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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Kotel na spalování dřeva s hnědým uhlí (váhový poměr 50/50),30t/h / Steam boiler for burnig mix of wood and sub-bituminous coal(mixing 50/50).35t/h

Chmelíček, Jiří January 2013 (has links)
This master´s thesis deals with the constructional and calculation design of the boiler for burning wood and sub-bituminous coal. The work is divided into several parts. First, stoichiometrics calculation and enthalpy calculations of air and flue gas are performed. It is calculated heat balance of the boiler, the boiler losses and the thermal efficiency of the boiler is determined. After designing the combustion chamber thermal calculation is made. Then, the dimensions and individual heating surfaces are proposed. At the end of the calculations are controlling the overall energy balance.
92

Des aménagements routiers sécuritaires et des techniques routières urbaines dans une perspective de gestion durable de la voirie : le cas du Québec / Safe road development and urban road technology from a sustainable road management perspective : the case of Quebec

St-Jacques, Michèle 16 May 2019 (has links)
Pendant plusieurs années, les aménagements de la voirie urbaine ont été adaptés à un accroissement continuel de la circulation automobile avec l’élargissement des emprises roulables et la prédominance du noir des revêtements bitumineux. Or, la route accueille maintenant des usagers variés. Elle doit donc tenir compte de tous ces utilisateurs, leur donner la place qui leur revient et réussir à les faire cohabiter. La route doit mettre en valeur les territoires qu’elle traverse, tout en répondant à sa mission première qui est de desservir adéquatement les communautés avoisinantes. Il faut concevoir des routes de façon à ce que les conducteurs de véhicules motorisés fassent naturellement ce qu’on attend d’eux. Les revêtements colorés peuvent être utilisés pour créer des ambiances urbaines, renforcer l’identité d’une ville et faciliter la lecture des espaces. Plusieurs nouveaux aménagements routiers, allant des carrefours giratoires aux stationnements en passant par la signalisation et toutes les mesures qui permettent de modérer la circulation, sont à la disposition des concepteurs. De plus, dans un contexte de développement durable, de nouvelles techniques routières ont fait leur apparition. Parmi celles-ci, en plus des revêtements colorés, il y a les enrobés tièdes. Cette thèse, basée sur une trentaine d’années de recherches, d’enseignements, de réalisations et d’observations à travers le monde, présente ces nouveaux aménagements routiers et ces nouveaux matériaux / For years, the development and maintenance of urban road systems responded to a continuous increase in automobile traffic by extending the network, with the blacktop for asphalt pavements taking the lead. However, the road now serves a wide variety of users, which it must now satisfy even as it struggles to meet their competing end goals. The road must enhance the landscape, while adequately serving the surrounding communities. Road design must be realized in a manner that allows drivers to perform what is expected of them naturally. Coloured bituminous surfaces can be used to create urban atmospheres, to reinforce the identity of a city, to facilitate the reading of spaces, to support the cohabitation of different users and to identify different places. Several new road engineering measures, such as roundabouts, parking, traffic signs and traffic calming measures, are now available to urban planners, traffic engineers and road designers. Furthermore, in the framework of sustainable development, new road techniques have emerged, including coloured bituminous pavements and a variety of warm mix asphalt techniques. This thesis, wich is based on thirty years of research, teaching, accomplishments and observations from around the world, presents these new road management measures and materials
93

Coal seam gas associations in the Huntly, Ohai and Greymouth regions, New Zealand

Butland, Caroline January 2006 (has links)
Coal seam gas has been recognised as a new, potential energy resource in New Zealand. Exploration and assessment programmes carried out by various companies have evaluated the resource and indicated that this unconventional gas may form a part of New Zealand's future energy supply. This study has delineated some of the controls between coal properties and gas content in coal seams in selected New Zealand locations. Four coal cores, one from Huntly (Eocene), two from Ohai (Cretaceous) and one from Greymouth (Cretaceous), have been sampled and analysed in terms of gas content and coal properties. Methods used include proximate, sulphur and calorifc value analyses; ash constituent determination; rank assessment; macroscopic analysis; mineralogical analysis; maceral analysis; and gas analyses (desorption, adsorption, gas quality and gas isotopes). Coal cores varied in rank from sub-bituminous B-A (Huntly); sub-bituminous C-A (Ohai); and high volatile bituminous A (Greymouth). All locations contained high vitrinite content (~85 %) with overall relatively low mineral matter observed in most samples. Mineral matter consisted of both detrital grains (quartz in matrix material) and infilling pores and fractures (clays in fusinite pores; carbonates in fractures). Average gas contents were 1.6 m3/t in the Huntly core, 4.7 m3/t in the Ohai cores, and 2.35 m3/t in the Greymouth core. The Ohai core contained more gas and was more saturated than the other cores. Carbon isotopes indicated that the Ohai gas composition was more mature, containing heavier 13C isotopes than either the Huntly or Greymouth gas samples. This indicates the gas was derived from a mixed biogenic and thermogenic source. The Huntly and Greymouth gases appear to be derived from a biogenic (by CO2 reduction) source. The ash yield proved to be the dominant control on gas volume in all locations when the ash yield was above 10 %. Below 10 % the amount of gas variation is unrelated to ash yield. Although organic content had some influence on gas volume, associations were basin and /or rank dependant. In the Huntly core total gas content and structured vitrinite increased together. Although this relationship did not appear in the other cores, in the Ohai SC3 core lost gas and fusinite are associated with each other, while desmocollinite (unstructured vitrinite) correlated positively with residual gas in the Greymouth core. Although it is generally accepted that higher rank coals will have higher adsorption capacities, this was not seen in this data set. Although the lowest rank coal (Huntly) contains the lowest adsorption capacity, the highest adsorption capacity was not seen in the highest rank coal (Greymouth), but in the Ohai coal instead. The Ohai core acted like a higher rank coal with respect to the Greymouth coal, in terms of adsorption capacity, isotopic signatures and gas volume. Two hypothesis can be used to explain these results: (1) That a thermogenically derived gas migrated from down-dip of the SC3 and SC1 drill holes and saturated the section. (2) Rank measurements (e.g. proximate analyses) have a fairly wide variance in both the Greymouth and Ohai coal cores, thus it maybe feasible that the Ohai cores may be higher rank coal than the Greymouth coal core. Although the second hypothesis may explain the adsorption capacity, isotopic signatures and the gas volume, when the data is plotted on a Suggate rank curve, the Ohai coal core is clearly lower rank than the Greymouth core. Thus, pending additional data, the first hypothesis is favoured.
94

Coal seam gas associations in the Huntly, Ohai and Greymouth regions, New Zealand

Butland, Caroline January 2006 (has links)
Coal seam gas has been recognised as a new, potential energy resource in New Zealand. Exploration and assessment programmes carried out by various companies have evaluated the resource and indicated that this unconventional gas may form a part of New Zealand's future energy supply. This study has delineated some of the controls between coal properties and gas content in coal seams in selected New Zealand locations. Four coal cores, one from Huntly (Eocene), two from Ohai (Cretaceous) and one from Greymouth (Cretaceous), have been sampled and analysed in terms of gas content and coal properties. Methods used include proximate, sulphur and calorifc value analyses; ash constituent determination; rank assessment; macroscopic analysis; mineralogical analysis; maceral analysis; and gas analyses (desorption, adsorption, gas quality and gas isotopes). Coal cores varied in rank from sub-bituminous B-A (Huntly); sub-bituminous C-A (Ohai); and high volatile bituminous A (Greymouth). All locations contained high vitrinite content (~85 %) with overall relatively low mineral matter observed in most samples. Mineral matter consisted of both detrital grains (quartz in matrix material) and infilling pores and fractures (clays in fusinite pores; carbonates in fractures). Average gas contents were 1.6 m3/t in the Huntly core, 4.7 m3/t in the Ohai cores, and 2.35 m3/t in the Greymouth core. The Ohai core contained more gas and was more saturated than the other cores. Carbon isotopes indicated that the Ohai gas composition was more mature, containing heavier 13C isotopes than either the Huntly or Greymouth gas samples. This indicates the gas was derived from a mixed biogenic and thermogenic source. The Huntly and Greymouth gases appear to be derived from a biogenic (by CO2 reduction) source. The ash yield proved to be the dominant control on gas volume in all locations when the ash yield was above 10 %. Below 10 % the amount of gas variation is unrelated to ash yield. Although organic content had some influence on gas volume, associations were basin and /or rank dependant. In the Huntly core total gas content and structured vitrinite increased together. Although this relationship did not appear in the other cores, in the Ohai SC3 core lost gas and fusinite are associated with each other, while desmocollinite (unstructured vitrinite) correlated positively with residual gas in the Greymouth core. Although it is generally accepted that higher rank coals will have higher adsorption capacities, this was not seen in this data set. Although the lowest rank coal (Huntly) contains the lowest adsorption capacity, the highest adsorption capacity was not seen in the highest rank coal (Greymouth), but in the Ohai coal instead. The Ohai core acted like a higher rank coal with respect to the Greymouth coal, in terms of adsorption capacity, isotopic signatures and gas volume. Two hypothesis can be used to explain these results: (1) That a thermogenically derived gas migrated from down-dip of the SC3 and SC1 drill holes and saturated the section. (2) Rank measurements (e.g. proximate analyses) have a fairly wide variance in both the Greymouth and Ohai coal cores, thus it maybe feasible that the Ohai cores may be higher rank coal than the Greymouth coal core. Although the second hypothesis may explain the adsorption capacity, isotopic signatures and the gas volume, when the data is plotted on a Suggate rank curve, the Ohai coal core is clearly lower rank than the Greymouth core. Thus, pending additional data, the first hypothesis is favoured.
95

Estudo comparativo das características físicas e mecânicas de agregados graúdos convencional e não convencionais visando suas aplicações em Concreto Betuminoso usinado à quente. / Comparative study of the physical and mechanical characteristics of conventional and unconventional heavy aggregates for their applications in hot-rolled Bituminous Concrete.

MACÊDO, José Afonso Gonçalves de. 30 September 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-30T13:20:44Z No. of bitstreams: 1 JOSÉ AFONSO GONÇALVES DE MACÊDO - DISSERTAÇÃO PPGECA 1989..pdf: 62874473 bytes, checksum: fb1fdb8f43a121e308d6bbcf739a30b1 (MD5) / Made available in DSpace on 2018-09-30T13:20:44Z (GMT). No. of bitstreams: 1 JOSÉ AFONSO GONÇALVES DE MACÊDO - DISSERTAÇÃO PPGECA 1989..pdf: 62874473 bytes, checksum: fb1fdb8f43a121e308d6bbcf739a30b1 (MD5) Previous issue date: 1989-08-31 / Este trabalho faz parte de um estudo mais amplo que visa a utilização de agregados graúdos não convencionais para a obtenção de misturas betuminosas e concreto de cimento Portland. Sendo concebido a partir de estudos já iniciados por outros pesquisadores, que estudaram comparativamente agregados graúdos calcários e lateríticos com um agregado graúdo granítico, visando suas utilizações em concreto betuminoso usinado ã quente. Nesta pesquisa os agregados são avaliados em laboratório,a partir de suas características físicas e mecânicas bem como fa zendo parte de um concreto betuminoso fabricado com teores de ligante determinados a partir dos estudos iniciados por Brasileiro, (1983). Também são verificadas as variações ocorridas com a absorção e massa específica dos agregados graúdos, antes e após a confecção dos corpos de prova pelo ensaio Marshall. Os resultados obtidos permiter.; concluir que, embora tenham sido obtidos em laboratório, existem boas perspectivas de utilização dos agregados lateríticos e calcários para fabricação de concreto betuminoso usinado ã quente, restando ainda, entre outras coisas, melhor adaptação da metodologia de ensaio para avaliação destes materiais e, a execução de trechos experimentais para verificar seus comportamentos em serviços. / This research, which is part of a more comprehensive study on non conventional materials, aims to utilize coarse aggregates for bituminous mixtures and concrete of Portland cement. Previous studies carried out by several investigators, have shown thorough comparative studies the feasibility of calcareous, laterite and granite coarse aggregates for hot-mix bituminous concrete. The aggregates utilized in this research are avaluated in the laboratory by its physical and mechanical characteristics.As well as in samples of bituminous concrete with binder contents, as determined by Brasileiro (1983). Also, it has been verified variations on the absorption and specific gravity of coarse aggregates, before and after the compaction of samples for Marshall test. The laboratory test results concluds that, there are good perspectives to utilize lateritic and calcareous aggregates for hot-mix bituminous concrete. Further research is needed to find the best testing methodology in order to evaluate these materials, and to construct trial pavements to verify its field behaviour.
96

Asfaltové směsi s použitím vyššího množství R-materiálu / Asphalt mixtures with the use of higher amount of RAP

Mucha, 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.
97

Geology and characterization of coal at the Mushithe Coal Occurrence, Soutpansberg Coalfield, Limpopo Province, South Africa

Mukatuni, Sedzani 20 September 2019 (has links)
MESMEG / Department of Mining and Environmental Geology / The Mushithe coal occurrence is situated approximately 16 km west of the Tshikondeni coal mine in the Tshipise-Pafuri sub-basin of the Soutpansberg coalfield in South Africa. The Soutpansberg Coalfield has received comparatively less attention compared to other more notable South African coalfields. There is as a consequence very limited information in the public domain applicable to the geology as well as quality of coal in this coalfield, as a result there is no known study focused exclusively on the Mushithe coal occurrence. The aim of the study was to conduct detailed geological mapping of the Mushithe Deposit so as to ascertain the geological environment and petrological characteristics of rocks within the area. Further work involved coal sampling and analysis in order to establish coal quality and its physical and chemical characteristics. Samples were collected using geological field mapping and channel sampling. Nine coal samples were collected from the coalbed and host rock, exposed along the Mbodi River, during geological field mapping using channel sampling. Furthermore, 92 rock samples were collected during geological field mapping of which 10 representative samples were selected for further analysis. X-ray fluorescence spectrometry was conducted on all selected samples. Proximate analysis and ultimate analyses, and calorimetry tests were undertaken on coal samples. Three samples were selected based on calorific value for maceral identification, mineral analyses and vitrinite reflectance using petrographic study. Detailed geological mapping of the area around the Mushithe coal occurrence showed the geological setting of coal in this area. The following lithologies were identified in the study area: sandstone, mudstone, ironstone, calcrete, shale, quartzite, quartz vein with a general strike direction to the north-east. The host rocks including coal were intruded by dolerite dykes and this resulted in the devolatilization of coal. The current study concluded that the Mushithe coal was formed in a wet swampy environment. This has been confirmed based on tissue preservation index (1.69) and gelification index (2.35). Coal rank ranged from bituminous Rank C- B according to United Nations Economic Commission for Europe Coal Classification (UNECE) and samples were characterised by high ash (27.90%), high moisture (10.47%) and low sulphur (0.24%). Furthermore, coal was graded below grade D based on classification for use by ESKOM which consider any calorific value below 24.5 MJ/kg to be in this category. The coal is vitrinite rich (77.75 vol%) and low in Inertinite (22.25 vol%) and devoid of Liptinite and pseudovitrinite, thus it is of good coking quality. Geochemical analysis revealed that the coal was enriched in TiO2 and Fe2O3 which was corroborated by the mineral matter which was mostly clay and pyrite. Comparatively, coal quality analysis revealed the calorific value of 14.26 MJ/kg and vitrinite reflectance between 0.94 %ROV to 1 %ROV which was less than that of the Tshikondeni Deposit but greater than that at Waterberg coalfield. The study recommends further detailed exploration of coal in the area, applying such techniques such as geophysical exploration and borehole drilling leading to resource evaluation. Further studies are recommended to provide a better interpretation of the depositional environment of coal at Mushithe as well as the effect of devolatilaziton by a dolerite dyke. / NRF
98

Évaluation des performances thermomécaniques des enrobés bitumineux à fort taux de recyclage : Apport du procédé de régénération Fenixfalt / Evaluation of the thermo mechanical performances of bituminous mixes with high recycling rates. Contribution of Fenixfalt rejuvenation process.

Alvarado patino, Nelson Andrey 05 December 2018 (has links)
Une étude expérimentale a été effectuée sur diverses formules de trois familles d’enrobés bitumineux avec des taux de recyclage variables et la présence ou non de régénérant. La composition des mélanges et le procédé de fabrication ont été élaborés afin d’effectuer une étude comparative. L’enrobage produit des variations des paramètres physico-chimiques des liants telles que la consistance, la température de transition vitreuse, les fractions cristallisables, les taux d’aromatiques et d’asphaltènes ; ces variations sont limitées en présence de régénérant. Lorsque le taux d’AE augmente, la compactibilité et l’orniérage des mélanges diminuent et leur rigidité viscoélastique augmente, mais le régénérant limite ces variations. Globalement, les AE produisent une augmentation de la résistance à la fatigue des formules et un aplatissement des droites de Wöhler. Le régénérant améliore le paramètre de fatigue ɛ6 ; les performances en fatigue augmentent avec la TBA et l’indice colloïdal du liant ainsi qu’avec la diminution de la viscosité de l’enrobé. L’impact favorable d’un taux élevé d’AE et du régénérant sur le trafic admissible a été déterminé suite au dimensionnement d’une structure souple tri-couche. À basse température, la détérioration par les AE de la ductilité en traction et de la température de rupture par retrait empêché se trouvent limitées par le régénérant ; un compromis est cependant à trouver avec la résistance à la fatigue. Les formules régénérées mises en œuvre sur la couche de roulement d’une route départementale ont subi une moindre évolution après six ans de service que les mélanges non régénérés. / An experimental programme has been performed on three types of bituminous mixes with variable recycling rates and the possible addition of rejuvenator. The mix composition and the production process have been defined in order to perform a comparative analysis. The coating process modifies the physico-chemical parameters of the binders, like consistency, glassy transition temperature, cristallizable moiety, aromatics and asphaltenes rates; the above variations are limited by using the rejuvenator. As the RAP content increases, the compactibility and the rutting of the mixes decrease and the viscoelastic stiffness increases, but the rejuvenation reduces these variations. Globally, RAP increases the fatigue resistance of the mixes and flattens the Wöhler curve. Rejuvenation enhances ɛ6 fatigue parameter; fatigue performances increase with R&B temperature and colloidal index of the binder and as the viscous component of the mixes decreases. The positive impact of a high rate of RAP and of the rejuvenation on the allowable traffic has been evaluated from the structural design of a threelayered pavement. At low temperature, the deterioration of the tension ductility and of the stress restrained failure temperature produced by the RAP, is limited by the rejuvenation; a compromise with the fatigue resistance has to be found. The rejuvenated mixes laid as surface layers on a provincial road have experienced a smaller evolution that non rejuvenated mixes.
99

Étude thermomécanique avancée de différents types d’enrobés recyclés tièdes avec additifs / Advanced thermomechanical study of different types of warm recycled asphalt with additives

Pham, Nguyen Hoang 12 December 2014 (has links)
Cette thèse s’inscrit dans le cadre d’une collaboration entre le Laboratoire Génie Civil et Bâtiment (LGCB)/Laboratoire de Tribologie et Dynamique des Systèmes (LTDS) et l’entreprise Arkema, l’entreprise routière Malet, l’Agence de l’Environnement et de la Maîtrise de l’Énergie (ADEME). L’objectif de la thèse est l’étude du comportement thermomécanique des enrobés bitumineux, et spécifiquement les enrobés tièdes avec et sans agrégat d’enrobé (RAP, Reclaimed Asphalt Pavement), dans le but de prévoir leur durée de vie et d’optimiser leur dimensionnement dans un contexte de développement durable.Sept types d’enrobés bitumineux sont étudiés. Les enrobés diffèrent par leur procédé de fabrication, le pourcentage de RAP, les additifs et le pourcentage d’additif utilisé. Deux types de fabrications sont étudiées : à chaud (Hot Mix –HM) qui sert de référence et tièdes (Warm Mix –WM). Trois pourcentages de RAP sont considérés : 0%, 30% et 50%. Deux types d’additifs fournis par ARKEMA sont utilisés, ETIMA (E) et ETIMA-BIO (B), avec deux pourcentages, 0% et 0.4%. L’utilisation des enrobés tièdes contribue à réduire considérablement la consommation d’énergie, l’impact sanitaire et l’impact environnemental. D’autre part, l’ajout des RAP dans les enrobés permet d’augmenter le taux de recyclage des matières non renouvelables. Ces innovations participent à la prise en compte des enjeux du développement durable et de la préservation de l’environnement.Quatre types d’essais ont été réalisés. Ce sont : l’essai de module complexe, l’essai de fatigue, l’essai de retrait thermique empêché (TSRST) et l’essai de propagation d’ondes. Dans le domaine du comportement viscoélastique linéaire, les essais de module complexe sont réalisés sur une large gamme de températures (de -25°C à 45°C) et de fréquences (de 0.03Hz à 10Hz). Chaque test est dupliqué. Les résultats sont modélisés à l’aide du modèle analogique 2S2P1D qui a été développé au laboratoire LGCB de l’ENTPE. Ce modèle permet de modéliser correctement le comportement tridimensionnel viscoélastique linéaire des enrobés. Ensuite, le comportement en fatigue est étudié grâce à des essais de fatigue. Pour chaque matériau, quatre ou cinq éprouvettes sont testées. Quatre critères sont utilisés pour évaluer la durée de vie des matériaux. Puis, le comportement à basse température est caractérisé à l’aide de l’essai de retrait thermique empêché (TSRST). Pour chaque matériau, trois éprouvettes sont testées. Enfin, des essais de propagation d’ondes sont réalisés. La méthode de détermination du temps de vol des ondes « P » et des ondes « S » ainsi que la méthode Impact Résonance sont utilisées. Ces essais fournissent des mesures non destructives et faciles à réaliser. A partir de ces méthodes, on peut calculer les valeurs de modules et de coefficients de Poisson des matériaux.Soulignons que les essais réalisés permettent d’obtenir certain des paramètres utilisés pour le dimensionnement des chaussées. Un résultat essentiel de l’étude est la bonne performance des enrobés tièdes contenant des agrégats d’enrobés (RAP). / This PhD dissertation is part of the collaboration between the French Agency for Environment and Energy Management (ADEME), the companies Arkema and Malet and the Ecole Nationale de Travaux Publics de l’Etat (ENTPE). The aim of this dissertation is to study the thermo-mechanical behavior of asphalt mixes, specifically warm mix asphalts with and without Reclaimed Asphalt Pavement (RAP) in order to predict their fatigue life and to optimize their design by targeting sustainable development. Seven types of asphalt mixes are studied. They differ in their mixing method, RAP content, additives used and their content. Two types of mixing methods are studied: Hot Mix Asphalt (HMA), which serves as a reference, and Warm Mix Asphalt (WMA). Three RAP contents are considered: 0%, 30% and 50%. Two types of additives provided by Arkema are used : ETIMA (E) and ETIMA-BIO (B) with two contents for each of them (0% and 0.4%). The use of warm mix asphalt helps significantly reducing both energy consumption and the impact on health and environment. These innovations are significant contributions with respect to issues of sustainable development and environmental preservation. Four types of laboratory tests were performed: complex modulus tests, fatigue tests, Thermal Stress Restrained Specimen Tests (TSRST) and wave propagation tests. In the Linear ViscoElastic (LVE) behavior domain, complex modulus tests were performed on a wide range of temperatures (from -25°C to 45°C) and frequencies (from 0.03 Hz to 10 Hz). For each material, two specimens were tested. Values of complex modulus and complex Poisson’s ratio were obtained and modeled using the 2S2P1D analogies model, developed in the Laboratoire Génie Civil et Bâtiement (LGCB) of ENTPE. It was observed that this model can correctly simulate the LVE behavior of asphalt mixes. Fatigue behavior was studied by analyzing fatigue tests results. For each material, four or five specimens were tested. Four different failure criteria were used in order to evaluate fatigue life of materials. Low temperature behavior of materials was characterized using TSRST. For each material, three replicates were performed. Finally, wave propagation tests were carried out. The method to determine the time of flight of « P » and « S » waves and the impact resonance method are presented. These tests provide a non-destructive method to characterize materials, which easy to perform. Using those methods, values of complex modulus and Poisson's ratio of tested materials can be estimated. It is to be underlined that the tests performed in this PhD allow to obtaining some parameters which are required for asphalt pavement design. An important result obtained in this study is that warm mix asphalt combined with RAP and additives (ETIMA ou ETIMA-BIO) could perform as well as hot mix asphalt.
100

Applications of Solid-Phase Microextraction to Chemical Characterization of Materials Used in Road Construction

Tang, Bing January 2008 (has links)
Environmental and health aspects of road materials have been discussed for a long time, mostly regarding bitumen and bitumen fumes. However, just a few studies on other types of road materials have been reported. In this doctoral study, two types of materials, asphalt release agents and bituminous sealants, were investigated with regard to chemical characterization and emission profiles. Besides conventional test methods, solid-phase microextraction (SPME) technique was applied for emissions profiles screening and quantitative analysis. General description of main characteristics of asphalt release agents and bituminous sealants is given, and a comprehensive state-of-the-art on SPME technique is presented, especially on methodologies for analyzing mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs) in different sample matrices. In the experimental study, chemical characterization of the two material types was performed using conventional methods, including fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR), gel permeation chromatography (GPC), mass spectrometry (MS) and gas chromatography – mass spectrometry (GC-MS). General patterns regarding functional groups and molecular weight distribution were studied. In the case of asphalt release agents, more detailed information on chemical compositions, especially the contents of MAHs and PAHs, was obtained. General information on emission proneness of asphalt release agents was obtained using thermogravimetric analysis (TGA) and MS. Using headspace(HS)-SPME and GC-MS, emission profiles of asphalt release agents were characterized at different temperatures, whereas the profiles of bituminous sealants were obtained solely at room temperature. The results presented were used for ranking the materials with regard to degree of total emission as well as emission of hazardous substances. The applicability of HS-SPME for quantitative analysis of MAHs in asphalt release agents and emulsion-based bituminous sealants was investigated. The use of a surrogate sample matrix was concerned, and experimental parameters influencing the HS-SPME procedure, such as equilibration and extraction time, as well as effects of sample amount and matrices, were studied. The methods were evaluated with regard to detection limit, accuracy as well as precision. Different calibration approaches including external calibration, internal calibration and standard addition were investigated. The determination of MAHs in asphalt release agents and emulsion-based bituminous sealants using HS-SPME-GC-MS was conducted. / QC 20100913

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