rutting of hot mix asphalt pavements due to increased number of heavy vehicles, especially in tropical regions, causes several performance problems. large stone asphalt mixtures have more stiffness and shear resistance and so more rutting resistance compared to conventional mixtures. hence, using these mixtures in thick layers of hot mix asphalt pavements at tropical regions could be an appropr...

The use of reclaimed asphalt pavement (RA) in new asphalt pavements can provide important economical savings, while reducing the negative environmental impact. The European research project PARAMIX aims to improve the techniques for hot mix recycling in plant and cold mix in situ recycling, so as to increase the amount of reclaimed asphalt and develop competitive road pavement rehabilitation te...

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...

In addition to lower emissions warm mix asphalt has several advantages over hot mix asphalt such as fuel energy savings, decreased binder aging and an extended paving season (Photo courtesy: Matthew Corrigan, FHWA) The National Center for Asphalt Technology (NCAT) is evaluating warm mix asphalt (WMA) technologies. WMA technology allows the mixing, lay down, and compaction of asphalt mixes at si...

The quality of hot mix asphalt is affected by the quality and consistency of input aggregates and the control of the production process. To improve the quality of hot mix asphalt, both the aggregates gradation and the process variables must be considered. Current practice involves taking samples from actual production and analyzing them in the lab. The entire process can take two hours, which, ...

To determine the behavior of hot mix asphalt including different penetration grade bitumen has been a major subject of paving engineering. In this study the effects of different penetration grade binders on the mechanical properties of hot mix asphalt were investigated with four different tests. The specimens prepared with AC-5, AC-10, AC-20 and SBS modified AC-10. The stiffness modulus, creep ...

The environmental impacts of producing asphalt mixtures with different percentages of asphalt binder replacement (ABR) are assessed using the technique of life cycle assessment (LCA). In this paper, only the material production phase of the pavement life cycle is considered. To improve the quality of the LCA, a regionalized life cycle inventory (LCI) database for the Northern Illinois region is...

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...

Hot-mix asphalt (HMA) surfaces comprise about 90% of the highways and roads in the U.S. Highways and are typically engineered to last 15 years or more, but many have been failing early due to potholes, cracks, raveling, and other problems. This premature road failure unnecessarily wastes millions of taxpayer dollars every year. This paper describes a series of research studies that were conduct...