in this study an empirical model which can be used to predict the rutting parameter (g*/sinδ) for neat and powder rubber modified bitumen describes. the model was developed using 36 unique powder rubber modified bitumen combinations, rubber concentrations were varied at 5% intervals between 5 and 20%. the effects of powder rubber particle size on model accuracy were also studied ultimately a mo...

Cold-applied asphalt mixtures are often used for pavement repair, primarily because of the small quantities involved and/or the unavailability of hotmixed asphalt. These cold-applied mixtures have poorer rutting resistance than hot mix asphalt because additives, often solvent, are required to provide adequate workability for them to be placed at ambient temperatures. This study primarily evalua...

The effect of the Superpave defined restricted zone on HMA rutting performance was evaluated. One gradation that violated the restricted zone (TRZ) and two gradations that did not violate the restricted zone (BRZ and ARZ) were evaluated. Mixes evaluated represented a range of maximum aggregate sizes (MAS), design traffic levels, and aggregate types. Three laboratory tests, Asphalt Pavement Anal...

In sexually dimorphic ungulates, male reproductive success depends on fighting with other males for access to females during a brief rutting season. Large body size is necessary for success in intrasexual competition, and a few large-sized males are often able to monopolize access to female groups. Earlier studies have reported that reproductive effort increases with age until prime-age is reac...

Over the past twenty years; road traffic (both passenger and freight) has grown significantly in Pakistan. Higher axle loads and repetitions have resulted in premature rutting of flexible pavements. Rutting, in the form of shear flow is a typical distress that mainly attributed to increased tire pressure, high temperature and heavy axle loads. Consequently, National Highway Authority (NHA), Pak...

In this investigation, rheological properties of three different polymer-modified bitumen compounds containing recycled polyethylene terephthalate (R-PET), crumb rubber (CR) and poly (styrene-butadiene-styrene) (SBS) are evaluated and compared. The modified samples were tested by a dynamic shear rheometer (DSR) where complex modulus (G*), phase angle (δ) and rutting resistance (G*/Sinδ) of spec...

The National Airport Pavement Test Facility (NAPTF) is a state-of-the-art full-scale test facility operated by the U.S. Federal Aviation Administration (FAA). The NAPTF is located at the William J. Hughes Technical Center near Atlantic City, New Jersey and it provides high quality, accelerated test data from rigid and flexible pavements subjected to simulated aircraft traffic. During the first ...

Copper slag (CS) is an abrasive blasting grit made of granulated slag from metal smelting processes. As copper slags are known to be waste material and cause a lot of environmental problems, it would be a good idea to use them in different sections of industry such as pavement construction. On the other hand, in order to save energy and reduce the amount of pollutants re...

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...

In support of the initiatives for implementing the new MechanisticEmpirical Pavement Design Guide (MEPDG) in Iowa, a preliminary sensitivity study was undertaken to assess the comparative effect of design input parameters pertaining to material properties, traffic and climate on performance of two existing flexible pavements in Iowa with relatively thick Asphalt Concrete (AC) layers. A total of...