This paper presents the results of a constructability and productivity analysis for the Caltrans Long Life Asphalt Concrete Pavement Rehabilitation Strategies (LLACPRS). With the assistance of California asphalt concrete paving contractors, the analysis explored the effects on construction productivity of rehabilitation materials, design strategy (crack seat and overlay, full-depth replacement)...

this paper presents the effects of different amounts of reclaimed asphalt on fatigue life of asphalt mixtures. central composite method was used to design of experiments based on response surface method (rsm). binder type (pen 60/70 and pen 85/100), reclaimed asphalt pavement (rap) content (25, 50 and 75%) and loading strain (150, 250 and 350 micro strain) were selected as independent variables...

Noise is defined as a loud sound of any sort that is disagreeable or unwanted. Throughout the ages of civilized history, noise has been an annoying irritant to mankind. In recent years the noise level of freeways in urban and suburban areas in the United States has increased perceptibly as freeway traffic has increased and more people are living closer to freeways. To reduce such a noisy irrita...

Remote sensing may offer quick and economical methods of surveying road centerline geometry and condition. This research uses a combination of 4 m, 224-band AVIRIS hyperspectral imagery, and about 6000 field-gathered spectra, to develop a spectral library of urban materials. It attempts to extract roads of various types, and investigates the spectral signatures associated with different qualiti...

A review of several past studies clearly shows the effect of reduced air voids on improved fatigue and rutting performance of asphalt mixtures, both in the laboratory and field. Depending on mix type and experiment (which included constant-stress bending beam fatigue testing and field results from WesTrack), fatigue performance improved between 8.2 and 43.8% with a 1% decrease in air voids. Lik...

The National Center for Asphalt Technology (NCAT) has undertaken a wide range of hot mix asphalt (HMA) related research projects. These projects have been funded by various agencies such as the National Cooperative Highway Research Program (NCHRP) of the Transportation Research Board, the Federal Highway Administration (FHWA), the Alabama Department of Transportation, the South Carolina Departm...

Background In the early 1970s, due to concern over asphalt cement supply issues and an anticipated over abundance of elemental sulfur, many organizations Société Nationale des Pétroles d’Aquitaine (SNPA), Gulf Oil of Canada, Sulfur Development Institute of Canada (SUDIC), Texas Chemical Company, U.S. Bureau of Mines, and the Texas Transportation Institute) began to evaluate the potential for su...

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...