<p>Trafiksystemet i Linköpings tätort bygger på två ringar, Y-ringen (yttre) och C- ringen (centrum), vilkas syfte är att avlasta stadens olika centrala delar. Den signalreglerade korsningen Industrigatan-Östgötagatan är en del av den så kallade Y-ringen och under vissa tider på dygnet finns det risk för köbildning. Antalet inkommande fordon i korsningen uppgick år 1999 till ca 28 000 per dygn och idag uppgår antalet till någonstansmellan 30 400-32 400 fordon/dygn. </p><p>Kommunen har planer på att på att etablera ett bostadsområde i Övre Vasastaden, vilket kan komma att påverka trafikmängderna i den studerade korsningen. En garanterad orsak till ökade trafikmängder är det faktum att Linköping ständigt ökar i invånarantal, med ökad folkmängd ökar även trafiken. Storleken på trafikökningen finns prognostiserad i olika trafikprognoser och dessa visar att när staden har 150 000 respektive 180 000 invånare kommer det inkommande flödet i aktuell korsning uppgå till ca 35 000 respektive ca 40 000 fordon/dygn. Framtida kö- och framkomlighetsproblem är därmed en realitet. </p><p>Med stöd av effektberäkningsprogrammet Capcal presenteras tre olika förslag på åtgärder där framkomlighetsproblemen undviks. Alternativ 1 innebär modifiering av trafiksignalerna och en förbjuden vänstersväng, alternativ 2 är en rund cirkulationsplats och alternativ 3 motsvaras av en oval cirkulationsplats. I de två sistnämnda alternativen föreslås även fyra alternativa lösningar för gång- och cykeltrafik. </p><p>En jämförelse mellan de olika alternativen visar att de ”bästa” effektmåtten erhålls vid alternativ 3 även om resultaten i alternativ 2 nästan är lika ”bra”. Däremot om kommunens prognoser skulle slå fel med 10 %, dvs om trafiken skulle öka med 10 % mer än beräknat, skulle endast alternativ 1 visa på godkända värden. Resonemanget kring rekommendationer av alternativ har delvis gjorts utifrån de framräknade effektmåtten men även med tanke på trafiksäkerheten för både de oskyddade trafikanterna och fordonstrafikanterna.</p>

Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.

Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.

Trafiksystemet i Linköpings tätort bygger på två ringar, Y-ringen (yttre) och C- ringen (centrum), vilkas syfte är att avlasta stadens olika centrala delar. Den signalreglerade korsningen Industrigatan-Östgötagatan är en del av den så kallade Y-ringen och under vissa tider på dygnet finns det risk för köbildning. Antalet inkommande fordon i korsningen uppgick år 1999 till ca 28 000 per dygn och idag uppgår antalet till någonstansmellan 30 400-32 400 fordon/dygn. Kommunen har planer på att på att etablera ett bostadsområde i Övre Vasastaden, vilket kan komma att påverka trafikmängderna i den studerade korsningen. En garanterad orsak till ökade trafikmängder är det faktum att Linköping ständigt ökar i invånarantal, med ökad folkmängd ökar även trafiken. Storleken på trafikökningen finns prognostiserad i olika trafikprognoser och dessa visar att när staden har 150 000 respektive 180 000 invånare kommer det inkommande flödet i aktuell korsning uppgå till ca 35 000 respektive ca 40 000 fordon/dygn. Framtida kö- och framkomlighetsproblem är därmed en realitet. Med stöd av effektberäkningsprogrammet Capcal presenteras tre olika förslag på åtgärder där framkomlighetsproblemen undviks. Alternativ 1 innebär modifiering av trafiksignalerna och en förbjuden vänstersväng, alternativ 2 är en rund cirkulationsplats och alternativ 3 motsvaras av en oval cirkulationsplats. I de två sistnämnda alternativen föreslås även fyra alternativa lösningar för gång- och cykeltrafik. En jämförelse mellan de olika alternativen visar att de ”bästa” effektmåtten erhålls vid alternativ 3 även om resultaten i alternativ 2 nästan är lika ”bra”. Däremot om kommunens prognoser skulle slå fel med 10 %, dvs om trafiken skulle öka med 10 % mer än beräknat, skulle endast alternativ 1 visa på godkända värden. Resonemanget kring rekommendationer av alternativ har delvis gjorts utifrån de framräknade effektmåtten men även med tanke på trafiksäkerheten för både de oskyddade trafikanterna och fordonstrafikanterna.

Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.

Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.

The subject of my thesis was traffic-engineering solution to the crossroads of the streets Osvobození - Podřevnická in several options. For these options were designed needed construction adjustment next was selected one option and after taht was carried out capacity assessment of the crossroads in accordance with relevant technical regulations. To verify the capacity assessment was carried out simulations using the proposed variants Aimsun.

No description available.

Nous reportons dans ce travail le comportement mécanique, dans le régime solide et en écoulement, de matériaux granulaires liés par un liquide non saturant, qui intervient par sa viscosité et par des effets capillaires. De tels matériaux, intermédiaires entre les assemblages granulaires secs et les suspensions très concentrées, sont étudiés expérimentalement et par simulations discrètes depuis la microstructure jusqu'au comportement macroscopique. Ainsi, on adopte une démarche multi-échelle, dont l’objectif est d’établir les fondements de la compréhension des phénomènes capillaires et/ou visqueux, qui interviennent dans la formulation de lois de comportement, et d'y intégrer une caractérisation de la microstructure de ces matériaux. Nous nous intéressons notamment au modèle d'interactions capillaire et visqueuse par ponts simples, dans un cadre où l'on fait varier l'inertie, le degré de confinement, le degré de friction du matériau ainsi que la quantité de liquide introduite. Pour répondre à cet objectif, ce travail de thèse s’articule autour des trois volets suivants :- Un travail de rhéologie expérimentale macroscopique sur matériau modèle (billes de polystyrènes monodisperses, mouillées avec une huile de silicone newtonienne) qui nous permet de délimiter des régimes d'écoulement et de caractériser l'influence de l'effet cohésif. Le format expérimental adopté nous permet de cisailler les échantillons sur des temps très longs et d'atteindre des régimes d'écoulement stationnaires. Ainsi, à l'instar des matériaux secs, on retrouve des régimes quasistatiques puis inertiels à mesure que la vitesse d'écoulement augmente. On met aussi en avant une très forte influence de l'effet cohésif qui tend à augmenter drastiquement la résistance au cisaillement et à diminuer la compacité de nos échantillons.- Des expériences de microtomographie à rayons X qui permettent d'étudier la microstructure à l'état statique. On remarque notamment une bonne homogénéité des échantillons, qu'ils soient faiblement ou fortement saturés. On détecte aussi un nombre non-négligeable de morphologies capillaires complexes, ce qui, par comparaison aux résultats de rhéologie macroscopique, ne semble pas influencer les propriétés d'écoulement. Ce résultat est particulièrement intéressant puisqu’il montre la capacité du modèle d’interactions par pont simple à décrire le comportement de systèmes à priori hors de sa portée descriptive.- Des simulations numériques discrètes qui nous permettent d'élargir fortement la gamme de paramètres étudiés, notamment avec des caractéristiques du matériau comme la friction de Coulomb. L'étude micromécanique, permise par les simulations, autorise aussi l'analyse des questions d'anisotropie, de coordination et de contraintes capillaires. On met en avant l'importance des interactions capillaires à distance lors de l'utilisation d'un modèle de contraintes effectives. Les limites de ce modèle, usuellement adapté à la description du comportement en régime quasi-statique, sont aussi testées et discutées dans le régime inertiel. La bonne concordance entre résultats expérimentaux et numériques nous aura permis de valider et calibrer un modèle numérique qui, en retour, aura donc fourni une analyse viable des effets microstructurels pour la compréhension du comportement et la transition de l'échelle microscopique à l'échelle macroscopique / With this doctoral research, we report on the solid and liquid-like mechanical behaviors of wet granular materials, which exhibit viscous and capillary effects. Such systems, standing between dry and immersed granular materials, are studied both in experiments and discrete numerical simulations, from the microstructural aspects to the mechanical behavior. We therefore adopt a multiscale approach whose purposes are to understand the origins and roles of capillary and viscous effects in constitutive laws and to include a microstructural description within these laws. We are interested in the simple bridge model for the illustration of viscous and capillary effects in the case of quasistatic and inertial flows, where the confining forces, the Coulomb friction and the liquid quantity can vary. To answer such questions, this thesis is articulated around the 3 following topics :- A study based on macroscopic rheological experiments with a simple model material (monodisperse polystyrene beads, wetted with a Newtonian silicon oil) which enables us to distinguish the flow regimes and to characterize the influence of cohesive effects. The experimental framework allows for long time shearing experiments, where the materials can reach their steady state behavior. Alike dry systems, wet granular materials still exhibit a quasistatic and an inertial regime with increasing flow velocity. We show the noticeable influence of capillary effects which strongly increases the shear resistance and reduces the materials density.- X-ray microtomographic experiments enabling the microstructural study of static samples. We witness a good homogeneity of our samples whether slightly or strongly saturated. A non-negligible number of very complex capillary bonds were detected, which stresses, when compared with macroscopic rheological results, their lack of influence on the flow properties. This result is very noticeable as it demonstrates the ability of the simple bridge model to illustrate the behavior of materials which would not be included a priori within its reach.- Discrete numerical simulations allowing us to strongly improve the range of the parameters of the study, especially in the case of material characteristics such as Coulomb friction. The micromechanical study emerging from simulations, allows us to analyze anisotropy, coordination and capillary stresses questions. We underline the great importance of long-range capillary interactions when using an effective stress model. The limits of such model, usually adopted to describe the behavior in the quasistatic regime, are also tested and debated in the inertial regime. The good agreement between numerical and experimental results enabled us to validate and calibrate a numerical model which, in return, offered a reliable analysis of microstructural effects for the understanding of the mechanical behavior and for the transition from the microscopic to the macroscopic scale

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The knowledge of soil damage due forest harvest is important for adequate management of soil physical conditions, to increase wood yield and decrease soil degradation. This study evaluates the influence of different operations of forest harvest on the soil physical properties of a typical Hapludalf and an abrupt Hapludalf. The research was realized in areas under 17 years old commercial forest of Pinus taeda. The soil physical properties were evaluated before and after the forest harvest. The treatments, constituted by the different operations of Pinus harvest were as following: before the harvest; after trees cut; after wood dragging with one pass of the skidder; after wood dragging with three passes of the skidder and after removing the wood from storing place (piles). Undisturbed soil samples were taken from layers of 0.00-0.05; 0.05-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.40m to determine bulk density, microporosity, macroporosity, total porosity, gravimetric soil moisture and saturated hydraulic conductivity. Soil resistance to penetration was evaluated either. To evaluate compressive behavior of soil, undisturbed soil samples were taken from layers of 0.025-0.05m and 0.10-0.125m to determine the bulk density before and after the uniaxial compression test; soil deformation after the test; gravimetric moisture and degree of saturation of soil before the test. The precompression stress and compression index were obtained from compression curves. The soil bulk density of the typic Hapludalf presented biggest reduction after three passes of the skidder, due the superposition of the tractor passes and its pressure during wood dragging. The soil resistance to penetration had the biggest values, indicating the biggest degradation due to the forest harvest. After three steps of the skidder the compaction took place with bigger intensity in the soil surface and that had a uniform distribution in the layers of the soil profile. Before the harvest, after the forest cut, after one step of the skidder and after the wood retreat from shipyard the compaction took place more in the vertical direction. Considering the larger deformations and compression index, the soil should be trafficked with degree of saturation of 65 to 69% to avoid larger deformations and reduce susceptibility of soil to compaction. In the abrupt Hapludalf the soil compaction was smaller. Such a fact was indicated by smaller soil resistance to the mechanical penetration, which indicates a less degree of compaction. The soil saturated hydraulic conductivity was the parameter that better expressed the compaction of the Alfisols. / O conhecimento dos procedimentos envolvidos na colheita florestal, bem como os danos provocados pelo sistema de colheita é importante para se realizar um manejo adequado no solo, melhorar a produção de madeira e reduzir a degradação do solo. O objetivo deste estudo foi avaliar a influência das diferentes operações da colheita florestal nas propriedades físicas de um Argissolo Vermelho Distrófico típico e um Argissolo Vermelho Distrófico abrúptico, considerando que o tráfego das máquinas, geralmente, resulta em impactos no ecossistema, de forma a influenciar a compactação do solo e a produtividade da floresta. A pesquisa foi realizada em áreas sob floresta comercial de Pinus taeda, com 17 anos de idade. Os tratamentos, constituídos pelas diferentes etapas da colheita florestal foram: antes da colheita florestal; após o corte das árvores; após o arraste com uma passada do skidder; após o arraste com três passadas do skidder e após a retirada da madeira do estaleiro. Amostras de solo com estrutura preservada foram coletadas nas camadas de 0,00-0,05; 0,05-0,10; 0,10-0,20; 0,20-0,30 e 0,30-0,40m para determinação da densidade, da microporosidade, da macroporosidade, da porosidade total, da umidade gravimétrica e da condutividade hidráulica do solo saturado. A resistência do solo à penetração foi avaliada até 0,50m de profundidade. No estudo do comportamento compressivo do solo, foram coletadas amostras com estrutura preservada nas camadas de 0,025-0,05m e de 0,10-0,125m, determinando-se a densidade do solo antes e ao final do teste de compressão uniaxial, a deformação ao final do teste, a umidade gravimétrica e grau de saturação antes do teste de compressão e a pressão de preconsolidação e índice de compressão. Os resultados obtidos indicam que no PVd típico, a densidade do solo apresentou maior redução após três passadas do skidder, fato relacionado à sobreposição das passadas e a pressão exercida pela máquina sobre o solo na atividade de arraste da madeira. O solo apresentou os maiores valores de resistência à penetração mecânica, indicando a maior degradação devido à colheita florestal. Após três passadas do skidder a compactação ocorreu com maior intensidade na superfície do solo e essa apresentou uma distribuição uniforme nas camadas do perfil. Antes da colheita, após o corte florestal, após uma passada do skidder e após a retirada da madeira do estaleiro a compactação ocorreu mais no sentido vertical. Considerando a deformação do solo e o índice de compressão, o solo deve ser trafegado com grau de saturação de 65 a 69%, para evitar maiores deformações e reduzir a suscetibilidade à compactação. No Argissolo Vermelho Distrófico abrúptico a compactação do solo ocorreu em menor intensidade. Tal fato foi comprovado pela menor resistência do solo à penetração mecânica, relacionada a uma menor compactação do solo. A condutividade hidráulica do solo foi o parâmetro que melhor expressou a compactação dos Argissolos.