Hot mix asphalt has various benefits such as good workability and durability. It is one of the most general materials used mixtures in road pavements. Asphalt binders can be improved by modifying them with additives. Gilsonite a natural hydrocarbon which may an additive to hot asphalt. binder modifier (wet process) mixture (dry improve properties mix. provides option rheological properties, sta...

IN T R O D U C T IO N The major material utilized in the construction of the roads, streets and highways of this country is asphalt. Of the nation’s 3.84 million miles of roads, 1.86 million are paved, hard-surfaced structures. 1.74 million or 94% of these paved roads are constructed of asphalt (Fig. 1). Likewise, within the state of Indiana, 83% or about 9300 miles of the 11,200 miles under th...

Les pŽtroles bruts contiennent de nombreux constituants Ñ dont les asphaltnes Ñ qui peuvent tre adsorbŽs sur les surfaces minŽrales et modifier leurs caractŽristiques de mouillage. Ce qui distingue les asphaltnes des autres constituants de l'huile est leur tendance ˆ s'agrŽger et mme ˆ se sŽparer du pŽtrole en rŽaction ˆ des modifications du pouvoir solvant du pŽtrole. Du fait qu'ils change...

Putting Research Into Practice Page 10 The National Center for Asphalt Technology (NCAT) has just completed a National Cooperative Highway Research Program (NCHRP) Project: NCHRP 9-11, “Segregation in Hot Mix Asphalt Pavements.” Dr. Mary Stroup-Gardiner was the principal investigator on this project. Segregation has historically been defined to mean localized areas of coarse materials in some a...

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...

Using a rejuvenator to improve the performance of asphalt pavement is an effective and economic way of hot asphalt recycling. This research analyzes the rejuvenating effect on aged asphalt by means of a Mortar Transfer Ratio (MTR) test, which concerns the ratio of asphalt mortar that moves from recycled aggregates (RAP aggregates) to fresh added aggregates when aged asphalt is treated with a re...

Molecular dynamics simulation was used to calculate rotational relaxation time, diffusion coefficient, and zero-shear viscosity for a pure aromatic compound (naphthalene) and for aromatic and aliphatic components in model asphalt systems over a temperature range of 298-443 K. The model asphalt systems were chosen previously to represent real asphalt. Green-Kubo and Einstein methods were used to...

Low-temperature cracking is one of the most common road pavement distress types in Poland. While bitumen performance can be evaluated in detail using bending beam rheometer (BBR) or dynamic shear rheometer (DSR) tests, none of the normalized test methods gives a comprehensive representation of low-temperature performance of the asphalt mixtures. This article presents the Bending Beam Creep test...

Over the last decade, unexpected and sudden pavement failures have occurred in several provinces in South Korea. Some of these failures remain unexplained, further illustrating the gaps in our knowledge about binder chemistry. To prevent premature pavement distress and enhance road performance, it is imperative to provide an adequate characterization of asphalt. For this purpose, the current re...

The Fremont Bridge is steel tied arch bridge over the Willamette River in Portland, Oregon. It carries traffic on Interstate 405 and US Highway 30 between downtown and north Portland. . The bridge was constructed in 1973, and the paving on the original steel deck consisted of epoxy asphalt concrete followed by an asphalt concrete overlay. The pavement performed for nearly 40 years before it nee...