In road paving industry, asphalt emulsion is used for cold mix application such as chip seal, slurry seal, microsurfacing, cold recycled mixture and etc. Asphalt emulsion has several advantages compared to normal asphalt such as eco-friendly, easy to handle at ambient temperature and energy saving material because it does not need any heating process in its application. The history of asphalt e...

Based on the analysis of the mechanism and hazards of asphalt fume, by adding two fume suppressant Mg(OH)2 and Al(OH)3 and two viscosity reducers Sasobit and ROADBIT-BPL, the paper optimized the mixture ratio for road use, and prepared the environment-friendly fume-suppression asphalt, and then conducted the performance tests to identify the optimum dosage. The results show that: the fume amoun...

BACKGROUND Asphalt workers are exposed to polyaromatic hydrocarbons (PAHs) from hot mix asphalt via both inhalation and dermal absorption. The use of crumb rubber modified (CRM) asphalt may result in higher exposure to PAHs and more adverse effects. Our aim is to assess occupational exposure to PAHs from conventional and CRM asphalt paving by measuring PAH metabolites in urine, and to investiga...

This study investigated the effect of high asphalt binder replacement for a low N-design asphalt mixture including RAP and RAS on performance indicators such as permanent deformation, fracture, fatigue potentials, and stiffness, was studied. An experimental program included complex modulus, fracture, overlay reflective cracking resistance, wheel track permanent deformations, and push-pull fatig...

Using Reclaimed Asphalt Pavement (RAP) in asphalt mixes has become a common practice in many countries as experience indicated that the recycling of asphalt pavements is very advantageous from different perspectives. Some of the advantages of utilizing RAP include conservation of asphalt and aggregate resources, conservation of energy, and reduction in life-cycle cost. In this study, the suitab...

asphalt modification/reinforcement has received considerable attention as viable solutions to enhance flexible pavement performance. this is mainly prompted by the unsatisfactory performance of traditional road materials exposed to dramatic increases and changes in traffic patterns. this paper presents the evaluation of fatigue behaviour of nano reinforced stone mastic asphalt mixtures. fatigue...

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 ...

Using nano-technology materials in the asphalt pavement industry is new compared with Portland cement concrete. The main objective of this study is to investigate the effects of nano-silica modification on some properties of a penetration grade asphalt cement and a typical asphalt concrete. 60/70 penetration grade bitumen was modified with different percentages of nano-silica (i.e. 1, 3 and 5%,...

The sustainability movement has established a firm foothold in the Civil Engineering profession. The use of recycled asphalt shingles (RAS) is the latest development in the world of asphalt pavement sustainability. The relative abundance of tear-off shingles and their high asphalt content is driving RAS usage in highway and airfield pavements. However, the ultimate objective of any pavement sys...

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...