The dynamic modulus is the main input material property of asphalt mixtures for the modern mechanistic-empirical asphalt pavement design methods. The dynamic modulus is determined in laboratory by different procedures but in all cases, they require sophisticated equipment and well-trained personnel. When these experimental results are not available, they could be estimated using different predi...

This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt materia...

The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technol...

Flow number of asphalt–aggregate mixtures as an explanatory factor has been proposed in order to assess the rutting potential of asphalt mixtures. This study proposes a multiple–kernel based support vector machine (MK–SVM) approach for modeling of flow number of asphalt mixtures. The MK–SVM approach consists of weighted least squares–support vector machine (WLS–SVM) integrating two kernel funct...

In this research, the efficiency of Recycled Glass Powder (RGP) is evaluated for improvement of polymer-modified bitumen and asphalt mixture performance. An extensive laboratory programm was undertaken for polymer-modified bitumen including Crumb Rubber (CR), Styrene Butadiene Styrene (SBS) and Styrene Butadiene Rubber (SBR). Rheological and mechanical proper...

This study was conducted in order to evaluate the effects of long term ageing on toughness and resilient modulus of asphalt concrete mixtures containing Electric Arc and Basic Oxygen Furnace steel slags. After initial evaluation of the properties of steel slags using X-ray Diffraction and Scanning Electric Microscope, eleven sets of laboratory mixtures were prepared. Each set was treated replac...

Semi-Circular Bending (SCB) Test is a fast and accurate three-point bending test, which was originally used in rock mechanics. SCB test is going to be an accepted test method for asphalt concrete pavements. Different asphalt-mixture property-values such as tensile strength, stress intensity factor and fatigue can be obtained by this test. In this study, static and dynamic tests including SCB te...

The National Center for Asphalt Technology (NCAT) completed a roundrobin study in March to determine the accuracy and precision of the NCAT asphalt content tester. The Center has conducted research since 1990 to develop this test method for determining asphalt content of hot mix asphalt (HMA) mixtures by ignition (See the fall, 1994, issue of Asphalt Technology News). In the ignition method, a ...

pavement permanent deformations due to lack of shear strength in mixture are a major reason of rutting. any simple test to determine mixtures resistance to permanent deformation isn’t distinguished in the 1st level of superpave mix design method and prevalent methods for evaluating mixture rut resistance are expensive and time-consuming. two aggregate types, gradations, asphalt cements and fill...

Previous research has shown that composite shape-stabilized phase change material (CPCM) has a remarkable capacity for thermal storage and stabilization, and it can be directly applied to highway construction without leakage. However, recent studies on temperature changing behaviors of CPCM and asphalt mixture cannot intuitively reflect the thermoregulation mechanism and efficiency of CPCM on a...