Bibliographies thématiques / RTFRTW

Sommaire

Articles de revues
Thèses
Chapitres de livres
Actes de conférences

Littérature scientifique sur le sujet « RTFRTW »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 10 mars 2023

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « RTFRTW ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "RTFRTW"

Li, Ning Li, Xin Po Zhao, Cai Li Zhang, Hu Hui Li et Qing Yi Xiao. « Effect of Aging on the Low Temperature Performance of Asphalt Binder ». Applied Mechanics and Materials 438-439 (octobre 2013) : 369–72. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.369.

Texte intégral

Résumé :

During the service of asphalt pavement, the aging makes asphalt binder become brittle, gradually lose flexibility and adhesion. All these result in the low-temperature properties of asphalt pavement to be poor. This paper conducts the rolling thin film oven test (RTFOT) and pressure aging vessel (PAV) test on base asphalt and rubber-modified asphalt respectively. The bending beam rheometer (BBR) test was conducted on original asphalts, rolling thin film oven test (RTFOT) residuals and RTFOT + pressure aging vessel (PAV) residuals of base asphalt and rubber-modified asphalt respectively. Results indicate that the low-temperature properties of all aged asphalts were declined. The attenuation of low-temperature properties of RTFOT + PAV residuals is larger than that of the RTFOT residuals. The attenuation of different types of asphalt is different. From the overall trend, effect of aging on the low-temperature properties of asphalt binder reduced as the test temperature reduction. The rubber-modified asphalt has superior low-temperature performance than that of base asphalt, and its low-temperature performance decreases more slowly than the base asphalt.

Styles APA, Harvard, Vancouver, ISO, etc.

Migliori, Francis, et Jean-François Corté. « Comparative Study of RTFOT and PAV Aging Simulation Laboratory Tests ». Transportation Research Record : Journal of the Transportation Research Board 1638, n^o 1 (janvier 1998) : 56–63. http://dx.doi.org/10.3141/1638-07.

Texte intégral

Résumé :

Tests were performed on unmodified asphalts of 35/50 grade penetration produced by French refineries to determine whether a prolonged pressure aging vessel (PAV) test would provide similar results to those obtained using the Strategic Highway Research Program coupled aging procedure, rolling thin film oven test (RTFOT) and PAV. Asphalts subjected only to PAV tests and identical samples after RTFOT and increasing PAV time were compared on the basis of ( a) conventional consistency tests, penetration at 25°C, ring and ball softening temperature; ( b) asphaltene content; ( c) creep rheological tests at low temperature with the bending beam rheometer; and ( d) complex modulus tests with the Metravib dynamic rheometer. The results show that a hypothesis of equivalence between the effects of ( a) RTFOT and 5 h of PAV aging at 100°C and under 2.1 MPa and ( b) RTFOT + 20 h of PAV and 25 h of PAV under the same conditions seems acceptable for the category of asphalts investigated.

Styles APA, Harvard, Vancouver, ISO, etc.

Rajput, R. P. S., S. S. Goliya et R. Mehar. « A study on the effect of aging on pmb40 and crmb55 in bituminous concrete layers ». IOP Conference Series : Earth and Environmental Science 1130, n^o 1 (1 janvier 2023) : 012035. http://dx.doi.org/10.1088/1755-1315/1130/1/012035.

Texte intégral

Résumé :

Abstract Aging occurs in bituminous materials throughout the construction and service lifespan of asphalt pavement, and it has a substantial impact on their performance. Bitumen aging is one of the primary causes of asphalt pavement degradation. As bitumen ages, asphalt surfaces lose their capacity to alleviate tension during the cooling process, increasing the danger of cracking. The thin film oven test (TFOT) and the rolling thin film oven test (RTFOT) are two extensively used short-term aging tests (RTFOT). The rotating cylinder-aging test (RCAT) and pressure aging vessel are two extensively used tests in the long-term aging of bitumen (PAV). The suggested research includes the comparison of un-modified bitumen and modified bitumen of waste crumb rubber and plastic rubber. This research was conducted on the aging of different grades of bitumen, that are two modified bitumen, which are PMB40 & CRMB55. After the aging of the bitumen, we conducted some physical property tests on the normal bitumen and RTFOT-modified bitumen. The outcome of the testing of the physical properties was that the RTFOT modified bitumen gained more strength as compared to the normal bitumen after the testing of physical properties of bitumen (Normal Bitumen & RTFOT Modified Bitumen) prepared samples for testing the Marshall Properties. After testing, Marshall Properties’ research can conclude that the RTFOT Modified Bitumen provides more strength compared to the normal bitumen. The RTOFT modified bitumen can be used in rural areas to provide a better pavement surface and longevity of the pavement. Through the aging of bitumen, the adhesion property between bitumen and aggregate becomes strong, so that in a high traffic area, cracks do not develop easily

Styles APA, Harvard, Vancouver, ISO, etc.

Shalaby, Ahmed. « Modelling short-term aging of asphalt binders using the rolling thin film oven test ». Canadian Journal of Civil Engineering 29, n^o 1 (1 février 2002) : 135–44. http://dx.doi.org/10.1139/l01-086.

Texte intégral

Résumé :

Simulation of short-term aging of asphalt binders is a widely used procedure in asphalt binder characterization for predicting the binder response to plant mixing and paving under controlled laboratory conditions. There are two laboratory test methods for evaluating the short-term aging of asphalt binders: (i) a method using rotating pans filled with a thin asphalt film termed thin film oven test (TFOT) and (ii) a method using rolling cylindrical asphalt containers termed rolling thin film oven test (RTFOT). In this paper, an attempt is made to develop generalized models for short-term aging effects using the RTFOT aging time as a benchmark. Six binder types representing two PG grades and three source suppliers are conditioned to varying levels of RTFOT aging and tested using the dynamic shear rheometer (DSR). Aging effects are modelled using independent temperature shift models for the shear modulus and phase angle. The paper discusses the sources of errors in producing generalized models and some potential applications of aging models. The research revealed that it is possible to develop and implement such models for unmodified binders.Key words: asphalt, aging, RTFOT, DSR, binder rheology, shear modulus, phase angle.

Styles APA, Harvard, Vancouver, ISO, etc.

Hou, Yue Qin, Xiao Ping Ji et Xue Zhang Tan. « Application of Nonlinear Differential Dynamic Model to Evaluate Long-Term Aging Behavior of SBS Modified Asphalt ». Advanced Materials Research 710 (juin 2013) : 376–81. http://dx.doi.org/10.4028/www.scientific.net/amr.710.376.

Texte intégral

Résumé :

In order to study the long-term aging behavior of SBS modified asphalt, a nonlinear differential dynamic model was developed and the aging tests with rolling thin film oven test (RTFOT) for SBS modified asphalt were carried out. The dynamic model was developed referring to the population developing model with two parameters, namely average aging rate and aging ratio. And the differentiation of the dynamic model was the aging rate equation with which can calculate the aging rate at any time. The aging tests with RTFOT for SBS modified asphalt at different times were carried out and the penetration, ductility at 5°C, softening point and viscosity at 135°C were measured after RTFOT. With the rest results, the two parameters of nonlinear differential dynamic model of above four indexes were determined, and further the aging rate equations were deduced. The research results show that the nonlinear differential dynamic model can exactly describe the varying behavior of penetration, ductility, softening point and viscosity of SBS modified asphalt after RTFOT aging test with different time. The aging rate reach maximum value at the beginning and becomes smaller and smaller as the time goes.

Styles APA, Harvard, Vancouver, ISO, etc.

Li, Bo, Yu Wang, Xiaoyu Ren, Xuqiu Teng et Xiuli Su. « Influence of Ultraviolet Aging on Adhesion Performance of Warm Mix Asphalt Based on the Surface Free Energy Theory ». Applied Sciences 9, n^o 10 (17 mai 2019) : 2046. http://dx.doi.org/10.3390/app9102046.

Texte intégral

Résumé :

To explore the effect of ultraviolet (UV) aging on the adhesion properties of warm mix asphalt (WMA), WMA binders were prepared by adding Evotherm M1 and Sasobit into base asphalt. The base asphalt and two WMA binders were aged using a self-made UV aging box after a rolling thin-film oven test (RTFOT). As a comparison, pressure aging vessel (PAV) tests were performed for asphalt binders after RTFOT. The contact angles between the WMA binder and distilled water, glycerol, and formamide, before and after UV aging, were measured using the sessile drop method. On the basis of the surface free energy (SFE) theory, the SFE and its components, cohesion work, adhesion work, peeling work, and compatibility rate, before and after the UV aging of WMA, were obtained. The results show that the contact angle between WMA and water gradually increases with the degree of UV aging, which indicates that the aging increases the hydrophobicity of asphalt. After the RTFOT aging, UV aging at different times, and PAV aging, the SFE and its component, as well as cohesion work for all asphalt binders were reduced. The attenuation was severe after UV aging, followed by PAV aging and RTFOT aging. With the extension of UV aging time, the adhesion work, hot mix asphalt, and limestone aggregate compatibility rate gradually reduced, the peeling work increased, and the overall adhesion performance became poor. Under the aging effect of RTFOT and PAV, the Evotherm M1 WMA had the strongest anti-peeling ability, better compatibility, and the best adhesion. When the UV aging time of Sasobit WMA reached 100 h, the adhesion performance increased.

Styles APA, Harvard, Vancouver, ISO, etc.

Rojas, Joyce, Heriberto Amado, Wilmar Fernández et Freddy Reyes. « Efectos de la radiación ultravioleta en asfaltos colombianos ». Revista científica 1, n^o 15 (5 mars 2013) : 96. http://dx.doi.org/10.14483/23448350.3947.

Texte intégral

Résumé :

Esta investigación tuvo como objetivo el envejecimiento a corto y largo plazo de dos asfaltos colombianos (60/70 y 80/100 de Barrancabermeja) a través de ensayos como Horno Rotatorio de Película Delgada (RTFO, por sus siglas en inglés) y Envejecimiento Acelerado de Vasija a Presión (PAV, por sus siglas en inglés), y un ensayo adicional de RTFOT más radiación Ultra Violeta UV a dos periodos distintos de exposición. Las propiedades reológicas y físicas de estos ligantes fueron analizadas en todas sus etapas mediante ensayos de penetración, ductilidad, punto de ablandamiento, viscosímetro rotacional y Reómetro de Corte Dinámico (DSR, por sus siglas en inglés). Los resultados muestran que tanto para la caracterización física, como para la caracterización reológica, el comportamiento de las muestras de los ligantes tratados con RTFOT y PAV es similar a las muestras tratadas con RTFOT y radiación UV por un periodo de 100 horas.

Styles APA, Harvard, Vancouver, ISO, etc.

QasemJaber, Zahraa, et Mohammed Issam Younis. « Design and Implementation of Real Time Face Recognition System (RTFRS) ». International Journal of Computer Applications 94, n^o 12 (16 mai 2014) : 15–22. http://dx.doi.org/10.5120/16395-6014.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Gunka, Volodymyr, Yurii Hrynchuk, Iurii Sidun, Yuriy Demchuk, Yuriy Prysiazhnyi et Michael Bratychak. « Production of Bitumen Modified with Low-Molecular Organic Compounds from Petroleum Residues. 6. Temperature Effect on the Chemical Modification of Bitumen with Maleic Anhydride ». Chemistry & ; Chemical Technology 16, n^o 3 (30 septembre 2022) : 475–83. http://dx.doi.org/10.23939/chcht16.03.475.

Texte intégral

Résumé :

The oxidized bitumen produced at the Ukrainian refinery was modified with maleic anhydride. The process temperature was proved to have the most significant effect on modification. The chemical interaction of maleic anhydride with the components of oxidized bitumen was confirmed. At low temperatures (up to 403 K) the chemistry of the modification process is another than chemistry of the process carried out at high temperatures. The structures of the modified bitumen were established at different process temperatures (403, 423 and 443 K) using FTIR spectroscopy. A thin film heating at 436 K (RTFOT method) was performed for the bitumen under study. It was found that for bitumen modified at 403 K, the formed structure is destroyed after heating by RTFOT, which is confirmed by a decrease in the softening point of the bitumen. The FTIR spectra of the original oxidized bitumen and bitumen modified with maleic anhydride at 403 and 443 K were recorded after the RTFOT heating process. Based on the obtained data, the structural transformations that occurred during heating were established.

Styles APA, Harvard, Vancouver, ISO, etc.

Wang, Sheng, Weidong Huang, Xueyan Liu et Peng Lin. « Aging Characteristics of Rubber Modified Bitumen Mixed with Sulfur after Terminal Blend Process ». Sustainability 14, n^o 5 (24 février 2022) : 2612. http://dx.doi.org/10.3390/su14052612.

Texte intégral

Résumé :

The influence of sulfur on the chemical, rheological, and aging resistance of terminal blend rubberized bitumen (TBRB) was studied. TB hybrid bitumen (TBHB) was prepared from with different sulfur contents (0.1, 0.2, 0.3, 0.4 wt%) and TBRB prepared with neat bitumen and crumb rubbers at 20% content. TBHB binders were aged by rolling thin film oven test (RTFOT) and pressure aging vessel (PAV), respectively. The chemical composition of TBHB binders was monitored by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). Rheological properties of all TBHB samples were tested. Chemical composition results show that TBHB can inhibit the degradation of polybutadiene compared with TBRB in the RTFOT stage, and the polybutadiene degradation is the main process of TBHB in the RTFOT stage, while the TBHB is mainly desulfurized after PAV aging. Meanwhile, the increase in sulfur content in the TBHB can improve the desulfurization degree of the TBHB binder after PAV. TBRB containing sulfur can improve the mechanical properties and elasticity and reduce the hardening degree during aging. Moreover, blending sulfur into the TBRB caused a lower complex modulus aging index after aging, which indicates that TBHB has superior aging resistance.

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Thèses sur le sujet "RTFRTW"

COROLLI, LUCA. « Deterministic and Stochastic Optimization For Heterogeneous Decision Phases In The Air Traffic Domain ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/50551.

Texte intégral

Résumé :

Scheduling is a complex activity that is needed in a large number of fields, which can involve heterogeneous factors and that may have different goals. In this thesis, scheduling problems that involve the air traffic field at different phases are faced. At each phase, the different characteristics of the problems are considered, devoting special attention to uncertainty. Given the heterogeneous characteristics and goals of the problems, different models and methods are proposed to solve each of them. The first analyzed phase is the strategic phase. It takes place around six months before the operation of flights, when they need to be assigned scheduled departure and arrival times at the airports where they operate. Future capacity realizations are very difficult to forecast at this phase, as capacity is influenced by weather conditions. A two-stage stochastic programming model with two alternative formulations is proposed to capture this uncertainty. Since the number of scenarios may be extreme, Sample Average Approximation is used to solve the model. The utilization of the proposed model allows to identify advantageous tradeoffs between schedule/request discrepancies, i.e., the distance between the allocated schedule and airline requests, and operational delays. This tradeoff can result in substantial reductions of the cost of delays for airlines. In the computational experiments, delays were reduced up to 45% on an instance representing a network of European airports. The second considered phase is the tactical phase, which takes place on the day of operation of flights. At this time, complete flight plans need to be defined, specifying the route and operation times of flights. This is done considering two different sources of uncertainty. First, uncertainty on capacity availability is taken into account, similarly to the strategic phase. However, the number of capacity realization scenarios is now small, as they can be defined using available weather forecasts. The problem of minimizing delay costs considering this source of uncertainty is the Stochastic Air Traffic Flow Management problem. A two-stage stochastic programming model with two alternative formulations is proposed to solve this problem. An ad-hoc heuristic that takes advantage of the good structure of the model is used to solve problem instances within short computation times. The analysis of the Value of the Stochastic Solution shows that the proposed stochastic model can significantly reduce delay costs when bad weather affects the whole network. Second, the implicit uncertainty on the departure time of flights is taken into account. This kind of uncertainty involves operations that may cause a delay on the scheduled departure time of a flight. The flexibility of the scheduled time of departure, as well as the other flight operations, is determined defining time windows within which flights are granted capacity resources to operate. The narrower a time window, the more critical a flight operation. The problem of minimizing delay cost and maximizing time windows is faced by the Air Traffic Flow Management Problem with Time Windows. The problem is formulated with two alternative deterministic models, one of which is able to provide time windows in 40" on average for instances involving over 6,000 flights. Less conservative criteria to reserve capacity within time windows can also be used. Despite not granting the possibility for a flight to execute its operations at every instant of a time window, the implementation of these alternative criteria is shown to be viable. In fact, less than 0.14% of flights were subject to capacity shortages in the analyzed cases. Finally, the operational phase takes place when operations are being executed. The goal at this phase is to manage the final departure times announced by flights - with uncertain information becoming deterministic - allowing them to depart at the announced time even if this time exceeds the assigned departure time window. This problem is named Real Time Flight Rescheduling with Time Windows. Resources are provided to flights that need them by reallocating previously reserved capacity with an algorithm that follows the Ration-By-Schedule mechanism. Both the practical usage of time windows and the impact of collaboration among airlines are studied. While airline collaboration limits time window flexibility up to some time before the scheduled departure of a flight, it can allow to reduce additional flight delays by over 14%. This thesis is a first work that involves determining flight schedules from the moment of their definition to the time of execution of flights. Providing cost reductions by considering the different factors that influence each decision phase can lead to a global improvement of the management of flight operations, whose delays are very expensive in practice for airlines.

Styles APA, Harvard, Vancouver, ISO, etc.

Cavalcante, Priscilla Noronha. « Propriedades mecÃnicas de cimento asfÃltico RTFOT e adicionados de PPA e LCC por microscopia de forÃa atÃmica ». Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8926.

Texte intégral

Résumé :

O estudo reolÃgico do Cimento AsfÃltico de PetrÃleo (CAP) Ã de fundamental importÃncia para a determinaÃÃo de sua performance na fabricaÃÃo de estradas. Usualmente os parÃmetros reolÃgicos deste material sÃo obtidos por meio de ensaios dinÃmicos atravÃs de um reÃmetro de cisalhamento. O presente trabalho tem por objetivo estudar as propriedades microreolÃgicas do CAP atravÃs da tÃcnica de espectroscopia de forÃa utilizando um microscÃpio de forÃa atÃmica. A Microscopia de ForÃa AtÃmica mostra ser uma ferramenta Ãtil na investigaÃÃo de propriedades mecÃnicas de sistemas microscÃpicos. O principio bÃsico de atuaÃÃo do AFM Ã medir as forÃas micromecÃnicas entre a sonda do equipamento e a amostra analisada podendo-se obter nÃo apenas o mapa topogrÃfico da superfÃcie em anÃlise, mas tambÃm informaÃÃes a respeito das propriedades reolÃgicas do material tais como elasticidade, viscosidade, adesÃo do material, entre outras, assim como observar regiÃes onde essas propriedades diferem numa mesma amostra. Amostras de CAP puro 50/70, CAP envelhecido e aditivado com 2% de LCC e 1% de PPA foram analisadas. A partir dos dados das curvas de forÃa, com base em uma ferramenta computacional desenvolvida para esse tipo de anÃlise, foram obtidos o mÃdulo de Young, a viscosidade, a adesÃo, work difference e slope. Para cada tipo de amostra foram confeccionados 3 lamÃnulas, as quais seriam usadas para fazer as medidas no AFM, e cada lamÃnula, analisadas em 3 regiÃes diferentes de 50 Âm X 50 Âm. As identaÃÃes foram realizadas em 4 frequÃncias diferentes: 0,5 hz, 1 hz, 5 hz e 28 hz. AlÃm dessas medidas, foram obtidos imagens de fase, imagens topogrÃficas e imagens de friction para cada tipo de amostra.

Styles APA, Harvard, Vancouver, ISO, etc.

Cavalcante, Priscilla Noronha. « Propriedades mecânicas de cimento asfáltico RTFOT e adicionados de PPA e LCC por microscopia de força atômica ». reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/9776.

Texte intégral

Résumé :

CAVALCANTE, Priscilla Noronha. Propriedades mecânicas de cimento asfáltico RTFOT e adicionados de PPA e LCC por microscopia de força atômica. 2012. 120 f. Dissertação (Mestrado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2012.
Submitted by Edvander Pires (edvanderpires@gmail.com) on 2014-11-13T20:13:56Z No. of bitstreams: 1 2012_dis_pncavalcante.pdf: 11687002 bytes, checksum: b3ef71cffeecc3775c5d706c1eaab862 (MD5)
Approved for entry into archive by Edvander Pires(edvanderpires@gmail.com) on 2014-11-13T20:37:03Z (GMT) No. of bitstreams: 1 2012_dis_pncavalcante.pdf: 11687002 bytes, checksum: b3ef71cffeecc3775c5d706c1eaab862 (MD5)
Made available in DSpace on 2014-11-13T20:37:03Z (GMT). No. of bitstreams: 1 2012_dis_pncavalcante.pdf: 11687002 bytes, checksum: b3ef71cffeecc3775c5d706c1eaab862 (MD5) Previous issue date: 2012
O estudo reológico do Cimento Asfáltico de Petróleo (CAP) é de fundamental importância para a determinação de sua performance na fabricação de estradas. Usualmente os parâmetros reológicos deste material são obtidos por meio de ensaios dinâmicos através de um reômetro de cisalhamento. O presente trabalho tem por objetivo estudar as propriedades microreológicas do CAP através da técnica de espectroscopia de força utilizando um microscópio de força atômica. A Microscopia de Força Atômica mostra ser uma ferramenta útil na investigação de propriedades mecânicas de sistemas microscópicos. O principio básico de atuação do AFM é medir as forças micromecânicas entre a sonda do equipamento e a amostra analisada podendo-se obter não apenas o mapa topográfico da superfície em análise, mas também informações a respeito das propriedades reológicas do material tais como elasticidade, viscosidade, adesão do material, entre outras, assim como observar regiões onde essas propriedades diferem numa mesma amostra. Amostras de CAP puro 50/70, CAP envelhecido e aditivado com 2% de LCC e 1% de PPA foram analisadas. A partir dos dados das curvas de força, com base em uma ferramenta computacional desenvolvida para esse tipo de análise, foram obtidos o módulo de Young, a viscosidade, a adesão, work difference e slope. Para cada tipo de amostra foram confeccionados 3 lamínulas, as quais seriam usadas para fazer as medidas no AFM, e cada lamínula, analisadas em 3 regiões diferentes de 50 µm X 50 µm. As identações foram realizadas em 4 frequências diferentes: 0,5 hz, 1 hz, 5 hz e 28 hz. Além dessas medidas, foram obtidos imagens de fase, imagens topográficas e imagens de friction para cada tipo de amostra.

Styles APA, Harvard, Vancouver, ISO, etc.

Lindström, Björn. « Analys av Nedbrytningsprodukter av Polymerer för Bitumenändamål ». Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9832.

Texte intégral

Résumé :

This project was aimed to study the degradation of polystyrene-butadiene-styrene block copolymer (SBS). SBS is used to modify bitumen, the binder in asphalt. From earlier studies it is known that SBS degrades in bitumen, but the degradation products have not been identified. To be able to determine the long term effects of SBS in the environment, degradation products need to be identified. Polystyrene forms rigid blocks with polybutadiene as a rubbery matrix between the ridgid blocks. When blended in bitumen, the polystyrene blocks are crosslinked to form a three dimensional network. SBS is an elastomer and has the ability to regain its shape after being a subject of mechanical force. According to the pre references the polymers had to be degraded in similar ways as they would in bitumen. Since bitumen is a very complex matrix with high boiling point and viscosity, there would be difficulties separating polymers from the bitumen. We made an assumption that it would be plausible for the degradation products formed in bitumen to form even with no bitumen present. Four different SBS polymers were used. One of the polymers was branched. Another had a high content of 1-2 polybutadiene. The third was a diblock copolymer (SB) with low styrene content compared to the others. The last was a linear SBS. The polymers were degraded in pieces of apparatus used for study ageing characteristics of bitumen as well as they were aged by refluxing in hexane. The degradation products were extracted by Solid Phase Extraction (SPE) and identified by GC-MS. Due to instrumental limits there were not many degradation products identified. The main products detected included saturated hydrocarbons in the range of 16-31 carbon atoms as well as squalene.

I det här projektet studerades nedbrytning av styren-butadien-styren block kopolymerer (SBS). SBS används för att modifiera bitumen vars användningsområde är som bindemedel i asfalt. Tidigare studier har visat att SBS bryts ned i bitumen, men nedbrytningsprodukterna har inte identfierats. För att kunna avgöra vad SBS har för långsiktiga effekter på miljön måste nedbrytnignsprodukterna identifieras. I SBS bildar polystyren styva block medan polybutadien fungerar som flexibla bryggor mellan polystyrenblocken. När SBS blandas med bitumen korslänkas polystyrenblocken så att ett tredimensionellt nätverk bildas. Eftersom SBS är en elastomer har den förmågan att återfå sin ursprungliga form efter att ha blivit utsatt för mekanisk stress. Enligt de givna förutsättningarna för studien skulle polymererna brytas ned på samma sätt som om de skulle ha varit lösta i bitumen. Eftersom bitumen är en komplex matris med hög kokpunkt och viskositet skulle det varit svårt att separera polymererna och deras nedbrytningsprodukter från bitumenet. Vi gjorde ett antagande om att det förmodligen bildas samma nedbrytningsprodukter som om bitumen varit närvarande även om nedbrytningen sker utan bitumen närvarande. Fyra olika SBS polymerer användes. En av polymererna var grenad. En annan hade en stor andel 1,2-polybutadien. Den tredje var en diblock kopolymer (SB) med lågt styren innehåll jämfört med de andra. Den sista polymeren var linjär. Polymererna åldrades i apparatur framtagen för att studera åldring av bitumen. Polymererna åldrades även genom att återloppskokas i hexan. Nedbrytningsprodukterna extraherades via fastfasextraktion (SPE) och identifierades med GC-MS. Genom instrumentella begränsningar kunde bara ett fåtal nedbrytningsprodukter identifieras. Bland de produkter som identifierades fanns alkaner och alkener med mellan 16 och 31 kolatomer, men även skvalen identifierades som nedbrytningsprodukt. Lågmolekylära ämnen kan ha ventilerats bort för att vi inte hade tillgång till apparatur för adsorbtion av flyktiga ämnen för injektion i GC-MS.

Styles APA, Harvard, Vancouver, ISO, etc.

Lamperti, Riccardo. « Rheological and energetic characterization of wax-modified asphalt binders ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4260/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Mazzotta, Francesco. « Studio reologico avanzato di bitumi modificati ed additivati:proposta di una nuova procedura di aging ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4257/.

Texte intégral

Résumé :

Le problematiche ambientali e socio – economiche legate alla costruzione di nuove infrastrutture viarie, impongono la progettazione e costruzione di strade che combinino ad elevati standard prestazionali, la riduzione dell’impatto ambientale in fase realizzativa e manutentiva. Quanto detto avvalora il crescente utilizzo di materiali bituminosi modificati con polimeri ed additivati con cere. I primi conferiscono alla miscela maggiore elastoplasticità, incrementandone la durabilità e la resistenza a fatica. Nei secondi la presenza del materiale paraffinico contribuisce a ridurre la viscosità del bitume, il che consente il notevole abbassamento della temperatura di produzione e stesa della miscela. Numerosi studi inoltre hanno dimostrato che le caratteristiche meccaniche della pavimentazione sono fortemente influenzate dal grado di ossidazione delle componenti organiche del bitume, ovvero dal fenomeno dell’invecchiamento o aging. Risulta pertanto fondamentale affiancare allo studio reologico del bitume, prove di simulazione dell’ invecchiamento nel breve e lungo termine. Nel corso della seguente ricerca si provvederà pertanto ad analizzare leganti modificati ed additivati secondo la teoria della viscoelasticità, simulando le reali condizioni di carico ed invecchiamento alle quali il bitume è sottoposto. Tutte le prove di caratterizzazione reologica avanzata prevederanno l’utilizzo del DSR (Dynamic Shear Rheometer) in varie configurazioni di prova e si simulerà l’invecchiamento a breve termine mediante RTFOT (Rolling thin film oven test). Si proporrà inoltre una nuova procedura di aging invecchiando il bitume alla temperatura di equiviscosità o Twork , ovvero a quel valore della temperatura tale per cui, in fase di messa in opera, si avrà una distribuzione molecolare omogenea del modificante all’interno del bitume. Verranno quindi effettuate ulteriori prove reologiche sui leganti invecchiati a tale temperatura. Si darà infine supporto ai risultati della ricerca effettuando prove chimiche con la tecnica analitica FTIR (Fourier Transform Infrared Spectroscopy), analizzando i cambiamenti molecolari avvenuti nel bitume a seguito dell’aggiunta del modificante e dell’invecchiamento.

Styles APA, Harvard, Vancouver, ISO, etc.

Rous, Vojtěch. « Odolnost asfaltových pojiv proti stárnutí ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226448.

Texte intégral

Résumé :

Asphalt binder ageing and experiences with various ageing methods from abroad are described in this thesis. The practical part deals with the RTFOT aging and with the influence of the duration of this test. The comparison of test results is conducted before and after the aging by values of needle penetration, elastic recovery, softening point and resilience tests are evaluated and compared.

Styles APA, Harvard, Vancouver, ISO, etc.

Bernardoni, Fausto. « Caratterizzazione delle proprietà reologiche dei bitumi tiepidi fluidificati ed identificazione di una procedura ottimale di invecchiamento ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2857/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Ali, Mahdi. « Study of the bitumen aging effects on the rheological properties and fatigue behavior ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16255/.

Texte intégral

Résumé :

A study of bitumen aging effects on the rheological properties and fatigue behavior is carried out on five polymer modified bitumen provided by an oil company. Dynamic Shear Rheometer (DSR), is used to perform advanced experimental investigation. It allows practicing frequency sweep tests, fatigue tests and time sweep tests. Polymer modified bitumen with different percentage of SBS with or without the presence of crumb rubber are tested before and after short and long aging processes. Master curves were generated based on frequency sweep tests data, they are studied, and a comparison was conducted between each bitumen before and after aging. In this thesis, the DSR is presented, as well as the testing procedure and the tested materials. A fatigue life analysis of the results, based on the use of two different criteria, the first criterion is classically used: it consists in defining the failure as a 50% loss of the initial stiffness. The other criteria based on dissipated energy data. This thesis provides results which show the effects of several factors on fatigue and healing response such as bitumen type, ageing, the presence of rubber and polymer modification.

Styles APA, Harvard, Vancouver, ISO, etc.

Hotař, Petr. « Reologické vlastnosti asfaltových pojiv ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226951.

Texte intégral

Résumé :

The comparison of rheological properties (complex shear modulus and phase angle and dynamic viscosity) of four paving bitumens and two polymer modified bitumens is performed in this diploma thesis. Furthermore, the empirical tests (needle penetration and softening point) were determined on these binders. Effect of asphalt binders aging was modeled using RTFOT test and modified RTFOT test (3 x RTFOT).

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Chapitres de livres sur le sujet "RTFRTW"

Marquês, Catarina, Ana Margarida Ferreira et Fernando Oliveira. « Modular Design and Technology for Diversity and a More Sustainable Fashion. The RTFKT X Nike and CLO Case Studies ». Dans Springer Series in Design and Innovation, 94–103. Cham : Springer Nature Switzerland, 2022. http://dx.doi.org/10.1007/978-3-031-20364-0_9.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

« tilt rtft of bllt ». Dans Katherine Philips (1631/2–1664) : Printed Letters 1697–1729, 86–91. Routledge, 2017. http://dx.doi.org/10.4324/9781315251165-17.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "RTFRTW"

Haji, Suad, et Asaf Varol. « Real time face recognition system (RTFRS) ». Dans 2016 4th International Symposium on Digital Forensic and Security (ISDFS). IEEE, 2016. http://dx.doi.org/10.1109/isdfs.2016.7473527.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Ping, Li, Xu Feng et Zhang Zhengqi. « Research on the Aplicatility of RTFOT Used with Modified Asphalt ». Dans 2009 Second International Conference on Intelligent Computation Technology and Automation. IEEE, 2009. http://dx.doi.org/10.1109/icicta.2009.637.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Lu, Shengye, et Hao Jiang. « RTFW : An Access Control Model for Workflow Environment ». Dans 2006 10th International Conference on Computer Supported Cooperative Work in Design. IEEE, 2006. http://dx.doi.org/10.1109/cscwd.2006.253207.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Abegunde, Jacob, Hannan Xiao et Joseph Spring. « Resilient Tit-For-Tat (RTFT) A game solution for wireless misbehaviour ». Dans 2015 International Wireless Communications and Mobile Computing Conference (IWCMC). IEEE, 2015. http://dx.doi.org/10.1109/iwcmc.2015.7289203.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!