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Asfaltové směsi s použitím vyššího množství R-materiálu / Asphalt mixtures with the use of higher amount of RAPMucha, Bohumír January 2014 (has links)
At the beginning of the Master’s thesis the asphalt mixture of the type asphalt concrete and its basic properties are described. The main point of this work is to compare the functional properties of asphalt mixtures with the addition of higher amount of RAP and various rejuvenators used in the experimental section. From individual samples of asphalt mixtures taken during the laying, the control tests were carried out and the process of permanent deformation with the wheel tracking test was monitored. After that, using functional tests the properties of asphalt mixtures with conventional modified and unmodified asphalt bitumen enriched with the addition of declaring similar properties were compared.
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Fundamental investigation to improve the quality of cold mix asphaltKhan, Abdullah January 2016 (has links)
Cold mix asphalt (CMA) emulsion technology could become an attractive option for the road industry as it offers lower startup and equipment installation costs, energy consumption and environmental impact than traditional alternatives. The adhesion between bitumen and aggregates is influenced by diverse parameters, such as changes in surface free energies of the binder and aggregates or the presence of moisture or dust on the surface of aggregates, mixing temperatures, surface textures (including open porosity), nature of the minerals present and their surface chemical composition, as well as additives in the binder phase. The performance of cold asphalt mixtures is strongly influenced by the wetting of bitumen on surfaces of the aggregates, which is governed by breaking and coalescence processes in bitumen emulsions. Better understanding of these processes is required. Thus, in the work this thesis is based upon, the surface free energies of both minerals/aggregates and binders were characterized using two approaches, based on contact angles and vapor sorption methods. The precise specific surface areas of four kinds of aggregates and seven minerals were determined using an approach based on BET (Brunauer, Emmett and Teller) theory, by measuring the physical adsorption of selected gas vapors on their surfaces and calculating the amount of adsorbed vapors corresponding to monolayer occupancy on the surfaces. Interfacial bond strengths between bitumen and aggregates were calculated based on measured surface free energy components of minerals/aggregates and binders, in both dry and wet conditions. In addition, a new experimental method has been developed to study bitumen coalescence by monitoring the shape relaxation of bitumen droplets in an emulsion environment. Using this method, the coalescence of spherical droplets of different bitumen grades has been correlated with neck growth, densification and changes in surface area during the coalescence process. The test protocol was designed to study the coalescence process in varied environmental conditions provided by a climate-controlled chamber. Presented results show that temperature and other variables influence kinetics of the relaxation process. They also show that the developed test procedure is repeatable and suitable for studying larger-scale coalescence processes. However, possible differences in measured parametric relationships between the bitumen emulsion scale and larger scales require further investigation. There are several different research directions that can be explored for the continuation of the research presented in this thesis. For instance, the rationale of the developed method for analyzing coalescence processes in bitumen emulsions rests on the assumption that the results are applicable to large-scale processes, which requires validation. A linear relationship between the scales is not essential, but it is important to be able to determine the scaling function. Even more importantly, qualitative effects of the investigated parameters require further confirmation. To overcome the laboratory limitations and assist in the determination of appropriate scaling functions further research could focus on the development of a three-dimensional multiphase model to study coalescence processes in more detail, including effects of surfactants, pH and other additives such as mineral fillers and salts. Additionally, better understanding of the breaking process and water-push out could help significantly to optimize CMA mix design. Different methods, both numerical and experimental could be explored for this. / Cold mix asphalt (CMA) eller kall asfaltbetong med hjälp av emulsionsteknik kan vara ett attraktivt alternativ för vägbyggnadsindustrin då det möjliggör lägre uppstart- och investeringskostnader, lägre energiförbrukning och mindre miljöpåverkan än traditionella alternativ. Adhesionen mellan bindemedel och stenpartiklarna påverkas av ett flertal parametrar, så som förändring i fri ytenergi hos både bindemedel och partiklar i närvaro av fukt eller damm på stenytorna, blandningstemperatur, yttextur (inklusive ytporositet), mineralegenskaper och ytornas kemiska sammansättning lika väl som tillsatsmedel i bindemedlen. Beteendet hos kall asfaltbetong är starkt påverkad av vätningsegenskaperna hos bindemedlet när det kommer i kontakt med stenmaterialet och detta i sin tur är beroende på bitumenemulsionens brytegenskaper och förmåga att blandas. Bättre förståelse av dessa processer är av största vikt. I detta arbete är avhandlingen baserad på fri ytenergi hos både mineraler/aggregat och bindemedel, baserat på kontaktvinkel och på ångabsorptionsmetoder. Den exakta specifika ytan hos fyra typer av aggregat och sju mineraler undersöktes med en metod baserad på BET (Brunauer, Emmett och Teller):s teorier genom att mäta den fysiska adsorptionen av utvalda gaser på ytorna och beräkna mängden adsorberad ånga som korresponderade mot ytlagret. Styrkan hos kontaktytornas bindning mellan bindemedlet och stenaggregaten beräknades baserat på mätningar av den fria ytenergin hos bägge ingående komponenterna, dels i torrhet dels i våta omgivningar. Som tillägg har en ny experimentell metod utvecklats för att studera bitumens blandbarhet genom att studera bitumendroppars relaxation i en emulsionsmiljö. Genom att använda denna metod har korelationen mellan sväriska droppar av bitumen undersökts mot förändringen i ytans area under blandningsprocessen. Testprotokollet utformades för att studera blandningsprocessen i varierande miljöer i en klimatkammare. Presenterade resultat visar att temperatur och andra variabler påverkar de kinetiska förhållandena vid relaxationsprocessen. De visar även att den utvecklade testmetoden är repeterbar och passar för studier av storskaliga blandningsprocesser. Det bör dock påpekas att vidare studier krävs för att påvisa skillnaderna mellan bitumenemulsionsskalan och större skalor. Framtida forskning kommer att koncentreras på utveckling av tredimensionella multifasmodeller för att studera blandningsförlopp på en mer detaljerad nivå, inkluderande effekter på ytaktiva ämnen, pH-värden och andra additativ så som mineralfiller och salt. Som tillägg kommer nyttan av nya karaktäriseringsmetoder att utvärderas, så som lågvikelspridning av neutroner eller kombinationer av röntgen, neutronradiologi och datortomografi, för att studera brytmekanismer hos bitumenemulsioner vid kontakt med mineraler och aggregat. / <p>QC 20160901</p>
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Využití R-materiálu v asfaltových směsích s pojivem typu PMB / Use of R-material in asphalt mixtures with PMB type binderNavrátilová, Pavlína Unknown Date (has links)
The diploma thesis is focused on the use of R-material in asphalt mixtures with a PMB type binder. The work is divided into a theoretical part and a practical part. The theoretical part describes the acquisition of R-material by road milling, the use of R-material, the binder used in the practical part of the work and the types of recycling. The practical part deals with the design of four types of asphalt mixtures with different content of R-material in the asphalt mixture. It also deals with the description of functional tests of asphalt mixtures and the results of these tests.
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Performance Evaluation of Foamed Warm Mix Asphalt Produced by Water InjectionAli, Ayman W. 12 August 2013 (has links)
No description available.
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Vlastnosti asfaltových směsí typu SMA s R-materiálem / Properties of asphalt mixtures of SMA-type with RAPAcuna Subia, Luis Carlos January 2018 (has links)
The aim of the diploma thesis is to verify and compare the properties of bituminous stone mastic asphalt, namely SMA 11S with modified PMB 45 / 80-55 asphalt binder or 50/70 road bitumen binder with rubber granulate. Comparison of properties is performed using functional tests. The thesis is divided into the theoretical and practical part. The theoretical part deals with the familiarization with the use of the SMA mixture, the selected concepts concerning recycling of non-leveled roads are described and described. Attention is paid especially to the recycling of roads in the Czech Republic with an emphasis on hot recycling on the incinerator, which allows increased dosing of Reclaimed Asphalt into asphalt mixtures. In the practical part, the results of the functional tests of the SMA 11S mixture, which have been taken from the test section, are processed and evaluated.
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Využití technologie pěnoasfaltu / Usage of foam bitumen technologyMachel, Ondřej January 2019 (has links)
The diploma thesis deals with the production of warm mix asphalts, using the foam bitumen technology. The thesis is divided into theoretical and practical part. The theoretical part is focused on the basic division of roadway constructions, particularly on warm mix asphalts. The aim of the practical part was to find out whether the produced asphalt mixture retains its functional properties when the operating temperature is reduced. For this purpose, two asphalt mixtures of the ACO 11+ type at operating temperature of 150 °C and reduced operating temperature of 130 °C were made. Functional tests and empirical and functional tests were carried out on the produced asphalt mixtures and the extracted bitumen binders respectively. In the conclusion of the thesis, the results of the tests are mutually compared.
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Asfaltové směsi se zpěněným asfaltem / Foam asphalt mixturesBrtníková, Tereza January 2020 (has links)
The diploma thesis is divided into theoretical and practical part. The theoretical part is mainly focused on methods for reducing the working temperature in the production of hot mix asphalt and the main reasons for this. Most attention is paid to the warm mix asphalt, mainly foam asphalt technology. In practical part are describes working procedures of individual tests on asphalt mixtures and recovered bitumen binders. The tests were performed on 3 types of ACO 11+, one was made with working temperature 160°C without foamed bitumen and the other two with foamed bitumen,one with working temperature 160°C and the second 140°C. Then were the results compared.
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Navrhování nízkohlučných asfaltových směsí / Design of low-noise asphalt mixturesŘehulka, Martin January 2020 (has links)
The Master’s thesis is focused on low-noise asphalt mixtures in general, namely asphalt concrete for very thin layers with low noise (BBTM 8 NH) and stone mastic asphalt with low noise (SMA 8 NH). The first half of the thesis describes basic types of asphalt mixtures with low noise, requirements for raw materials (aggregates and asphalt), noise emissions and their measurement methods. The second part deals the design of BBTM 8 NH and SMA 8 NH so that they have the same voids. Subsequently, their parameters were tested. Acoustic absorption, resistence against permanent deformation and stiffness. Test methods are described and evaluated.
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Využití R-materiálu v krytových vrstvách vozovek / Usage of recycled material in asphalt surface layersMalá, Markéta January 2016 (has links)
Diploma thesis deals with adding R - material to the wearing asphalt courses, specifically to the SMA 11S. It has two parts – theoretical and practical. The theoretical part describes using R - material in the recycling of roads, different types of recycling and how is this problem handled in the Czech Republic, the practical part deals with the design of three kinds of asphalt mixtures with different added ratios of R – material, describing empirical and functional tests on the bitumen binder and the designed asphalt mixtures and the results of those tests.
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Využití R - materiálu v asfaltových kobercích mastixových / Usage of recycled material in stone mastic asphaltsSlavíček, Michal January 2017 (has links)
This diploma thesis deals with the designs of asphalt mixtures for the wearing asphalt courses, specifically for the SMA 11S with an added 30 % and 50 % RAP (reclaimed asphalt pavement), this material was reclaimed from the wearing asphalt course type SMA. The thesis is divided into two parts. The first part is theoretical and it deals with the recycling of asphalt roads and adding RAP to the new asphalt mixures for the roads. The second part is practical. It deals with the design itself. Two types of SMA were designed, first with a 30 % RAP and second with a 50 % RAP. In those mixtures functional tests of asphalt mixtures were made.The results were compared to the asphalt mixture with 0 % of RAP and with the mixture with 30 % of RAP reclaimed from the wearing, binder and base course together. The results are summed up in the conclusion.
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