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Development Of A Subsidence Model For Cayirhan Coal MineHaciosmanoglu, Esenay Meryem 01 October 2004 (has links) (PDF)
In this study, subsidence analyses were carried out for panels B14, B12, B10, B02, C12, C10, C08 of Ç / ayirhan Lignite Mine using in-situ subsidence measurements.
Using the measurements from stations, installed both parallel and perpendicular to panel-advance direction, subsidence profiles were plotted as a function of time and distance from panel center. Horizontal displacement and strain curves were also plotted and compared with subsidence profiles.
There are various methods used for subsidence prediction. In this study however, a subsidence model was developed based on empirical model obtained from nonlinear regression analysis. During the analyses SPSS (V.10.0) software was used and the unknown parameters associated with subsidence function were determined for the stations above B14 panel. Since it was too complicated to take all the affecting factors into consideration, only the parameters which could be estimated by statistical evaluation were taken into account during analyses.
One significant contribution of this study to subsidence subject was the comparison of the subsidence values measured during this investigation with the values predicted by some other empirical methods.
In this study, the structural damages to the pylons installed on ground surface above retreating longwall panels were also investigated by the use of previous studies. Slope as well as horizontal strain changes caused by ground movements
due to underground mining were determined.
Last but not least, it should be stated another significant contribution of this study to engineering was the collection of a significant database obtained from field measurements.
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Soil Erosion Risk Mapping Using Geographic Information Systems: A Case Study On Kocadere Creek Watershed, IzmirOkalp, Kivanc 01 December 2005 (has links) (PDF)
Soil erosion is a major global environmental problem that is increasing year by year in Turkey. Preventing soil erosion requires political, economic and technical actions / before these actions we must learn properties and behaviors of our soil resources. The aims of this study are to estimate annual soil loss rates of a watershed with integrated models within GIS framework and to map the soil erosion risk for a complex terrain. In this study, annual soil loss rates are estimated using the Universal Soil Loss Equation (USLE) that has been used for five decades all over the world. The main problem in estimating the soil loss rate is determining suitable slope length parameters of USLE for complex terrains in grid based approaches. Different algorithms are evaluated for calculating slope length parameters of the study area namely Kocadere Creek Watershed, which can be considered as a complex terrain. Hickey& / #8217 / s algorithm gives more reliable topographic factor values than Mitasova& / #8217 / s and Moore& / #8217 / s. Satellite image driven cover and management parameter (C) determination is performed by scaling NDVI values to approximate C values by using European Soil Bureau& / #8217 / s formula. After the estimation of annual soil loss rates, watershed is mapped into three different erosion risk classes (low, moderate, high) by using two different classification approaches: boolean and fuzzy classifications. Fuzzy classifications are based on (I) only topographic factor and, (II) both topographic and C factors of USLE. By comparing three different classified risk maps, it is found that! in the study area topography dominates erosion process on bare soils and areas having sparse vegetation.
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Measurement of branching fractions and form factor parameters of B->Dlnu and B->D*lnu decays at BaBarHamano, Kenji 16 October 2008 (has links)
We use a global fit to determine the form factor slopes and branching fractions of the decays B --> Dlnu and B --> D*lnu. We reconstruct Dl pairs and construct a 3-dimensional distribution binned in lepton momentum, D momentum and cosTheta(B-Dl). These kinematic variables provide good separation between the signal and background. We fit electron and muon samples separately and combine them after calculating systematic uncertainties. The form factor slopes, rhoD^2 for B --> Dlnu and rho^2 for B --> D*lnu decays, are measured to be rhoD^2 = 1.22 +- 0.04 +- 0.07 and rho^2 = 1.21 +- 0.02 +- 0.07, where the errors are statistical and systematic, respectively. Branching fractions are fitted to be B(B+ --> D0lnu) = (2.36 +- 0.03 +- 0.12) % and B(B^+ --> D*0lnu) = (5.37 +- 0.02 +- 0.21) %. We use these results to determine the products, G(1)|Vcb| = (43.8 +- 0.8 +- 2.3)*10^{-3} and F(1)|Vcb| = (35.7 +- 0.2 +- 1.2)*10^{-3} of the form factors at zero recoil and the CKM matrix element |Vcb|, from which |Vcb| can be extracted using theoretical input.
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Jämförelse av metod vid stabilitetsanalys i bergslänter / Comparison of Methods for Slope Stability AnalysisEkberg Bergman, Emelie January 2018 (has links)
En bergslänts stabilitet styrs av berggrundens egenskaper, så som sprickegenskaper och bergkvalité. För att uppnå önskad stabilitet i en bergslänt behöver de bergmekaniska parametrarna kartläggas och analyseras för att fastställa risker och stabilitetsåtgärder. Syftet med studien är att utvärdera kvalitén på bergteknisk data från digitalfotogrammetriska 3D-modeller genom att jämföra resultatet med manuella mätningar från konventionell kartläggning. Målet är även att utforska potentialen för användning av fotogrammetrisk 3D-modellering vid stabilitetsanalyser i bergslänter genom att utvärdera den bergtekniska analys som kan göras utifrån fotogrammetrisk data. Sprickmätningar framtagna från 3D-modellen visade sig ha samma kvalité som manuella mätningar tagna enligt konventionell metod. Den UAS-baserade fotogrammetrin kan dock inte ersätta den konventionella analysen helt vid stabilitetsanalyser men kan användas som ett kompletterande verktyg i bergtekniska undersökningar. Fotogrammetrin möjliggör datainsamling från ett säkrare avstånd vilket minskar riskmomenten som den konventionella metoden medför vid arbete i fält. Den digitala metoden visade sig även ha fler fördelar såsom möjligheten av kartläggning och analysering framför datorn för mindre tids- och kostnadskrävande moment, digital datalagring samt att slänter med begränsad åtkomst kan karteras. / The stability of a rock slope is controlled by the rock’s mechanical properties, such as rock quality and facets. To achieve the desired stability in a rock slope, the mechanical parameters need to be mapped and analysed to determine possible failures and decide necessary stability measures. The purpose of this study is to evaluate the quality of rock technical data from digital photogrammetry 3D models by comparing the result with manual measurements from conventional mapping. The goal is also to explore the potential uses of photogrammetric 3D models for rock slope stability analyses by evaluate the photogrammetric data. Facets extracted from 3D models were found to have the same quality as manual measurements. However, the UAS-based method cannot completely replace the conventional method but can be useful as a complementary tool. Photogrammetry enables the collection of data from a safer distance, which reduces workplace hazards that the conventional method entails. The digital method also proved to have more advantages, such as the possibility of digital mapping and analysing which is less costly and time-consuming, digital data storage and the possibility to access outcrops that can’t be mapped with manually measurements due to inaccessibility.
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Etude de nano-transistors à faible pente sous le seuil pour des applications très basse consommation / Steep slope nano-transistors for ultra low power applicationsVillalon, Anthony 10 December 2014 (has links)
Le transistor à effet tunnel bande à bande (TFET) est une architecture PIN à grille capable d’obtenir une pente sous le seuil inférieure à 60mV/dec à température ambiante, ce qui représente un avantage par rapport au MOSFET dans le cas d’applications basse consommation. L’objectif de cette thèse est d’étudier et de caractériser des TFETs fabriqués au CEA-LETI (sur substrats SOI avec les procédés standards CMOS), afin de comprendre et d’optimiser ces dispositifs. La première génération de TFETs a été réalisée en architecture planaire (FDSOI) et fournit une étude sur l’impact de l’hétérojonction canal source, de l’épaisseur du canal et de la température de recuit sur les performances. La seconde génération a été réalisée en architecture nanofil SiGe planaire, dont l’impact de la géométrie a été étudié en détail. Les mesures ont permis de valider l’injection par effet tunnel bande à bande, et les performances observées ont été comparées à la littérature et aux MOSFET. Par ailleurs, des caractérisations avancées ont également mené à une meilleure compréhension des caractéristiques de sortie courant-tension. Finalement, des mesures basse température nous avons confirmé la présence de défauts proches des jonctions (à l’origine des limitations de pente sous le seuil) et ainsi proposé des voies d’optimisation pour s’en affranchir. / Band to band tunneling field effect transistor (TFET) is a PIN-gated architecture able to reach sub 60mV/dec subthreshold slopes at room temperature, which is an advantage over MOSFET in low power applications. The objective of this thesis is to study and characterize TFETs fabricated in CEA-LETI using MOSFET SOI technology. The first generation of devices is realized on planar FDSOI technology, and studies the impact of source/channel heterojunction, channel thickness and annealing temperature on device performances. The second generation is planar SiGe nanowire architecture, with research focusing on the impact of the wire geometry. Through measurements we were able to prove the band to band tunneling injection, while the reported performances were compared with literature and with MOSFET. Furthermore, advanced characterizations led to a better understanding of the output characteristics. Through low temperature measurements we confirmed existence of defects close to the junctions (which cause slope degradation), as well as on which process steps to improve in the future.
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Development of an acoustic emission waveguide-based system for monitoring of rock slope deformation mechanismsCodeglia, Daniela January 2017 (has links)
Hundreds of thousands of landslides occur every year around the world impacting on people's lives. Monitoring techniques able to foresee imminent collapse and provide a warning in time useful for action to be taken are essential for risk reduction and disaster prevention. Acoustic emission (AE) is generated in soil and rock materials by rearrangement of particles during displacement or increasing damage in the microstructure preceding a collapse; therefore AE is appropriate for estimation of slope deformation. To overcome the high attenuation that characterise geological materials and thus to be able to monitor AE activity, a system called Slope ALARMS that makes use of a waveguide to transmit AE waves from a deforming zone to a piezoelectric transducer was developed. The system quantifies acoustic activity as Ring Down Count (RDC) rates. In soil applications RDC rates have been correlated with the rate of deformation, however, the application to rock slopes poses new challenges over the significance of the measured AE trends, requiring new interpretation strategies. In order to develop new approaches to interpret acoustic emission rates measured within rock slopes, the system was installed at two trial sites in Italy and Austria. RDC rates from these sites, which have been measured over 6 and 2.5 years respectively, are analysed and clear and recurring trends were identified. The comparison of AE trends with response from a series of traditional instruments available at the sites allowed correlation with changes in external slope loading and internal stress changes. AE signatures from the limestone slope at the Italian site have been identified as generated in response to variations in the groundwater level and snow loading. At the conglomerate slope in Austria, AE signatures include the detachment of small boulders from the slope surface caused by the succession of freeze-thaw cycles during winter time. Consideration was also given to laboratory testing of specific system elements and field experiments. A framework towards strategies to interpret measured acoustic emission trends is provided for the use of the system within rock slopes.
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[en] DEVELOPMENT OF A TRANSIENT MATHEMATICAL MODEL FOR THE PREDICTION OF PLANAR LANDSLIDES IN NATURAL SLOPES / [pt] DESENVOLVIMENTO DE UM MODELO MATEMÁTICO TRANSIENTE PARA PREVISÃO DE ESCORREGAMENTOS PLANARES EM ENCOSTASALEXANDRE CONTI 04 September 2018 (has links)
[pt] Esse trabalho tem como objetivo desenvolver um modelo determinístico transiente de previsão de escorregamentos planares em encostas, para escalas em nível de bacia hidrográfica (1:2000 a 1:5000). No modelo são aplicadas as teorias de Green-Ampt (1934) e de O Loughlin (1986), essa última utilizada no programa SHALSTAB (MONTGOMERY e DIETRICH, 1994), além da teoria talude infinito 2D e 3D. Também são considerados nas análises a não saturação do solo e os efeitos da vegetação. O evento estudado para aplicação e teste do modelo refere-se ao ocorrido em 1996, nas bacias do Quitite e Papagaio em Jacarepaguá, Zona Oeste do Rio de Janeiro. Além do mapeamento do fator de segurança nas bacias, também são gerados mapas com o escoamento superficial acumulado, e tenta-se correlacionar ambos com as cicatrizes que ocorreram no caso de estudo. / [en] The aim of this work is to develop a physically-based transient model for the prediction of planar landslides in natural slopes. The application scale of the model is for a hydrographic basin (1:2000 to 1:5000). The theories of Green-Ampt (1934) and O Loughlin (1986), the second one used in the SHALSTAB program (MONTGOMERY e DIETRICH, 1994), and the infinite slope 2D and 3D are used in the model. The effect of the unsaturation and the vegetation is also considered in the analysis. The case study for the test of the model is the 1996 event that took place in the Quitite and Papagaio basins, in Jacarepaguá, Zona Oeste of Rio de Janeiro. Besides mapping the safety factor in the basins, maps of the accumulated runoff were also generated. This work also tries to correlate the runoff as another factor that caused the landslides.
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Etude de l'écoulement à forte pente autour d'un cylindre émergent / Study of the high slope flow around a piercing cylinderDucrocq, Thomas 19 October 2016 (has links)
Les barrages sur les rivières sont des obstacles à la migration piscicole. Les passes à poissons sont des ouvrages permettant aux espèces piscicoles de migrer, autorisant le rétablissement de la continuité écologique des cours d'eau. Le but de ce travail est de mieux comprendre les phénomènes physiques présents dans les passes à poissons naturelles. Ces passes sont des canaux à forte pente, équipé de rangées de plots en quinconce. Pour valider la pertinence de l'utilisation d'un modèle numérique, l'étude s'est limitée à l'écoulement autour d'un cylindre émergent placé au centre d'un canal. Le travail est décomposé en deux parties, une expérimentale et une numérique. La partie expérimentale est conduite dans un canal transparent de 4m de long, 0,4m de large et 0,4m de hauteur. Le diamètre du cylindre est 4cm et sa hauteur 20cm (toujours émergent). Les cas étudiés sont des débits de 5, 10, 15 et 20 l/s pour une pente nulle. Les nombres de Froude sont supérieurs à 0,5 et les nombres de Reynolds, basés sur le diamètre, sont compris entre 15000 et 50000. Les écoulements ont été filmés et un algorithme de suivi de particules (PTV) a été développé. Des zones de faibles vitesses existent, même pour Fr=1, pouvant assurer des zones de refuge pour le poisson. Les forces de trainée ont été mesurées sur le plot. Les évolutions des coefficients de trainée avec le nombre de Froude et des rapports de forme de l'écoulement autour du plot ont ainsi été évaluées. La partie numérique est réalisée avec OpenFOAM pour 4 cas d'étude (Q=10 et 20 l/s, S=0 et 2%) et 2 modèles de turbulence URANS, le RNG k-epsilon et le k-omega SST. Des modélisations en 2D ont également été faites avec Telemac 2D. Les résultats obtenus ont été comparés aux résultats expérimentaux. La modélisation 2D (shallow water) est exploitable seulement pour des nombres de Froude faibles, d'où la nécessité des modélisations en 3D. Le modèle komega SST semble le mieux adapté pour reproduire les écoulements étudiés. Les vitesses locales et les structures en 3D, non quantifiables expérimentalement, ont ensuite été décrites. Les influences du fond et de la surface libre sur le sillage apparaissent clairement en provoquant des vitesses verticales et des tourbillons à grandes échelles. Enfin, une simulation en LES a été conduite. Les structures tourbillonnaires sont mieux représentées que pour les modèles URANS, mais les temps de calcul sont grands. / The dams on rivers are fishes migration obstacles. The fishways are devices allowing the fishes to migrate, permitting the restauration of the ecological continuity. The aim of this work is to better comprehend the physical phenomena existing in the nature-like fishways. This kind of fishway is a high slope channel with staggered rows of blocks. To validate the relevance of the use of a numerical model, the study is limited to the flow around a single free surface piercing cylinder placed in the center of a flume. The work is in two parts, experimental and numérical. The experimental part is conducted in a transparent flume of 4m length, 0.4m width and 0.4m height. The cylinder diameter is 4cm and its height 20cm (always emerged). The studied cases are flow rates of 5 to 20 l/s for a flat bed. The Froude numbers are over 0.5 et the Reynolds numbers, based on the diameter, are in between 15000 and 50000. The flows were filmed and a particules tracking velocimetry (PTV) algorithm was developped. Slow velocities areas exist, even for Fr=1, allowing shelter zones for a fish. The drag forces were also measured. The drag coefficients evolutions with the Froude number and with the flow aspect ratio were estimated. The numerical part is done with OpenFOAM for 4 cases (Q=10 et 20 l/s, S=0 et 2%) and 2 URANS turbulence models, RNG k-epsilon and k-omega SST. 2D simulations are also carried out with Telemac2D. The results are compared with the experimental ones. The 2D modelisation (shallow water) is workable only for small Froude numbers, which justifies the 3D modelisation. The k-omega SST seems the most relevant to reproduce the studied flows. The local velocities and 3D structures, unquantifiable experimentally, were described. The bed and free surface influences on the wake are clearly shown leading to vertical velocities and big scale vorticies. Finally, a LES simulation was conducted. The vortex structures are better reproducted than the URANS simulations, but the computation times are significant.
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Impacto da recuperação de área degradada sobre as respostas hidrológicas e sedimentológicas em ambiente semiárido / Impact of the recovery of a degraded area on the hydrological and sedimentary responses in semi-arid environmentAlmeida, Cícero Lima de January 2011 (has links)
ALMEIDA, Cícero Lima de. Impacto da recuperação de área degradada sobre as respostas hidrológicas e sedimentológicas em ambiente semiárido. 2011. 132 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2011. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-06-17T13:36:15Z
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Previous issue date: 2011 / As regiões semiáridas compreendem áreas muito sensíveis às alterações do seu ambiente natural. O semiárido brasileiro, por ser um dos mais populosos do mundo, está mais susceptível às atividades antrópicas, como o desmatamento para atividades agrosilvopastoris. Esta pesquisa foi desenvolvida no âmbito do projeto “Estudos dos processos de degradação/desertificação e suas relações com o uso da terra em sistemas de produção no semiárido cearense: o caso da microrregião de Sobral – Ceará”. A área experimental localiza-se no município de Irauçuba, inserida em um dos núcleos de desertificação do semiárido brasileiro. O clima da região é do tipo quente e semiárido com chuvas de verão (média anual de 530 mm) e índice de aridez 0,34. O solo é do tipo Planossolo Nátrico Órtico típico, A fraco; e a vegetação nativa é do tipo Caatinga arbustiva aberta. A principal atividade econômica da região é a pecuária extensiva (bovino e ovino) em sobrepastejo, sem uso de práticas conservacionistas. O presente trabalho tem como objetivo comparar os processos hidrossedimentológicos de duas encostas em ambiente semiárido: uma (370 m²) está submetida à prática de pousio desde 2000; enquanto que a outra (468 m²) se encontra degradada, sendo usada como área de pastagem há mais de vinte anos. As duas encostas possuem as mesmas condições de solo, clima e relevo, diferenciando-se somente quanto ao uso e à cobertura do solo. São comparadas analiticamente variáveis hidrológicas e sedimentológicas. Os experimentos foram realizados entre 01 de janeiro de 2010 e 15 de abril de 2011. Para promover essa comparação foram coletados dados de precipitação (lâmina e intensidade), escoamento superficial e perda de solo. A precipitação foi de 264 mm em 2010 e de 445 mm até 15 de abril de 2011, tendo sido registrados 55 eventos nos 16 meses. As chuvas de Irauçuba demonstraram alta variabilidade espacial: há diferença estatística (nível de significância de 5%) entre os dois pluviômetros usados na pesquisa, embora estejam a uma distância de apenas 200 m. O padrão hidrológico das chuvas na região é de intermediário a atrasado (70% dos eventos), o que causa maior potencial erosivo. Conclui-se, a partir da análise comparativa, que os dez anos de pousio reduziram em 60% o escoamento superficial em relação à encosta degradada. A menor precipitação capaz de gerar escoamento superficial foi 7,2 mm na encosta degradada, enquanto que esse valor foi de 8,6 mm para a encosta em pousio. Isso demonstra o incremento de abstração inicial da encosta preservada, ou seja, sua maior capacidade de retenção de umidade. O incremento da capacidade de retenção se dá através da interceptação vegetal, da serrapilheira e da camada superficial do solo. No entanto, observou-se que a maior precipitação incapaz de gerar escoamento superficial foi idêntica (17 mm) nas duas encostas. A explicação para tal resultado é que o parâmetro dominante nesse processo é a estrutura do solo: embora haja diferenças na superfície dos solos, os dez anos de pousio ainda não foram capazes de alterar sua estrutura, conforme avaliou Sousa em pesquisa independente. Observou-se que a taxa de decaimento da vazão foi sensivelmente afetada pela prática de pousio: a taxa, de 0,107 min-1 na encosta degrada, decresceu para 0,045 min-1 na encosta preservada. A menor taxa de decaimento de vazão na encosta em pousio indica o início da recuperação de seu escoamento de base, o que favorece maior permanência da água no corpo hídrico. Os dez anos de pousio também foram capazes de reduzir a perda de solo. Essa redução, de 83% em relação à encosta degradada, induz à melhoria das condições físicas, químicas e biológicas do solo, responsáveis pelo incremento da produção vegetal. Conclui-se, com base nos experimentos aqui realizados, que os dez anos de pousio melhoraram, de modo mensurável, as condições hidrológicas e sedimentológicas na encosta semiárida. A prática de pousio, portanto, pode ser adotada para fins de recuperação de áreas de Caatinga degradada. Sugere-se que sejam realizadas novas investigações, que avaliem a associação dessa prática a outras, a fim de intensificar o processo de recuperação de áreas degradadas no semiárido
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Estudo dos solos de uma encosta instável em São José - SC : intemperismo e comportamento geotécnico / Study of soils of an unstable slope in São José – SC : weathering and geotechnical behaviorHeidemann, Marcelo January 2015 (has links)
Uma encosta localizada no município de São José - SC apresenta extenso histórico de instabilidades. Do ponto de vista litológico há predominância de granitoides na área de estudos e a mesma é transpassada por uma falha preenchida por riolito bastante alterado devido à atividade hidrotermal. O intemperismo da rocha granítica deu origem a um perfil de alteração com espessura bastante variável e a solos com características geotécnicas, químicas e mineralógicas distintas, levando à discretização de cinco solos. Quatro solos residuais foram denominados solos residuais de granito amarelo (GrAm), vermelho (GrVm), com biotita (GrBt) e lateritizado (GrLt), e uma argila de preenchimento de descontinuidades (ArBr). Foi realizada uma série de análises químicas, empregadas na quantificação de índices de intemperismo. O avanço do processo de intemperismo tornou os solos residuais mais finos e plásticos e nas áreas em que a alteração hidrotermal foi mais intensa houve a transformação de feldspatos em biotitas. As curvas de retenção solo-água obtidas para os solos saprolíticos são unimodais, mas no caso do solo GrLt os dados experimentais ajustam-se a curvas bimodais. O processo de remoldagem dos solos impacta nos níveis de sucção desenvolvidos. Os ensaios de condutividade hidráulica mostraram que esta propriedade não depende unicamente da porosidade e nível de confinamento, sendo relevante a influência da estrutura e mineralogia. Os solos saprolíticos tem comportamento distinto do apresentado pelo solo GrLt, no qual ocorre brusca redução de ksat com aumento do confinamento. Ensaios de compressão confinada em amostras indeformadas, remoldadas e reconstituídas possibilitaram identificar a manifestação da estrutura e sua influência na deformabilidade dos solos. Constatou-se que esta suplanta a influência da porosidade. Não é possível definir uma única linha de compressão normal que descreva o comportamento de cada material independentemente da forma com que foram preparados os corpos de prova. Nos ensaios triaxiais a estrutura dos materiais atua de forma distinta daquela observada nos ensaios oedométricos, indicando que sua influência depende da trajetória de tensões. A mineralogia parece ter influência na resistência ao cisalhamento destes solos. O solo GrBt apresentou o mais baixo ângulo de atrito, da ordem de 26º. O solo GrVm tem ângulo de atrito de 32º, sendo o maior aqui obtido. Quando remoldados os solos respeitam linhas de estado crítico (CSL) bastante bem definidas, por conta da redução da influência da estrutura nos resultados. Quando indeformados também é possível o ajuste de CSL, mas a dispersão dos dados é maior. O comportamento dos solos não é normalizável, mesmo quando remoldado. Em ensaios ring shear foram medidos ângulos de atrito residual entre 22º (GrAm) e 13,8º (GrLt) nos solos residuais. No solo ArBr o baixo ângulo de atrito residual (8º) se deve à granulometria fina e composição rica em argilominerais e micas. Sua associação ao solo GrBt corrobora a concentração das rupturas de encosta na área de ocorrência destes materiais. As curvas tensão-deformação dos ensaios triaxiais puderam ser satisfatoriamente reproduzidas pelo modelo hardening, o qual foi empregado para representar o comportamento dos solos em análises de estabilidade por meio de elementos finitos. Tais análises foram confirmadas por análises por equilíbrio limite no que tange a definição de áreas mais suscetíveis a rupturas. / A hillside in the municipality of São José - SC has an extensive history of instabilities. Under a lithological point of view, there is a predominance of granitoids in the study area, which is crossed by a fault filled by an altered rhyolite, due to hydrothermal activity. The weathering of the granite rock gave rise to a soil profile with highly variable thickness and soils with distinct geotechnical, chemical and mineralogical properties, leading to the discretization of five soils. They were denominated as four granite residual soils, yellow (GrAm), red (GrVm), with biotite (GrBt) and lateritizated (GrLt), and a clay soil that filled discontinuities (ArBr). A series of chemical analysis was carried out and employed to quantify some weathering indexes. As the weathering processes increased the residual soils became finer and more plastic. In areas where hydrothermal alteration was more intense feldspar was transformed in biotite. Soil suction characteristic curves obtained for the saprolitic soils were unimodal, but in the case of GrLt soil bimodal curves fitted better to experimental data. Remolding of the soils impacted the suction levels developed. Hydraulic conductivity tests have shown that this property does not depend solely on the porosity and confining pressures but the influence of soil structure and mineralogy is relevant. The saprolitic soils show a different behavior as compared to GrLt, which suffers abrupt reduction of ksat when the confinement is increased. Oedometric tests on undisturbed, remolded and reconstituted specimens allowed the identification of the influence of structure on the soil deformability. It was found that this influence is larger than that of porosity. It was not possible to define a unique normal compression line to describe the behavior of each material, regardless of the specimens preparation. In triaxial tests, soil structure acts in a different way from the observed in oedometric tests, indicating that their influence depends on the stress path. The mineralogy appears to have influence on the shear strength of these soils. The soil GrBt has the lowest friction angle, around 26°, and soil GrVm has a friction angle of 32° the largest obtained. When remolded these soils obey critical state lines which are well defined due to the reduction of soil structure influence. Although was possible to define CSL for the undisturbed soil the data dispersion was bigger. These soils do not have normalizable behavior even when remolded. Residual friction angles of residual soils measured through ring shear tests ranged between 22° (GrAm) and 13,8º (GrLt). The soil ArBr showed a very low residual friction angle (8°) due to its fine grain size and its mineralogical composition rich in clay minerals and mica. The association of ArBr soil to the GrBt soil supports the concentration of slope failures in the area of occurrence of these materials. Stress-strain curves of triaxial tests were satisfactorily reproduced by the hardening model, which was employed to represent the soils behavior in stability analyzes using finite element method. Such results were validated by limit equilibrium analysis that were employed to define the areas more susceptible to failures.
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