Download or read book Impact of Reclaimed Asphalt Pavement in Asphalt Concrete Mixes Used for Airfield Pavement written by Patricia Chavez and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of reclaimed asphalt pavement (RAP) in new asphalt mixes replaces a portion of the virgin aggregate and binder, which will help with cost saving in pavement construction as well provide several environmental benefits. Currently, the Federal Aviation Administration (FAA) has no requirements and specifications for the use of RAP in accordance to the FAA Specification P401 and this research will help with the development of such specifications. The objective of this study is to create Superpave mix designs for airfields using RAP and subject them to performance related testing to provide information regarding any issues with the mix design procedure. Another objective of this project is to perform and interpret the results of laboratory testing with regard to the behavior/performance of asphalt mixes containing RAP and evaluate their suitability for use in airport pavements The experimental plan in this study included 10 different hot mix asphalt (HMA) mixes made with three different binder grades (PG 64-22, PG58-28, PG76-22PM), three RAP sources (New York, California, Alabama), and two RAP percentages (25%, 40%). A control mix with no RAP was also tested for comparison. The results of this study will be used to develop mix designs for accelerated pavement testing at the FAA National Aviation Pavement Test Facility (NAPTF) in Atlantic City, New Jersey. The results indicate that meeting the FAA's voids in mineral aggregate (VMA) requirement was problematic and while developing the mix designs with RAP the total binder content had to be reduced in order to meet the current FAA air void and VMA requirements. Performance testing showed that incorporation of RAP will improve the performance properties when compared to their respective control mixes. The statistical analysis showed that percent of RAP (by binder replacement rate) is the most significant factor affecting all performance testing and that binder grade is the least significant factor on all performance testing. It is recommended that results from this study be validated with more performance testing, including additional testing with different binder grades and performance testing for low temperature cracking. There also needs to be more testing on mix designs for airfield pavement with the addition of RAP to develop voids filled with asphalt (VFA) and dust proportion (DP) specifications.
Download or read book Recycling of Asphalt Concrete Airfield Pavement written by R. B. Brownie and published by . This book was released on 1979 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simple Performance Tester for Superpave Mix Design written by Ramon Francis Bonaquist and published by Transportation Research Board. This book was released on 2003 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global response to COVID-19 has demonstrated the importance of vigilance and preparedness for infectious diseases, particularly influenza. There is a need for more effective influenza vaccines and modern manufacturing technologies that are adaptable and scalable to meet demand during a pandemic. The rapid development of COVID-19 vaccines has demonstrated what is possible with extensive data sharing, researchers who have the necessary resources and novel technologies to conduct and apply their research, rolling review by regulators, and public-private partnerships. As demonstrated throughout the response to COVID-19, the process of research and development of novel vaccines can be significantly optimized when stakeholders are provided with the resources and technologies needed to support their response. Vaccine Research and Development to Advance Pandemic and Seasonal Influenza Preparedness and Response focuses on how to leverage the knowledge gained from the COVID-19 pandemic to optimize vaccine research and development (R&D) to support the prevention and control of seasonal and pandemic influenza. The committee's findings address four dimensions of vaccine R&D: (1) basic and translational science, (2) clinical science, (3) manufacturing science, and (4) regulatory science.
Download or read book The Use of Reclaimed Asphalt Pavement in New SUPERPAVE Asphalt Concrete Mixtures written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: While the research and development of the SUPERPAVE asphalt mixture design and analysis system did address the use of polymer modified asphalt binders in the specification of material performance properties, no recommendations or procedural guidelines were given for the use of recycled materials. The use of recycled asphalt pavements (RAP) in new paving mixtures is not an innovative idea. RAP has been called one of the most recycled materials in the world, and its use in paving mixtures has been shown to have environmental, economic and performance benefits. In this study, four different RAP stockpiles were sampled and the characteristics of each RAP material were investigated in terms of binder content, aggregate gradation and the rheologic characteristics of the reclaimed RAP binder. The reclaimed RAP binders were blended with several different virgin performance graded binders in order to determine how RAP binder concentration affected the stiffness and performance grade of the RAP -- virgin binder blends. Recommendations were made on how to select virgin binder grade andor RAP concentration combinations to fulfill a project's binder grading requirements. The effects of RAP were also investigated in terms mixture design, and recommendations were made with regards to material handling and specimen fabrication procedures. Asphalt concrete mixtures containing RAP were characterized in terms of stiffness and resistance to plastic strain using SUPERPAVE testing methods, and the results of these tests were compared to those of virgin material mixtures. Assuming a simulated pavement cross section and traffic loading, the results of this performance testing were used in performance prediction models to estimate how pavements constructed with RAP would perform compared to those made from 100% virgin materials. The predicted performance of pavements containing up to 40% RAP (by weight) was found to be similar or slightly better than that of virgin material pavements.
Download or read book Long Term Effectiveness of Recycling Agents to Improve Performance Properties of Asphalt Concrete written by Mahsa Tofighian and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recycled materials such as reclaimed asphalt pavement (RAP) have been incorporated into asphalt mixtures for many years. However, their usage has increased over time as they are seen as a way to reduce the cost of asphalt mixtures, save energy, and protect the environment. Similarly, there has been a growing focus on the utilization of recycled asphalt shingles (RAS) in asphalt mixtures, a pursuit undertaken by various state highway agencies. However, unless appropriate precautions are taken, as the proportion of RAP and RAS in the asphalt mixture is raised, the mixture becomes more brittle, leading to a higher risk of cracking and raveling in the asphalt pavement. Furthermore, the mixture becomes less workable and more challenging to compact in the field, increasing the potential for premature field failure. One strategy to incorporate more RAP and RAS into asphalt mixtures involves the use of specialized recycling agents (RAs), known as rejuvenating agents. Over time, asphalt mixtures undergo aging during construction and over the extended service life of asphalt pavements, resulting in the oxidation of the mix and the loss of a significant portion of the maltenes in the binder composition. Maltenes contribute to the softening effect of the binder, and these recycling agents, when used appropriately, are expected to compensate for this reduction in maltenes. The ultimate result of this rebalancing of components is the softening of the aged binder and an improvement in its resistance to cracking. This study investigates the long-term impact of bio-based and petroleum-based recycling agents (RA's) on recycled asphalt binders with varying levels of reclaimed asphalt pavement (RAP) and reclaimed asphalt shingles (RAS) content, specifically low (15%) and high (30%) RAP content and 0% and 5% RAS content. The rejuvenated binders underwent short-term and long-term aging through the use of a Rolling Thin Film Oven (RTFO) and Pressure Aging Vessel (PAV), respectively. The performance characteristics of these modified binders at various aging stages were assessed using a dynamic shear rheometer (DSR) and bending beam rheometer (BBR). The study revealed that all RA's used in this research maintained their effectiveness even after long-term aging, though the degree of effectiveness varied. Additionally, the results indicated that the petroleum-based RA required a higher dosage to achieve the same effect as the bio-based RA's. The findings from this research also demonstrated that when rejuvenators are added to mixtures with a high RAP content or a combination of RAP and RAS, the mixture's performance is enhanced in terms of low-temperature cracking and fatigue cracking. Nevertheless, it is crucial to extend this work to field pilot projects to ensure the effective application of these rejuvenating products.
Download or read book Impact of Reclaimed Asphalt Pavement and Recycled Asphalt Shingles on Laboratory and Field Performance of Texas Asphalt Concrete Pavements written by Berenice Salaices Gomez and published by . This book was released on 2017 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feasibility of Reclaimed Asphalt Pavement as Aggregate in Portland Cement Concrete written by Michael Berry and published by . This book was released on 2013 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research effort was focused on evaluating the feasibility of using minimally processed reclaimed asphalt pavement (RAP) as aggregate replacement in concrete pavements. This research demonstrated that concretes with up to 50 percent of the fine aggregates and 100 percent of the coarse aggregates replaced with RAP were suitable for concrete pavement. A statistical experimental design procedure (response surface methodology - RSM) was used to investigate proportioning RAP concrete mixtures to achieve desired performance criteria. Based on the results of the RSM investigation, two concrete mixtures were selected for further evaluation: a high RAP mix with fine and coarse aggregate replacement rates of 50 and 100 percent respectively, and a "high" strength mix with one half of the RAP used in the high RAP mix. Both mixes met MDT concrete pavement specifications for slump (1.5 inches), air content (6 percent), and 28-day compressive and tensile strengths (3,000 psi and 500 psi, respectively). These two concrete mixtures were subjected to a suite of mechanical and durability tests to evaluate their potential use in Montana roadways. Mechanical properties tested were compressive and tensile strength, elastic modulus, shrinkage, and creep. Durability tests included alkali-silica reactivity, absorption, abrasion, chloride permeability, freeze-thaw resistance, and scaling. Overall, both mixes performed adequately in these mechanical and durability tests, although it is important to note that the inclusion of RAP had an obvious negative impact on nearly every property tested relative to those of control mixes made with 100 percent conventional aggregates.
Download or read book Feasibility of Reclaimed Asphalt Pavement as Aggregate in Portland Cement Concrete Pavement written by Bethany Noel Bermel and published by . This book was released on 2011 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Each year, the US highway industry produces over 100 million tons of reclaimed asphalt pavement (RAP) through the rehabilitation and construction of the nation's roads. Using RAP as aggregate in Portland cement concrete pavement (PCCP) is one attractive application for a further use of this recyclable material. Earlier research has demonstrated the feasibility of creating concrete with RAP aggregate; however, prior studies focus on mechanical properties of the material. This research project will further distinguish the properties of this material and draw conclusions on the concrete's aptness for use as a pavement in Montana. This thesis encompasses the development of candidate RAP in PCCP mixtures that will subsequently move forward for a more thorough evaluation of their material properties. The mixing experiment and preliminary testing phases of this project provided information to draw a number of conclusions about the appropriateness of RAP aggregate in PCCP, including: (1) using conventional practices, PCCP containing RAP aggregate (20 percent fine and 45 percent coarse) can achieve compressive strengths in excess of 3,000-psi; (2) as the RAP replacement rate is increased, the compressive strength of the concrete decreases; (3) fine RAP aggregate appears to have a more detrimental effect on the concrete than coarse aggregate; (4) concretes with a relatively high RAP replacement rate (50 percent fine and 100 percent coarse) may be suitable for transportation applications; (5) at high RAP replacement rates, there appears to be a benefit (relative to concrete strength) in using increased replacements of both fine and coarse RAP, rather than singly replacing just one aggregate gradation; and (6) concrete containing RAP displays increased flexural strengths as compared to traditional PCCP. This material research was performed using a Design of Experiments (DOE) method. The suitability of this statistical method as a mix design development tool was characterized through several important findings, which include: (1) the DOE method was effective in distinguishing mixture behaviors; (2) mix design optimization is readily accomplished using the statistical model generated from the DOE data; and (3) variability in the concrete mixing and testing processes has a significant effect on the capabilities of the statistical model.
Download or read book The Use of Reclaimed Asphalt Pavement in New SUPERPAVE Asphalt Concrete Mixtures written by Glen Alan Malpass and published by . This book was released on 2003 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: RAP, asphalt concrete, pavements recycling.
Download or read book Recommended Use of Reclaimed Asphalt Pavement in the Superpave Mix Design Method written by Rebecca McDaniel and published by . This book was released on 2001 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Reclaimed Asphalt Pavements on Pavement Sustainability written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flexible Pavement Mixture Design Using Reclaimed Asphalt Concrete written by Bernard F. Kallas and published by . This book was released on 1984 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Asphalt Paving Technology 2011 written by Eugene L. Skok and published by DEStech Publications, Inc. This book was released on 2011-06-28 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Airfield and Highway Pavements 2021 written by Hasan Ozer and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Selected papers from the International Airfield and Highway Pavements Conference 2021, held virtually June 8-10, 2021. Sponsored by the Transportation & Development Institute of ASCE.This collection contains 36 peer-reviewed papers on pavement materials and sustainability.Topics include: laboratory and field characterization of asphalt binders; modifiers and rejuvenators; asphalt mixtures and modification; recycled and waste materials in asphalt mixtures; unbound base/subgrade materials and stabilization; pavement life-cycle management; interactions of pavements and their environment; cementitious materials characterization and concrete pavement technology; and innovative and sustainable technologies used in pavement applications. This proceedings will be of interest to engineers, designers, project/construction managers, researchers, and contractors involved in the design and construction of airfield and highway pavements.
Download or read book Bituminous Mixtures and Pavements VII written by A.F. Nikolaides and published by CRC Press. This book was released on 2019-05-24 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt: Highway engineers are facing the challenge not only to design and construct sustainable and safe pavements properly and economically. This implies a thorough understanding of materials behaviour, their appropriate use in the continuously changing environment, and implementation of constantly improved technologies and methodologies. Bituminous Mixtures and Pavements VII contains more than 100 contributions that were presented at the 7th International Conference ‘Bituminous Mixtures and Pavements’ (7ICONFBMP, Thessaloniki, Greece 12-14 June 2019). The papers cover a wide range of topics: - Bituminous binders - Aggregates, unbound layers and subgrade - Bituminous mixtures (Hot, Warm and Cold) - Pavements (Design, Construction, Maintenance, Sustainability, Energy and environment consideration) - Pavement management - Pavement recycling - Geosynthetics - Pavement assessment, surface characteristics and safety - Posters Bituminous Mixtures and Pavements VII reflects recent advances in highway materials technology and pavement engineering, and will be of interest to academics and professionals interested or involved in these areas.
Download or read book Hot mix Recycling of Asphalt Concrete Airfield Pavements written by James E. Shoenberger and published by . This book was released on 2005 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Durability of Recycled Asphalt Concrete Surface Mixes written by Osama Ahmed Abdulshafi and published by . This book was released on 1997 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
