Download or read book Aging Characterization of Foamed Warm Mix Asphalt written by Mir Shahnewaz Arefin and published by . This book was released on 2015 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluated the aging characteristic of foamed warm mix asphalt (WMA) produced by water injection in comparison to traditional hot mix asphalt (HMA). Four types of asphalt binders (PG 64-22, PG 64-28, PG 70-22, PG 76-22) were used in the preparation of the foamed WMA and HMA mixtures. All mixtures were prepared using limestone aggregates with a nominal maximum aggregate size (NMAS) of 12.5 mm that met the Ohio Department of Transportation (ODOT) Construction and Material Specifications (C&MS) for Item 442 (Superpave Asphalt Concrete).The short-term and long-term aging of the asphalt binders were simulated using the rolling thin film oven (RTFO) and the pressure aging vessel (PAV), respectively, while the short-term and long-term aging of the laboratory-prepared asphalt mixtures were simulated according to AASHTO R 30 (Mixture Conditioning of Hot Mix Asphalt).The dynamic shear rheometer (DSR) was used to characterize the viscoelastic behavior of the unaged, RTFO-aged, and PAV-aged asphalt binders, while the dynamic modulus (lE*l) test was used to characterize the viscoelastic behavior of the short-term and long-term aged foamed WMA and HMA mixtures.In addition, the mechanistic-empirical pavement design guide (MEPDG) global aging model was used to predict the effect of aging on the dynamic modulus (lE*l) of foamed WMA and HMA mixtures, and the MEPDG global aging model predictions were compared to dynamic modulus (lE*l) test results obtained in the laboratory for both asphalt mixtures. By comparing the DSR test results following RTFO and PAV to those obtained for the unaged asphalt binders, it was observed that PG 64-22 was the least susceptible to aging followed by PG 70-22, PG 76-22, and PG 64-28. Similar trends were also observed from the dynamic modulus test, where little difference was noticed between the short-term and long-term aged specimens prepared using PG 64-22 for both foamed WMA and HMA mixtures.The dynamic modulus test results also revealed slightly lower lE*l values for foamed WMA mixtures in comparison to traditional HMA mixtures. This indicates that foamed WMA mixtures are slightly more susceptible to rutting than HMA mixtures. However, by comparing the dynamic modulus of the long-term aged specimens to the short-term aged specimens, it was observed that the increase in stiffness for the foamed WMA mixtures was less than that for the traditional HMA mixtures. This indicates that foamed WMA mixtures are less susceptible to aging and subsequently fatigue cracking than HMA mixtures.Finally, by the comparing the MEPDG global aging model predictions to the dynamic modulus test results for both foamed WMA and HMA mixtures, it was observed that the MEPDG global aging model provided more reasonable predictions, especially at higher frequencies, but overestimated or underestimated the dynamic modulus at lower frequencies. This was observed for both foamed WMA and HMA mixtures, which suggests that this model can be used for both types of mixtures.

Download or read book Low Temperature Characterization of Foamed Warm Mix Asphalt written by Ahmad Alhasan and published by . This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, a group of technologies has been introduced in the United States that allows producing asphalt mixtures at temperatures 30 to 100oF lower than what is used in traditional hot mix asphalt (HMA). This group of technologies is commonly referred to as Warm Mix Asphalt (WMA). From among these technologies, foamed WMA produced by water injection has gained increased attention from the asphalt paving industry in Ohio since it does not require the use of costly additives. This study evaluated the low-temperature performance of foamed WMA and compared it to traditional HMA. Two asphalt binders (PG 70-22 and PG 64-28), two aggregate types (limestone and crushed gravel), and two aggregate gradations (12.5 mm NMAS and 19.0 mm NMAS) were used in this study. The low-temperature behavior of the asphalt mixtures was evaluated using the thermal stress restrained specimen test (TSRST). In addition, the low-temperature properties of the asphalt binders were measured using the bending beam rheometer (BBR). This allowed for comparing the fracture temperature obtained from the TSRST to the low-temperature performance grade obtained using the BBR test.In general, the foamed WMA mixtures exhibited warmer fracture temperatures and lower fracture stresses in the TSRST than the traditional HMA mixtures. This indicates that the HMA mixtures have better resistance to low-temperature cracking. It was found that the binder grade had the most significant effect on the fracture temperature followed by the mix type, while the aggregate type had the most significant effect on the fracture stress followed by the binder grade and the mix type. The fracture temperatures measured in the TSRST were also found to be consistent with the low-temperature performance grades obtained using the BBR test.

Download or read book Influence of Warm Mix Asphalt on Aging of Asphalt Binders written by Ala R. Abbas and published by . This book was released on 2014 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials written by Francesco Canestrari and published by Springer. This book was released on 2015-09-24 with total page 1024 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents the results of RILEM TC 237-SIB (Testing and characterization of sustainable innovative bituminous materials and systems). The papers have been selected for publication after a rigorous peer review process and will be an invaluable source to outline and clarify the main directions of present and future research and standardization for bituminous materials and pavements. The following topics are covered: - Characterization of binder-aggregate interaction - Innovative testing of bituminous binders, additives and modifiers - Durability and aging of asphalt pavements - Mixture design and compaction analysis - Environmentally sustainable materials and technologies - Advances in laboratory characterization of bituminous materials - Modeling of road materials and pavement performance prediction - Field measurement and in-situ characterization - Innovative materials for reinforcement and interlayer systems - Cracking and damage characterization of asphalt pavements - Recycling and re-use in road pavements This is the proceedings of the RILEM SIB2015 Symposium (Ancona, Italy, October 7-9, 2015).

Download or read book Influence of Aging on Foamed Warm Mix Asphalt written by Sunday Akinbowale and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the years, the use of warm mix in pavement structures has continued to gain increasing attention in United States because of its implicit advantages over the traditional hot mix. This has necessitated increased research efforts into understanding different aspects of its behaviour and performance. Aging of asphalt is particularly of much importance because it leads to several problems such as pavement rutting, fatigue cracking and thermal cracking. The aging that occurs during mixing and compaction is commonly referred to as short term aging while the aging that occurs during the pavement service life is called long term aging. The main reason for aging in binders is oxidation and binders become stiffer due to oxidation. Several research projects have been carried out on investigating the aging behavior of warm mix asphalt (WMA) produced by different chemical additives. But no major study has been conducted to understand the aging behavior of foamed WMA. Therefore, this study characterizes the aging behavior of foamed (WMA) as it compares to the traditional hot mix asphalt (HMA) using the Dynamic Shear Rheometer (DSR), Fourier Transforms Infrared Spectroscopy (FTIR), and Gel Permeation Chromatography (GPC) tests. Investigation of the effect of extraction and recovery with trichloroethylene on the stiffness of binders was initially carried out. In addition to preparation of mixtures, aging of binders (RTFO and PAV) and aging of mixtures (STOA and LTOA) being simulated in the laboratory using PG 70-22M and PG 64-22 binder grades, field cores were also obtained from test sections which had been in service for five years. Binders were extracted and recovered from both laboratory and field samples for subsequent physical and chemical tests. These results were analysed and used to evaluate the aging behavior of foamed WMA as it compares to HMA. It was observed that extraction and recovery procedure with trichloroethylene had minimal effect on PG 70-22M binders while it had a reductive effect on rutting and fatigue parameter values of PG 64-22 binders at different levels of aging. Both foamed WMA and HMA for PG 70-22M responded similarly to field and laboratory-simulated aging conditions. But for PG 64-22 binders, foamed WMA was found to be less susceptible to aging than the traditional HMA. Therefore, it implies that when the foamed warm mix technology is used, it may be expected to have a better performance in fatigue cracking but more susceptible to rutting or permanent deformation that takes place in pavement early years when compared to the traditional Hot Mix Asphalt.

Download or read book Evaluation of Warm Mix Asphalt Technologies with Respect to Binder Aging and Emissions written by Faramarz Farshidi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years Warm Mix Asphalt (WMA) technologies have been used to modify asphalt binders, with the following objectives: to decrease production and construction temperatures, reduce fumes and emissions, increase haul distance, and improve the workability of the mix. Reduced temperatures at the plant and during laydown and compaction are hypothesized to positively impact long-term oxidative aging behavior due to less oxidation/aging and result in less emissions during production and construction due to reduced production and construction temperatures. The purpose of this investigation was to quantify these improvements with respect to long-term oxidative aging in the field and environmental benefits with respect to volatile organic compounds, semi-volatile organic compounds and poly cyclic aromatic hydrocarbons in order to confirm or deny this hypothesis. This research evaluated the potential durability of WMA and Rubberized Warm Mix Asphalt (R-WMA) binders with respect to long-term aging through characterization of field-aged binders extracted and recovered from field cores. The results were compared to the control conventional Hot Mix Asphalt (HMA) and Rubberized Hot Mix Asphalt (R-HMA) samples. Binders were extracted and recovered from thirteen different test sections and a total of seven different WMA technologies were evaluated in this study. The Dynamic Shear Rheometer (DSR) was used to evaluate the rheological properties of the binders at high temperatures with respect to rutting performance in the field. The Bending Beam Rheometer (BBR) was used to characterize low temperature properties of the binder samples. A new testing procedure was developed to measure and characterize the rheological properties of the R-HMA and R-WMA binders with respect to performance-related properties in the field. The rheological results indicated that depending on the WMA technology used, the addition of WMA technologies and reduced production and compaction temperatures result in increase or decrease rutting resistance performance for WMA and R-WMA binders with respect to permanent deformation at high temperatures in the field. Both WMA and R-WMA binders studied meet the established thermal cracking criteria with respect to low temperature cracking in the field. The aging kinetics curves for WMA-treated binders are parallel to the control binders and the addition of WMA technologies including organic, chemical and mechanical foaming technologies studied in this research did not result in a different aging kinetics trend with respect to long-term aging in the field. A portable "flux" chamber was designed and fabricated to capture and directly measure emissions during paving operations. Emissions were collected in activated charcoal sorbent tubes for characterizing volatile organic compounds and semi-volatile organic compounds. XAD-2 resin tubes and filters were used to capture the gaseous phase and particulate phase of the PAH compounds, respectively. A reliable analytical method was developed to identify and quantify alkane emissions using gas chromatography mass spectrometry (GC/MS) in the laboratory. A separate method was developed for identification and characterization of trace level PAH compounds of the asphalt fumes. The results demonstrated that the warm mix asphalt technology type, plant mixing temperature and level of compaction significantly influence the emission characteristics throughout paving operations. Moreover, the emissions kinetics indicated that the majority of the reactive organic gases are volatilized in the first hour after sampling initiation (immediately after production and before compaction). To better understand and identify any chemical composition changes of the binder due to WMA technologies, nuclear magnetic resonance spectroscopy (NMR) was used for understanding structural complexities of HMA and WMA binder molecules. Qualitative analysis of both carbon and hydrogen atoms with HMA and WMA binders showed that the molecular structures of the binders are not significantly changed by the effect of WMA technologies.

Download or read book Advances in Functional Pavements written by Yuqing Zhang and published by CRC Press. This book was released on 2023-11-15 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Functional Pavements is a collection of papers presented at the 7th Chinese-European Workshop (CEW) on Functional Pavement (Birmingham, UK, 2-4 July 2023). The focus of the CEW series is on field tests, laboratory test methods and advanced analysis techniques, and covers analysis, material development and production, experimental characterization, design and construction of pavements. The main areas covered by the book include: Green pavements for circular and low-carbon economy Intelligent pavements for future and smart cities Durable pavements for long-life infrastructures Safe pavements for user-friendly build environments Advances in Functional Pavements aims at contributing to the establishment of a new generation of pavement design methodologies in which rational mechanics principles, advanced constitutive models and advanced material characterization techniques shall constitute the backbone of the design process. The book will be much of interest to professionals, academics and practitioners in pavement engineering and related disciplines as it should assist them in providing improved road pavement infrastructure to their stakeholders.

Download or read book Long and Deep Tunnels written by Vittorio Guglielmetti and published by CRC Press. This book was released on 2016-04-15 with total page 1336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design and construction of “long and deep” tunnels, i.e. tunnels under mountains, characterised by either considerable length and/or overburden, represent a considerable challenge. The scope of this book is not to instruct how to design and construct such tunnels but to share a method to identify the potential hazards related to the process of designing and constructing long and deep tunnels, to produce a relevant comprehensive analysis and listing, to quantify the probability and consequences, and to design proper mitigation measures and countermeasures. The design, developed using probabilistic methods, is verified during execution by means of the so called Plan for Advance of the Tunnel (PAT) method, which allows adapting the design and control parameters of the future stretches of the tunnel to the results of the stretches already finished, using the monitoring data base. Numerous criteria are given to identify the key parameters, necessary for the PAT procedure. Best practices of excavation management with the help of real time monitoring and control are also provided. Furthermore cost and time evaluation systems are analysed. Finally, contractual aspects related to construction by contract are investigated, for best development and application of models more appropriate for tunnelling-construction contracts. The work will be of interest to practising engineers, designers, consultants and students in mining, underground, tunnelling, transportation and construction engineering, as well as to foundation and geological engineers, urban planners/developers and architects.

Download or read book Testing and Characterization of Sustainable Innovative Bituminous Materials and Systems written by Manfred N. Partl and published by Springer. This book was released on 2018-02-01 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the detailed results of five task groups of the RILEM technical committee TC 237-SIB on Testing and Characterization of Sustainable Innovative Bituminous Materials and Systems. It concentrates on specific new topics in asphalt binder and mixture testing, dealing with new developments in asphalt testing, in particular also in view of new innovative bituminous materials, such as hot and cold recycled mixtures, grid reinforced pavements and recycled Reclaimed Asphalt Pavements (RAP), where test methods developed for traditional asphalt concrete are not a priori applicable. The main objective is providing a basis for pre-standardization by comparing different test methods and showing ways for fundamental improvements. Thus, the book also points the way for a further advanced chemo-physical understanding of materials and their role in pavement systems relying on fundamental material properties and suitable models for describing and predicting the intrinsic mechanisms that determine the material behavior.

Download or read book Aging Kinetics Characteristics of Warm Mix Asphalt Binder Using Softening Point and N pentane Asphaltene Content as the Parameters written by Jiupeng Zhang and published by . This book was released on 2015 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presented research on the aging kinetics characteristics of asphalt binder by using softening point and n-pentane asphaltene content, respectively, as parameters. Sasobit additives were added into two matrix asphalt binders to prepare the warm mix asphalt binders, and then were aged at different temperatures and time. The softening points and contents of n-pentane asphaltene were measured. Results indicated that the softening point was improved by adding the additives. Both the softening point and content of n-pentane asphaltene increased with aging temperature and aging time, and the increments of matrix asphalt binders were bigger. Taking the softening point and content of n-pentane asphaltene as the parameters, respectively, the aging kinetics models were established, and the reaction rate constants and reaction activation energies were calculated. It was found that warm mix asphalt binders had lower reaction constants and bigger reaction activation energies, that is to say the anti-aging property of warm mix asphalt was better. The anti-aging properties could be better evaluated by the aging kinetics models based on the softening point for its higher accuracy and testing convenience.

Download or read book A Comparison of Warm Asphalt Binder Aging with Laboratory Aging Procedures written by Tejash Gandhi and published by . This book was released on 2010 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Warm asphalt has been gaining increasing popularity in recent years; however there are several characteristics about warm asphalt that are still unknown. While several studies have been conducted to study the performance of warm asphalt mixtures, aging characteristics of warm mix asphalt (WMA) binders are not known in great detail. This paper presents the results of a limited study to evaluate the aging characteristics of two WMA binders artificially aged in the rolling thin film oven (RTFO) and the pressure aging vessel and comparing them with binder extracted from freshly prepared and artificially aged warm asphalt mixtures. RTFO aging was performed at 163°C and a lower temperature to simulate warm asphalt aging. Tests on binders aged in the laboratory and binders extracted from freshly mixed and aged mixtures indicated that the WMA binders extracted from WMA mixtures had significantly lower viscosities and G*/sin ? compared to binders extracted from hot mix asphalt (HMA) and binders aged in the RTFO at 163°C (325°F). This indicates that the lower mixing and compaction temperatures reduce the aging of the warm asphalt binders. Also, binders extracted from WMA had significantly lower creep stiffness values and significantly higher m-values compared to warm asphalt binders aged in the RTFO at 163°C (325°F) and binders extracted from HMA. Binders containing WMA additives did not have higher G* sin ? values, indicating that the warm asphalt additives do not negatively affect the fatigue properties of the binders. Gel permeation chromatography analysis indicated that the addition of the warm asphalt additives did not have any significant effect on the %LMS of the binders used in this study.

Download or read book Warm mix Asphalt Study written by Frank Farshidi and published by . This book was released on 2013 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characteristics of Asphalt Binders written by and published by . This book was released on 1996 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Trends in Manufacturing Technologies and Equipment written by Sergey Bratan and published by Materials Research Forum LLC. This book was released on 2022-02-25 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents the proceedings of the International Conference on Modern Trends in Manufacturing Technologies and Equipment (ICMTME 2021), held in September 2021 in Sevastopol, Russia. The conference participants came from Russia, Ukraine, Belarus, Kazakhstan, South Africa, Germany, USA, Bulgaria, Poland, China, Algeria, Mongolia, Uzbekistan, Armenia and Vietnam. The aim of the conference was to provide scientists and industrial researchers with the latest developments in manufacturing technologies, materials research, manufacturing equipment and tools, and to build up partnerships for future collaboration. Keywords: Welded Joints, Dry Building Mixtures, Tribological Properties of Sapphire, Direct Metal Deposition Modes, Production of Artificial Concrete, Wooden Structures, Rolls for Helical Rolling, Laser Treatments, Electromechanical Surfacing, Luminous Phosphate Coatings, Ventilated Brake Discs, Cutting Zone, Models for Wind Tunnels, Gas-Thermal Spraying, Water-Abrasive Cutting, Grinding Forces, CVD Coatings, Carbonate Concrete, Photocatalytic Activity of Tungsten Oxide, Maraging Steel, Corrosion of TiNi Alloy, 3D Printing, Production of Ultramarine, Injection Molding, Elastomeric Composites, Reinforcing Bars Inside Concrete Structures, Coatings for Cutting Tools, Hard Alloy Tools, Deformation of Elastic Polymer, Wearproof Composite Coatings. Rubber with Sensory Properties, Foamed Phosphate Glass for Oil Sorbents, Welded Trunk Pipelines, Biodegradable Extrusion Films, Asphalt Concrete, Mathematical Models, Electrically Conductive Materials, Belt Rotary Grinding of Aluminium Alloy Blanks.

Download or read book Mix Design Practices for Warm Mix Asphalt written by Ramon Francis Bonaquist and published by Transportation Research Board. This book was released on 2011 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: TRB's National Cooperative Highway Research Program (NCHRP) Report 691: Mix Design Practices for Warm-Mix Asphalt explores a mix design method tailored to the unique material properties of warm mix asphalt technologies. Warm mix asphalt (WMA) refers to asphalt concrete mixtures that are produced at temperatures approximately 50°F (28°C) or more cooler than typically used in the production of hot mix asphalt (HMA). The goal of WMA is to produce mixtures with similar strength, durability, and performance characteristics as HMA using substantially reduced production temperatures. There are important environmental and health benefits associated with reduced production temperatures including lower greenhouse gas emissions, lower fuel consumption, and reduced exposure of workers to asphalt fumes. Lower production temperatures can also potentially improve pavement performance by reducing binder aging, providing added time for mixture compaction, and allowing improved compaction during cold weather paving. Appendices to NCHRP Report 691 include the following. Appendices A, B, and D are included in the printed and PDF version of the report. Appendices C and E are available only online.

Download or read book Short term Laboratory Conditioning of Asphalt Mixtures written by David Newcomb and published by . This book was released on 2015 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report develops procedures and associated criteria for laboratory conditioning of asphalt mixtures to simulate short-term aging. The report presents proposed changes to the American Association of State Highway and Transportation Officials (AASHTO) R 30, Mixture Conditioning of Hot-Mix Asphalt (HMA), and a proposed AASHTO practice for conducting plant aging studies. The report will be of immediate interest to materials engineers in state highway agencies and the construction industry with responsibility for design and production of hot and warm mix asphalt.

Download or read book Testing and Characterization of Asphalt Materials and Pavement Structures written by Kun Zhang and published by Springer. This book was released on 2018-07-11 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents new studies dealing with the attempts made by the scientists and practitioners to address contemporary issues in pavement engineering such as aging and modification of asphalt binders, performance evaluation of warm mix asphalt, and mechanical-based pavement structure analysis, etc.. Asphalt binder and mixture have been widely used to construct flexible pavements. Mechanical and Chemical characterizations of asphalt materials and integration of these properties into pavement structures and distresses analysis are of great importance to design a sustainable flexible pavement. This book includes discusses and new results dealing with these issues. Papers were selected from the 5th GeoChina International Conference 2018 – Civil Infrastructures Confronting Severe Weathers and Climate Changes: From Failure to Sustainability, held on July 23 to 25, 2018 in HangZhou, China.