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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.
911

Water Fluxes in Soil-Pavement Systems: Integrating Trees, Soils and Infrastructure

de la Mota Daniel, Francisco Javier 31 January 2019 (has links)
In urban areas, trees are often planted in bare soil sidewalk openings (tree pits) which recently are being covered with permeable pavements. Pavements are known to alter soil moisture and temperature, and may have implications for tree growth, root development and depth, drought resilience, and sidewalk lifting. Furthermore, tree pits are often the only unsealed soil surface and are important for water exchange between soil and atmosphere. Therefore, covering tree pits with pavement, even permeable, may have implications for the urban water balance and stormwater management. A better understanding of permeable pavement on tree pavement soil system functioning can inform improved tree pit and street design for greater sustainability of urban environments. We conducted experiments at two sites in Virginia, USA (Mountains and Coastal Plain) with different climate and soil. At each location, we constructed 24 tree pits in a completely randomized experiment with two factors: paved with resin-bound porous-permeable pavement versus unpaved, and planted with Platanus x acerifolia 'Bloodgood' versus unplanted (n = 6). We measured tree stem diameter, root growth and depth, and soil water content and temperature over two growing seasons. We also monitored tree sap flow one week in June 2017 at the Mountains. In addition, we calibrated and validated a soil water flow model, HYDRUS-1D, to predict soil water distribution for different rooting depths, soil textures and pavement thicknesses. Trees in paved tree pits grew larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to the increased soil water content and the extended root growing season (14 more days). Tree transpiration was 33% of unpaved and planted pit water outputs, while it was 64% for paved and planted pits. In June 2016, planted pits had decreased root-zone water storage, while unplanted pits showed increased storage. A water balance of the entire experimental site showed overall decreased soil water storage due to tree water extraction becoming the dominant factor. HYDRUS-1D provided overall best results for model validation at 10 cm depth from soil surface (NSE = 0.447 for planted and paved tree pits), compared to 30- and 60 cm depths. HYDRUS-1D simulations with greater pavement thickness resulted in changes in predicted soil water content at the Coastal Plain, with higher values at 10- and 30-cm depths, but lower values at 60-cm depth. At the Mountains, virtually no difference was observed, possibly due to different soil texture (sandy vs clayey). Tree pits with permeable pavement accelerated tree establishment, but promoted shallower roots, possibly increasing root-pavement conflicts and tree drought susceptibility. Paved tree pits resulted in larger trees, increasing tree transpiration, but reduced soil evaporation compared to unpaved pits. Larger bare soil pits surrounded by permeable pavement might yield the best results to improve urban stormwater retention. Also, HYDRUS 1D was successful at simulating soil water content at 10-cm depth and may be valuable to inform streetscape design and planning. / PHD / Trees in cities are often planted in pavement cutouts (tree pits) that are usually the only available area for water exchange between soil and atmosphere. Tree pits are typically covered with a variety of materials, including permeable pavement. Pavements are known to modify soil water distribution and temperature, affecting tree growth, rooting depth, drought resilience, and sidewalk lifting. A better understanding of this system can inform tree pit and street design for greater sustainability. We constructed 24 tree pits at each of two regions in Virginia, USA (Mountains and Coastal Plain). These tree pits were paved with permeable pavement or unpaved, and planted with London Plane or unplanted. We measured stem diameter, root growth, and soil water content and temperature over two years and tree sap flow for one week in summer (Mountains only). We also used a soil water flow model, HYDRUS-1D, to predict water distribution for different rooting depths, soil textures and pavement thicknesses. After the first growing season trees in pavement were larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to increased soil water content and a 14-day increase in root growing season. Also, in June 2017, tree transpiration was 33% of unpaved-and-planted pit water outputs, and 64% of paved-and-planted pits. In June 2016, root-zone water storage decreased in planted pits but increased in unplanted pits. When considering the entire experimental site, soil water storage decreased, with tree water extraction being the dominant factor. HYDRUS-1D performed better at 10-cm soil depth than at 30- and 60-cm depths. At the Coastal Plain, HYDRUS-1D predicted higher soil water content at 10- and 30-cm depths with increased pavement thickness, but lower values at 60-cm depth. At the Mountains, there was no effect, possibly due to higher clay content. Permeable pavement accelerated tree establishment, but promoted shallower roots, increasing drought susceptibility and risk for root-pavement conflicts. Pavement resulted in larger trees and greater transpiration, but reduced soil evaporation. Larger bare-soil pits surrounded by permeable pavement might optimize stormwater retention.
912

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.
913

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.
914

Investigating the Need for Drainage Layers in Flexible Pavements

Masoud Seyed Mohammad Ghavami (6531011) 10 June 2019 (has links)
<p>Moisture can significantly affect flexible pavement performance. As such, it is crucial to remove moisture as quickly as possible from the pavements, mainly to avoid allowing moisture into the pavement subgrade. In the 1990s the Indiana Department of Transportation (INDOT) adopted an asphalt pavement drainage system consisting of an open-graded asphalt drainage layer connected to edge drains and collector pipes to remove moisture from the pavement system.</p> <p>Over the intervening two decades, asphalt pavement materials and designs have dramatically changed in Indiana, and the effectiveness of the pavements drainage system may have changed. Additionally, there are challenges involved in producing and placing open-graded asphalt drainage layers. They can potentially increase costs, and they tend to have lower strength than traditional dense-graded asphalt pavement layers. </p> <p>Given the potential difficulties, the overall objective of this research was to evaluate the effectiveness of the INDOT’s current flexible pavement drainage systems given the changes to pavement cross-sections and materials that have occurred since the open-graded drainage layer was adopted. Additionally, the effectiveness of the filter layer and edge drains were examined.</p><p><br>Laboratory experiments were performed to obtain the hydraulic properties of field-produced asphalt mixture specimens meeting INDOT’s current specifications. The results were used in finite element modeling of moisture flow through pavement sections. Modeling was also performed to investigate the rutting performance of the drainage layers under various traffic loads and subgrade moisture conditions in combination with typical Indiana subgrade soils. The modeling results were used to develop a design tool that can assist the pavement designer in more accurately assessing the need for pavement drainage systems in flexible pavements.<br></p>
915

Propriétés thermomécaniques d’enrobés multi-recyclés / Thermomechanical propertis of bitiminous mixtures multi-recycled

Pedraza, Alvaro 06 March 2018 (has links)
Les premiers recyclages d’enrobés bitumineux à 50% sont apparus sur autoroutes françaises dans les années 1990 – une charte de l’innovation spécifique aux enrobés drainants intégrant 50% de recyclés fut notamment délivrée début 2002 (SETRA - CSTR, 2002). Un nouveau cycle de recyclage à fort taux de ces tout premiers enrobés a été entrepris ici ou là, depuis quelques années. Le multirecyclage des agrégats d’en-robé (AE) dans les mélanges d’enrobés bitumineux est de ce fait une problématique actuelle, qui va se gé-néraliser dans l’avenir, lorsqu’il faudra recycler des enrobés contenant déjà des enrobés recyclés plusieurs fois. Le projet visant à étudier le MUlti-Recyclage des Enrobés tièdes a été labellisé projet national (PN MURE). Une part du projet MURE regroupant des aspects scientifiques particuliers a été regroupé au sein du projet « IMPROVMURE », financé par l’Agence Nationale de la Recherche, et qui a débuté en mars 2014. L’objectif du projet « Innovation en Matériaux et PROcédés pour la Valorisation du MUlti-Recyclage des En-robés » (IMPROVMURE) est de fournir des éléments de réponse raisonnés et quantifiés, en laboratoire et sur sites pilotes, afin de faire du multi-recyclage des enrobés fabriqués à chaud et tiède. Les questions sociétales, environnementales, règlementaires ou normatives sont également prises en compte dans le cadre du projet. Un des objectifs du projet IMPROVMURE est l’étude des propriétés thermomécaniques des enrobés. C’est dans le cadre de cet objectif que s’inscrit le travail de thèse présenté dans ce document. Cette thèse est le fruit d’une collaboration entre le Laboratoire Génie Civil et Bâtiment de l’ENTPE (LGCB)/Laboratoire de Tribologie et Dynamique des Systèmes (LTDS) et l’entreprise EIFFAGE Infrastructures. 15 types d’enrobés ont été testés pour l’étude des propriétés thermomécaniques des enrobés multi-recyclés. Les enrobés diffèrent par leur condition de fabrication (Laboratoire ou chantier), leur procédé de fabrication (chaud ou tiède mousse), le taux d’agrégat d’enrobé introduit (0%, 40%, 70% ou100%) et le nombre de cycles de recyclage (un, deux ou trois). Trois caractéristiques ont été communes à tous les types d’enrobés fabriqués, sauf pour l’enrobé contenant 100% d’agrégats d’enrobé. La première est la même courbe granulométrique des granulats, la troisième est la teneur en liant de 5.4% en masse et la troisième est le type d’enrobé « Béton Bitumineux Semi-Grenu » (BBSG) de type 03 selon la norme EN 13108-1. Trois domaines du comportement des enrobés bitumineux ont été étudies : Viscoélasticité linéaire (VEL), couplage thermomécanique à basse température et fissuration à froid. Pour le domaine de comportement VEL, les enrobés bitumineux ont été étudiés à l’aide des essais de module complexe en traction-compression réalisés sur une large gamme de températures et de fréquences sur éprouvette cylindrique à l’ENTPE. Les résultats sont modélisés à l’aide du modèle analogique 2S2P1D qui a été développé au laboratoire LGCB de l’ENTPE. Des essais de propagation d’ondes ont aussi été réalisés. La méthode de détermination du temps de vol des ondes « P » et des ondes « S » et la méthode Impact Résonance sont utilisées. Ces essais utilisent des méthodes non destructives et faciles à réaliser. On peut ainsi calculer les valeurs de modules et de coefficients de Poisson des matériaux. Puis, le couplage thermomécanique à basse température est caractérisé à l’aide de l’essai de retrait thermique empêché (TSRST), qui utilise le même dispositif que l’essai de module complexe mais les éprouvettes utilisées sont de géométrie différente. Finalement des essais de propagation de fissure ont été réalisés avec des sollicitations monotones. La propagation de la fissure suivie utilisant la méthode de corrélation des images. Des estimations de la hauteur de fissure ont été faites sur la basse de la méthode DRCL développée à l’ENTPE. / Reuse of Reclaimed Asphalt Pavement (RAP) is considered as one of the main solutions to cope with the objectives of worldwide sustainable development. In this way, the reuse of RAP in bituminous mixtures has been matter of study in previous papers (Chen et al., 2009; Kaur et al., 2013; Mogawer et al., 2012; Ru-bio et al., 2012; Sias Daniel et al., 2013; Valdés et al., 2011) and had concluded be economically profitable as well as had demonstrated the durability of the tested materials. Nowadays, new topics overcome dealing with how increase the RAP content and how many times RAP could be recycled. In France, a collaborative research and development project called “Multi-recycling of warm foam bitu-minous mixtures” (MURE) have brought together all the stakeholders involved in road construction. The pro-gram has run since March 2014. The scientific part of MURE project is IMPROVMURE project (Innovation for Materials and Processes for Improving the Multi-Recycling of Mixes). The overall budget of the project were €4.7M, €2.3M of which been provided by the ANR (National Re-search Agency) in the framework of the IMPROVMURE project, which has gotten under way in March 2014 and its main goal of characterizing the remobilization of the binder from recycled materials was the evalua-tion of the durability of mixes with the addition of binder. Thus, one objective of this project is to determine the thermomechanical properties of multi-recycled bi-tuminous mixtures, so in the context of this goal the current study was made. Likewise this investigation was a collaboration between the Tribology and System Dynamics Laboratory (LTDS) of the University of Lyon/ENTPE (“Ecole Nationale des Travaux Publics de l’Etat” ) and the French company EIFFAGE Infra-structures. For this study 15 types of bituminous mixtures were tested, the bituminous mixtures were produced in the laboratory and construction site, also two different techniques were studied for mixtures elaboration: hot and warm using foamed bitumen in both cases, the RAP content on these were 0%, 40%, 70% and even close to 100% produced after several recycling operations (up to 3 cycles). All bituminous mixtures have 3 invariants: the first is the same aggregate grading curves (except the bituminous mixture with 100% of RAP). The second one is the total binder content (5.4% in total weight). The last is classified as BBSG-03 0/10 bitu- 15 minous mixture, as is specified in the European standards for classification of bituminous mixtures (NF EN 13108-1 - 2007). Three domains of behaviour were studied: Linear Viscoelastic behaviour (LVE), cracking behaviour at low temperature and the fracture behaviour at low temperature. The LVE was studied considering complex modulus tests on bituminous mixtures and were performed in tension/compression on cylindrical samples, thus LVE behaviour was then modelled with 2S2P1D rheological model, developed at Uni. of Lyon / ENTPE, for the other hand cracking behaviour at low temperature was studied considering Thermal Stress Restrained Specimen Tests (TSRST), and finally fracture behaviour at low temperature was studied with the crack propagation tests as a monotonic loading.
916

Asfaltové směsi s vyšší životností za použití R-materiálu / Bituminous mixtures with a higher lifetime using recycled asphalt

Stromecký, Roman January 2019 (has links)
This diploma thesis deals with a project of asphalt mixtures with high stiffness modulus using R-material. The theoretical part describes the characteristics of these mixtures in the Czech Republic and in Switzerland. Further this part deals with the use of R-material in the Czech Republic and chosen other countries of the world, it also deals with the ways of recycling roads. The theoretical part also deals with the testing methods used. In the practical part two new asphalt mixtures of the high stiffness modulus type with the addition of 25 % R-material are suggested. As a base for these two mixtures a mixture of the high stiffness modulus type, which was taken from an asphalt mixing plant, was used. Tests were run on the binders and several functional tests (stiffness modulus, fatigue resistance, low temperature qualities) wer done on the suggested asphalt mixtures and also the mixture taken from the mixing plant. Consequently, the results were compared. The conclusion of the thesis is devoted to modelling a construction of a road using the program LayEps, which verified if the suggested mixtures could reduce the thickness of roads.
917

Inovativní asfaltové směsi pro netuhé vozovky s použitím R-materiálu / Inovative asphalt mixtures to flexible pavement structure with using reclaimed asphalt

Horáček, Daniel January 2020 (has links)
The diploma thesis is focused on the design and production of two innovative asphalt mixtures of the VMT 22 type into the base asphalt course. The newly produced blends contain modified binders, such as polymer modified bitumen (PMB) and Crumb rubber modified bitumen (CRMB). The theoretical part of the thesis describes the current state of the use of Reclaimed asphalt pavement in the base asphalt course. Furthermore, there are described types of asphalt mixtures for the base asphalt course are used in the Czech Republic and other countries. The conclusion of the theoretical part is devoted to the description of Reclaimed asphalt pavement (RAP), its storage and processing in a hot mix center. In the practical part of this thesis, there is described design and test of two High modulus asphalt mixture VMT 22, into which 25% RAP is dosed cold without rejuvenators. These asphalt mixtures are then subjected to functional tests (Stiffness of asphalt mixture test, Resistance to fatigue test, Low temperature properties of asphalt mixture test). The results of the functional tests are compared with the functional requirements in the Czech regulation TP 151. In the end of this thesis it is verified by means of the LayEps software that a suitable design of the asphalt mixture can significantly extend the road life.
918

Variantní řešení MÚK Mohelnice sever / Grade-separated interchange Mohelnice-north - Study

Lukáš, Radek January 2019 (has links)
This diploma thesis deals with the proposal of an alternative solution to the intersection of Mohelnice North crossroads. It compares the current junction design, which is considered inappropriate, with two new proposals for circular intersections. The aim of the thesis is to propose the resultant junction cheaper, smaller and simpler for users.
919

Využití asfaltových a betonových recyklátů do pozemních komunikací / The utilization of the asphalt and concrete recycled materials to roads

Žďára, Zbyněk Unknown Date (has links)
This diploma thesis is divided into two parts, theoretical and practical. The is a review om the topic of recycled asphalt pavement and recycled concrete and their possible use in road construction in the theoretical part. The individual chapters deal with describing these materials, their production, and their use in construction layers of pavements. In the next chapters the attention is also paid to their problematic features and foreign experience using these materials in pavements. In the practical part, laboratory samples of recycled asphalt pavement and recycled concrete and their mixtures with cement are tested. The main purpose is to verify the applications of these mixtures of recycled asphalt pavement and recycled concrete in the bonded base layers of the pavement. Another purpose is to compare how these mixtures individual properties with different proportions of both components and different amounts of cement will be different. In the end, the two mixtures with the best properties was selected and the modulus of elasticity was experimentally determined for the possibility of replacing the currently used base layers and the economic evaluation of this design was made.
920

Charakteristické vlastnosti směsných recyklátů pro spodní stavbu pozemních komunikací / Characteristics of mixed building recyclates for subgrade og roads

Junek, Lumír Unknown Date (has links)
The work deals with the use of mixed construction recycled material for earth bodies of roads. The theoretical part describes the production, usability and economic evaluation of recycled building materials against common natural materials. It then describes the necessary laboratory tests that examine its properties for the use of these materials in roads. In the last chapter, the work deals with foreign experience with the use of mixed construction recyclates for transport construction. The practical part examines the properties of the given recyclates for their use in the core using tests of soil freezing rate, California bearing ratio and immediate bearing index.

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