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 quantifies the potential environmental benefits associated with incorporation of industrial by-products and recycled materials combined warm mix asphalt (WMA) additives in wearing course mixtures for pavement construction. An electric arc furnace (EAF) steel slag-based three incorporating slag fractionated reclaimed (RA) varying contents (i.e. 25, 40, 50%) were analyzed comparatively...

Fatigue cracking is an essential problem of asphalt concrete that contributes to pavement damage. Although stone matrix asphalt (SMA) has significantly provided resistance to rutting failure, its resistance to fatigue failure is yet to be fully addressed. The aim of this study is to evaluate the effect of crumb rubber modifier (CRM) on stiffness and fatigue properties of SMA mixtures at optimum...

Emulsion aggregate mixtures (EAMs) are blends stabilized with an asphalt emulsion for pavement base layer applications. These typically prepared using crushed aggregates and designed primarily a tensile strength-based criteria. Advances in granular material testing technologies have led to the development of advanced resilient response characterization devices such as University Illinois FastCe...

The use of recycled materials in pavement construction has seen, over the years, a significant increase closely associated with substantial economic and environmental benefits. During the past decades, many transportation agencies have evaluated the effect of adding Reclaimed Asphalt Pavement (RAP), and, more recently, Recycled Asphalt Shingles (RAS) on the performance of asphalt pavement, whil...

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 ...

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...

Construction of flexible pavements with hot mix asphalt (HMA) mixtures consumes huge energy which impacts the resources and the environment of the world. Warm Mix Asphalt (WMA) is an effective alternative as they produced with lower mixing and compaction temperature than those used in HMA production. This technology decreases energy consumption, saves money, and reducing the environmental pollu...