sensitivity of HMA which some of them are simple with low cost and some are complicated with more reliable results. In this research the effec...

In order to study the self-healing performance of macroscopic fractures asphalt mixtures, semicircular bending (SCB) tests were used test 90# base SBS (Styrene–Butadiene–Styrene) modified and + CR (Chloroprene Rubber) composite mixtures. The F-H-F (the mixture specimen was fatigued for a certain number times, then healed under conditions, until destroyed) carried out, fatigue life recovery rate...

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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...