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...

Design frequently involves a series of tradeoffs to obtain the “optimal” solution to a design problem. Green roofs have many different characteristics based on a variety of variables. Designers typically weigh the impacts of these characteristics in an implicit process based on intuition or past experience. But since vegetated roofing is a relatively complex and comparatively new technology to ...

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...

This paper presents an overview of observed distresses on low slope roofing systems collected for the Building Envelope Life Cycle Asset Management (BELCAM) project. The data include over 14,000 visible distresses from 600 roofs from seven different climatic regions across Canada. The distresses encountered for built up roofs, modified bituminous roofs and a limited number of single-ply roofing...

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...