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...

seismic behavior of a rockfill dam with asphalt-concrete core has been studied utilizing numerical models with material parameters determined by laboratory tests. the case study selected for these analyses, is the meyjaran asphalt core dam, recently constructed in northern iran, with 60 m height and 180 m crest length. the numerical analyses have been performed using a nonlinear three dimension...

Due to the high price of crude oil, and consequently asphalt binder, the application of Reclaimed Asphalt Pavement (RAP) in pavement technology is widely considered. The present paper is the result of a laboratory research which was carried out to investigate the effects of adding a rejuvenating agent to Hot Mix Asphalt (HMA) with RAP. To this end, test samples comprised of Aged Asphalt Binder ...

Workers in the road construction industry include asphalt plant, ground construction, and road paving workers. These individuals can be exposed to a wide range of potentially hazardous substances. A summary of levels of exposure to different substances measured during road construction is presented. In modern road paving, workers typically are exposed to 0.1 to 2 mg/m3 of bitumen fume, which in...

This study reports the simulation of a photocatalytic system process and the photocatalytic property of self-cleaning asphalt concrete (SCAC) with four typical asphalt mixtures. A photocatalytic system was simulated based on the pollutant concentration data, which were collected on three types of city roads. Two photocatalytic indexes were proposed to evaluate the photocatalytic property of sel...

This project documents the impact of a porous asphalt overlay on the quality of highway stormwater runoff. A porous asphalt overlay, also known as a permeable friction course (PFC) or open graded friction course (OGFC), is a layer of porous asphalt approximately 50 mm thick which is often applied on top of conventional asphalt highways to enhance safety and reduce noise. The quality of stormwat...