No Brasil pouco se estuda sobre as estratégias de amostragem em áreas com mais de um tipo de solo e várias feições de paisagem, estratégias estas, importantes para mapear a variabilidade espacial dos atributos físicos: frações granulométricas, como também a correlação destas com os parâmetros geomorfológicos: altitude e inclinação máxima da área amostrada da extensão multivariada da krigagem, a cokrigagem. Essa extensão multivariada permite a associação de duas variáveis dependentes gerarem novas informações correlacionadas através do modelo de variância cruzada. O objetivo deste trabalho foi avaliar a correlação espacial entre a distribuição da fração granulométrica com os parâmetros de altitude e a inclinação máxima através de uma densidade amostral agregada (100x100 e 50x50m) com dois níveis de densidade amostral, 20x20 e 40x40m. O estudo se deu numa área de 180 ha, onde se coletou frações de solo numa grade amostral agregada, ou seja, um arranjo amostral 100x100m e três sub-grades de 50x50m distribuídas aleatoriamente na área. Foi realizada análise estatística descritiva dos dados processados no laboratório e a análise espacial através de modelos de variância. De posse dos modelos ajustados na análise dos variogramas, realizou a interpolação pela krigagem para as frações granulométricas e através dos variogramas cruzados pela cokrigagem, as correlações dessas frações com os dados, obtidos pelo modelo digital de elevação, da altitude e a inclinação máxima do terreno da área e comparada, através dos mapas, essas mesmas correlações em densidades amostrais diferentes. A partir dos modelos de mapas gerados, chegou aos seguintes resultados: houve uma moderada variabilidade das frações granulométricas e uma moderada dependência espacial. De acordo com os parâmetros da variância cruzada a distribuição espacial da fração areia correlacionada com a altitude e com a inclinação máxima não diferenciou significativamente em relação aos níveis de densidade amostral 20x20m e 40x40m, praticamente não houve correlação entre a fração areia e a altitude, pois não apresentou um padrão definido de distribuição espacial. Pode-se concluir que a declividade influenciou na distribuição dos atributos físicos do solo. Como também foi avaliada a disponibilidade hídrica na área do pivô da Fazenda, foi constatada a forte correlação do atributo argila+silte com a capacidade de água disponível (CAD), enfatizando a dependência da disponibilidade hídrica em relação aos atributos físicos do solo. / In Brazil, few studied are related about soil sampling strategies in areas with more than one type soil and various features of the landscape, these strategies are important to map the spatial variability of physical attributes: size fractions, as well as the correlation of these with geomorphologic parameters: altitude and maximum slope of the sampled area of the multivariate extension of kriging, cokriging. This extension allows multivariate combination of two dependent variables to generate new information correlated with the model cross variance. The objective of this study was to evaluate the spatial correlation between the distribution of particle size fraction with the parameters of altitude and terrain slope through a maximum aggregate sample density (100x100 and 50x50m) with two levels of sample density, 20x20 and 40x40m. The study was an area of 180 ha, where fractions of collected soil at a sampling grid aggregate, ie an arrangement 100x100m sample and three sub-grids 50x50m randomly distributed in the area. We performed a descriptive statistical analysis of data processed in the laboratory and spatial analysis through models of variance. In possession of the adjusted models in the analysis of variogram for kriging interpolation performed for the fractions and through the variogram crossed by cokriging, the correlations of these fractions with the data obtained by digital elevation model, altitude and the maximum slope of the land area and compared, through maps, these same correlations in different sampling densities. From the models generated maps, it was reached the following results: there was a moderate variability in size fractions and a moderate spatial dependence. In accordance with parameters of cross (semi)variance the spatial distribution of the sand fraction correlated with altitude and the maximum slope did not differ significantly from the levels of sample density 20x20m and 40x40m, virtually no correlation between the sand fraction and altitude because it did not show a definite pattern of spatial distribution. It can be concluded that the slope influenced the distribution of soil physical attributes studieds. It was also quantified the water availability in the area under the center pivot equipment, it was found a strong correlation of the attribute clay + silt with TAW (total available water), emphasizing the dependence on water availability in relation to soil physical properties.

Métodos de estudo de estabilidade de taludes são diversificados e estão bastante desenvolvidos e consolidados na Geologia de Engenharia. Paralelamente, a aplicação de ferramentas de geoprocessamento tem se intensificado bastante em todos os campos de conhecimento técnico científico, demonstrando ser uma ferramenta de grande importância e auxiliando a tomada de decisão, sendo inclusive utilizado no estudo de escorregamentos e processos correlatos a instabilização de taludes. Dentro deste contexto, este trabalho objetivou desenvolver uma abordagem de estudo para caracterizar a estabilidade de taludes de mineração combinando técnicas e métodos usuais de investigação e análise geológico-geotécnica. A pesquisa foi aplicada nas minas de ferro do complexo Fazendão, localizadas no município de Catas Altas (MG) e são de propriedade da companhia VALE S/A. O trabalho está dividido essencialmente em duas etapas de estudo: primeiramente um foco semi-regional, seguido de um estudo de detalhe em uma mina em particular. Para a análise semi-regional foi utilizando Sistema de Informação Geográfica - SIG para geração de mapas temáticos, abrangendo todas as minas do complexo. Já no estudo de detalhe, foram realizados levantamentos sistemáticos em campo na mina de São Luís, sendo posteriormente realizado um levantamento específico de seções dentro da mina. A partir dos mapas temáticos foram identificadas as principais drenagens e bacias hidrográficas da área de estudo. Estes mapas juntamente com os mapas de declividade, curvatura, direção de vertente e mapa geológico, forneceram informações importantes sobre a região onde as minas estão inseridas, o que possibilita um melhor planejamento das intervenções que vierem a serem feitas. As análises por estereogramas indicaram várias situações de instabilidade frente às direções de fraturas e bandamento, com relação à direção e ângulo de mergulho de alguns taludes, sendo várias destas feições identificadas em campo. Por outro lado, a análise por equilíbrio limite apontam fatores de segurança muito altos, desde que não ocorra a influência do nível de água. Por fim, a abordagem utilizada foi bastante útil na caracterização da região. O estudo semi-regional em conjunto com uma análise de detalhe permitiu identificar feições que comprometem a segurança dentro da mina. A partir do resultado deste estudo, espera-se auxiliar a programação do avanço da mina de forma otimizar sua exploração, sem comprometer a segurança. / Methods of study of slope stability are diverse and are well developed and consolidated in Engineering Geology. In addition, the application of GIS tools has intensified greatly in all fields of scientific expertise, proven to be an important tool aiding in the decision making, including being used in the study of landslides and processes related to slope instability. Within this context, this study aimed to develop a approach to characterize the stability of slopes mining combining geoprocessing techniques and the usual methods of investigation and analysis of geological-geotechnical. The research was applied to the iron mines of Fazendão complex, located in the municipality of Catas Altas (MG) and are the property of the company VALE S/A. The research is divided into two main stages of the study: first a semi-regional focus followed by a study in detail of a particular mine. For the semi-regional analysis has been using GIS for thematic maps, covering all the mines the complex. In the study of detail, systematic surveys were conducted in the field for geological and geotechnical parameters in the mine of São Luís, and later conducted a survey within specific sections of the mine. From the thematic maps were identified the major drainage and hydrographic basins of the study area. Those maps, analyzed together with the slope map, curvature, direction of slope and geologic map provided important information about the area which the mines are located, allowing better planning of interventions that were to be made. The stereograms analyzes indicated various situations of instability depending of the fractures and banding directions, according to direction and dip angle of some slopes, some of it identified in the field. Moreover, the limit equilibrium analysis safety factors showed very high, since there was no influence of the water levels. Finally, the used approach was useful in characterizing the region. The semi-regional study combined with a detail analysis allowed to identify features that compromise the safety inside the mine. From the results of this study is expected to help advance the schedule of the mine in order to optimize their operations, without compromising security.

Les missions océanographiques Carambar (2010), Carambar 1.5 (2014) et Carambar 2 (2016-2017) menées au large de la pente nord du Petit Banc des Bahamas (PBB) ont permis d’étudier les processus d’export sédimentaire quaternaires sur ce système carbonaté. Les 24 270 km² de données bathymétriques couplées aux 6398 km de lignes sismiques très haute-résolution et aux 42 carottes sédimentaires reparties entre – 177 m et – 4873 m de profondeur ont permis de caractériser ce système depuis la pente supérieure jusqu’à la plaine abyssale.Le travail présenté ici s’intéresse aux résultats obtenus sur les carottes sédimentaires prélevées sur le haut de pente supérieur du PBB (Carambar 1.5) et celles obtenues sur le bas de pente et dans la zone du canyon du Great connecté à la plaine abyssale (Carambar 2). Ils viennent compléter les résultats obtenus précédemment par Tournadour (2015) et Chabaud (2016) sur les pentes inférieures et moyennes.Un prisme de haut niveau marin se dépose haut de pente supérieure. Actuellement, ce prisme daté de l’holocène s’étend de - 177 m à – 360 m. Les dépôts sédimentaires sont principalement engendrés parle density cascading et le passage d’ouragans. Son alimentation La formation du prisme a débuté il y a13,6 ± 3,5 ka cal BP, après le Meltwater Pulse 1A. Les Meltwater Pulses ont engendré la formation de terrasses qui correspondent alors à des environnements peu profonds et qui induisent une production carbonatée qui peut être exportée vers le prisme. La principale phase de développement du prisme est datée à 6,5 ± 0,9 ka cal BP, quand le niveau marin a finalement atteint le rebord de plate-forme. La sédimentation du bas de pente suggère une alimentation principalement pélagique et liée aux passages des courants plutôt qu’aux apports de plate-forme. Les variations dans les faciès dans ces dépôts sont donc issues de variations climatiques (intensification des courants, apports arctiques). La sédimentation de cette zone semble similaire à celle retrouvé sur la Blake Outer Ridge à 400 km au nord.Entre -1300 et -4800 m, la pente se caractérise par le canyon géant du Great Abaco. L’alimentation peu fréquente de ce canyon contrôlé structuralement a lieu principalement par le biais de tributaires, la tête du canyon ne semble pas être le lieu préférentiel de passage de courants de turbidité fréquents. / Over the past decade, the Little Bahamas Bank (LBB) in the Caribbean has been at the heart of oceanographic cruises Carambar (2010), Caramba 1.5 (2014) and Carambar 2 (2016-2017). These scientific expeditions were carried out with the aim of improving our knowledge of the processes tha controlled sediment export during the Quaternary in this tropical setting. Thus, bathymetric datacovering some 24,270 km² of seabed, high-resolution seismic lines running over 6,398 km and 42sediment cores ranging from 177 to 4,873 m water depth were collected in the upper slope through tothe abyssal plane of the LBB system.This study focusses on those sediment cores retrieved in the upper (Carambar 1.5) and lower slope ofthe LBB and those from the Great Canyon (Carambar 2) which is connected to the abyssal plane. These results are complementary to previous studies led on the middle and lower northern slope of the LBB (Tournadour, 2015; Chabaud, 2016).A highstand accretion wedge, currently dated to the Holocene, expands at water depths of 177-360 m. Sediment deposition in the prism is mainly the result of hurricanes and density cascading. Its initiation is dated at 13. 6 ± 3.5 ka cal BP, following Meltwater Pulse 1A. Melwater Pulses led to the formationof shallow terraces that enhanced carbonate production and ultimately supplied the prism with sediment through the export of said carbonate. The height of the development of the prism occurred at 6.56 ± 0.9ka cal BP when the sea level reached the shelf-break.Sedimentation in the lower slope is indicative of more pelagic processes, since currents play a greater part in the deposition of sediment than the shelf. Variability in the facies of theses deposits are thus the result of climatic variations (e.g strengthening of currents, influxes of Arctic water). Sediments in this are a share similarities with those in Blake Outer Ridge, 400 km north of the LLB. At water depth of1,300-4,800 m, the slope is scored by a giant canyon, namely the Great Abaco. The morphology of this canyon attests to a structural control of sediment supply: rather than the head of the canyon, tributaries appear to supply the majority of sediment within this system.

The measurement of topography is a key aspect of geomorphology research, and the prevalence of high resolution topographic data predominantly from Light Detection And Ranging (LiDAR) in the past decade has facilitated a revolution in the quantitative study of planetary surface processes. From this increased quality of data, many techniques have been developed to quantify processes occurring at diverse spatial and temporal scales; from the flow of material down a hill-slope to the uplift and subsequent erosion of mountain ranges. Such insights have identified signatures of processes imprinted on landscapes. These include physical processes such as wildfires and landslides, biological processes such as animal burrowing and tree throw, in addition to tectonic uplift and large scale sediment transport. These signatures are observed in both the morphology of hill-slopes and their connection to the channel network, thereby allowing measures of topography to provide quantitative measures of the rates of processes shaping the Earth’s surface. This thesis is concerned with the development and application of reproducible topographic analysis techniques, to yield new insights into hill-slope sediment transport and to provide accurate metrics for quantifying hill-slope properties, including hill-slope length (LH) and relief (R). The measurement of hill-slope length can be performed through the inversion of drainage density, or the analysis of slope-area plots. However, in Chapter 3 I present a method which quantifies the length of hill-slopes through the generation of hill-slope flow paths. The flow path method is shown to be the most reliable of these methods, and is able to provide measurements of the properties of individual hill-slopes, rather than the basin or landscape averaged techniques commonly employed. The topographic predictions of the LH-R relationship of the nonlinear sediment flux law, stating that the rate of sediment transport is nonlinearly dependent on hill-slope gradient, are also tested and contrasted with the predictions of a linear sediment flux law. This provides the first purely topography based test of a sediment flux law. Through the fitting of a prediction of the nonlinear flux derived model to these measurements of hill-slope length and relief, the critical gradient of each landscape, a key parameter in the nonlinear sediment flux law, is also constrained. A nondimensional framework for erosion rate and relief, which allows the comparison of hill-slopes with differing properties in order to identify landscape transience is presented in Chapter 4. This analysis technique builds upon the work performed in Chapter 3, utilizing similar measurements of hill-slope properties, including hill-slope length and relief. The software produced alongside this chapter is shown to reproduce the results of previous studies which have employed this technique. The method is employed on a new landscape in Coweeta, North Carolina where subtle evidence of topographic decay is presented, consistent with models of Miocene topographic rejuvenation in this location. A detailed sensitivity analysis of the technique is performed, highlighting the need for careful parameterization of any analysis, to ensure meaningful results. This method is also employed to estimate an average critical gradient for each landscape, presenting more evidence building upon the evidence presented in Chapter 3 that a broad range of critical gradients exist for any given landscape. The work presented in Chapter 5 attempts to constrain the limits of the geomorphic analyses presented in the previous chapters, when they are applied to low resolution topographic data. A series of topographic datasets are generated at resolutions ranging from 1 to 30 meters upon which topographic analyses are performed. I test two common channel extraction algorithms and find that a simple geometric method, which identifies tangential curvature thresholds in the landscape, provides a more accurate representation of the channel network in low resolution topographic data than a process based method which identifies the topographic signature of channel initiation. The measurement of curvature is also evaluated, and alongside the estimation of diffusivity, is shown to be sensitive to data resolution, however landscape properties also exhibit a strong control on these measurements, where the larger scale curvature signal of Gabilan Mesa, California is more robust than the sharp ridgelines of Santa Cruz Island, California. Finally, the techniques developed in Chapter 3 to measure hill-slope length and relief are tested and are shown to be robust at grid sizes up to 30 meters, with the caveat that an accurate channel network can be constrained.

A caminhada e a corrida são formas de exercício físico que promovem mudanças no estilo de vida, mas, existem muitas controvérsias dos possíveis benefícios e riscos a respeito da caminhada ou corrida quando realizada em diferentes inclinações. O presente estudo teve como objetivo determinar o limiar anaeróbio bem como avaliar e comparar as respostas fisiológicas durante exercícios contínuos (45 minutos) com intensidade correspondente ao limiar anaeróbio executados na esteira rolante nas condições de inclinação positiva (+10%), plano (0%) e inclinação negativa (-10%). Participaram deste estudo 9 mulheres com idades entre 21 e 31 anos, fisicamente ativas. Primeiramente elas realizaram testes crescentes para determinação da intensidade correspondente ao limiar anaeróbio em cada inclinação. Após essa determinação foram realizados os protocolos contínuos na intensidade correspondente ao limiar anaeróbio por 45 minutos. Os resultados encontrados mostraram que o valor médio (\'+ OU -\' desviopadrão) da velocidade correspondente ao limiar anaeróbio no plano foi de 6,56 \'+ OU -\' 0,53 Km/h, na inclinação positiva foi de 5,44 \'+ OU -\' 0,53 Km/h (com redução percentual de 17,07% em relação ao plano) e na inclinação negativa foi de 7,22 \'+ OU -\' 0,67 Km/h (com elevação percentual de 9,14% em relação ao plano). Nos protocolos contínuos foi observado que os valores das variáveis ventilatórias apresentaram-se mais elevados para o protocolo com inclinação positiva, já a freqüência cardíaca apenas apresentou diferença até o 15º minuto do exercício entre os protocolos com inclinação positiva e o protocolo com inclinação negativa. Mas apesar disso, as voluntárias não relataram dificuldade do gesto motor na realização dos exercícios. Conclui-se que mesmo com a tentativa de se trabalhar na velocidade ideal para cada condição imposta, as respostas cardiovasculares e metabólicas são diferentes, ) principalmente entre o protocolo com inclinação positiva e o protocolo com inclinação negativa. O presente trabalho mostrou pontos importantes que devem ser levados em consideração, quanto à escolha do protocolo aplicado nos treinamentos físicos em indivíduos com diferentes condições físicas quando se propõem diferentes velocidades de corrida e inclinações da esteira. / Walking and running are forms of exercise that promote changes in lifestyle, but there are many controversies about the possible benefits and risks regarding the walking or running when performed at different slopes. This study aimed to determine the anaerobic threshold and to evaluate and compare the physiological responses during continuous exercise (45 minutes) with intensity corresponding to anaerobic threshold run on the treadmill in terms of positive slope (+10%), level (0%) and negative slope (-10%). The study included 9 women aged between 21 and 31 years old, physically active. First they performed increasing intensity tests to determine the intensity corresponding to anaerobic threshold on each slope. After determining these parameters the continuous protocols were performed in intensity corresponding to anaerobic threshold for 45 minutes. The results showed that the speed average (\'+ OU -\' standard deviation) at level the anaerobic threshold was 6.56 \'+ OU -\' 0.53 km/h, atthe positive slope was 5.44 \'+ OU -\' 0.53 km/h (with a percentage reduction of 17.07% over the level) and the negative slope was 7.22 \'+ OU -\' 0.67 km/h (with high percentage of 9.14% over the level). In continuous protocols was observed that the values of ventilatory variables were more elevated for the protocol with positive slope and the heart rate showed only significant difference until the 15th minute of exercise between protocols with positive slope and with negative slope. But despite this, the volunteers reported no difficulty in motor gesture in exercises. It was conclude that even with the attempt to run at ideal speed for each condition the cardiovascular and metabolic responses are different, especially between the protocol with positive slope and with negative slope. This study showed important points that should be taken into account in the choice of protocol used in physical training in individuals with different physical conditions when they propose different running speeds and inclinations of the treadmill.

Esta dissertação apresenta o estudo sobre um caso de movimento rotacional em uma massa de solo coluvionar, localizada na Vila Albertina na zona norte da cidade de São Paulo-SP. O objetivo deste trabalho foi estudar os processos de instabilidade associados a eventos de chuvas, condições de fluxo e ações antrópicas que ocorreram no local. Procurou-se estabelecer as relações de causa e efeito que os eventos pluviométricos têm sobre a estabilidade da encosta; também foram estudadas as alterações causadas pelo homem e as condições de infiltração de água no terreno. Foi realizado um levantamento histórico de escorregamentos ocorridos na região desde a década de 30. Este levantamento histórico constituiu em resgatar aerofotografias, imagens de satélites e reconstituições de plantas topográficas do local. Através deste estudo se constatou que a encosta começou a ser modificada desde a década de 40, com uma possível tentativa de exploração de rochas graníticas. Nos anos 60 foi construída uma fábrica no pé da encosta. Atualmente, o solo desta encosta, que está em movimento, invade o pátio desta fábrica. Na década de 70, a área de escorregamento começou a ser ocupada por moradores, que construíram suas casas sobre esta encosta. Esta ocupação foi desordenada e acelerou o processo de instabilização da encosta; até o ano de 2004 viviam no local 600 famílias. No início da década de 80, a encosta apresentou grandes movimentações. Para que estes movimentos fossem cessados, realizaram-se obras de contenção, foram executados retaludamentos, instalações de drenos profundos e drenagens superficiais através de canaletas e escadas hidráulicas. Ainda na década de 80, retirou-se uma grande camada de solo da encosta para cobrir o aterro sanitário da Vila Albertina, localizado no terreno vizinho a encosta. Esta remoção deixou parte do terreno plano, causado o acumulo de águas pluviais. As águas, que antes escoariam superficialmente, passaram a se infiltrar no terreno. Para a caracterização e obtenção dos parâmetros de resistência dos solos da região, foram coletadas três amostras indeformadas: uma na crista do escorregamento e duas no pé da encosta. Neste local, foram identificados um solo coluvionar e um solo residual mais jovem. A encosta foi instrumentada através de marcos superficiais, inclinômetros que também serviram de medidores de nível d\'água e tensiômetros. / This paper presents a study on a rotational movement in a colluvial soil mass located at Vila Albertina, northern region of São Paulo City. The main purpose of this work is to study the processes of instability related to rainfalls, conditions of flow and human actions that occurred at the site. It was intended to establish cause and effect relations pluviometric events have over the stability of the slope. It also studies alterations caused by men and water infiltration conditions on the land. A historical survey of ground sliding data on the region since the 1930s was gathered. This survey was composed of retrieved material such as aerial photographs, satellite images and topographic plans reconstitutions of the location. By means of this study, it was possible to verify that the slope started to be modified since the1940s, with a possible attempt of granite rocks exploitation. In the 60s, a factory was built on the bottom of the slope. Nowadays, the soil of this slope, which is in movement, is invading the courtyard of this factory. In the 70s, the sliding area started to be occupied by inhabitants, who built their homes on this slope. This disorderly occupancy accelerated the instability of the slope; until 2004, 600 families were living in the location. In the beginning of the 80s, the slope presented considerable movements. In order to stop them, contention constructions were executed, as well as re-sloping, installation of deep drains and superficial drainage by channels and hydraulic stairs. Still in the 80s, a great layer of the slopes soil was taken to cover Vila Albertinas sanitary landfill, located at land nearby. This removal left part of the ground plain, causing an accumulation of pluvial water. The pluvial water, which would superficially drain, started to infiltrate into the ground. To characterize and acquire the regions soil resistance parameters, three undisturbed samples were collected: one at the top of the sliding and two at the bottom of the slope. In this area, colluvial and a more recent residual soil were identified. The slope was monitored by superficial indicators, tensiometers and inclinometers that were also used to measure the water level.

Deslizamentos em solos tropicais são frequentemente resultados do avanço de uma frente de umedecimento devido às águas das chuvas. O avanço desta frente de umedecimento provoca elevação da poro-pressão de água ou redução da sucção, e consequentemente, perda de resistência do solo. Este trabalho apresenta um estudo sobre a resistência ao cisalhamento dos solos não saturados, abrangendo uma fase experimental envolvendo ensaios de caracterização, resistência e obtenção das propriedades hidráulicas dos solos e um estudo numérico, com o objetivo de verificar o comportamento da poro-pressão no interior de um talude e a influência na sua estabilidade. Os ensaios de resistência foram realizados no aparato de cisalhamento direto, para a condição inundada, e no aparato de compressão simples com medida direta de sucção, por meio do tensiômetro de alta capacidade (TAC), para a condição não saturada. O equipamento TRIFLEX 2 foi utilizado para se determinar os coeficientes de permeabilidade na condição saturada, e as curvas de retenção foram obtidas utilizando-se a placa de sucção, o TAC e o método do papel filtro. A partir dos resultados obtidos na fase experimental, avaliou-se a influência das características das precipitações (duração e intensidade), condições inicias de sucção no talude e das propriedades hidráulicas dos solos na variação da poro-pressão de água, no interior do talude, ao longo do tempo. Paralelamente à variação da poro-pressão de água, foi obtida a variação do fator de segurança durante e após a precipitação. / Landslides in tropical soils are often the result of advance of the wetting due to rainfall. This advance results from an increase in pore water pressure, reduction in present soil matric suction, reduction in the shear strength of the soil. This work will present a study related to the shear strength of unsaturated soils, including an experimental study, involving characterization, shear strength tests and obtaining hydraulic characteristics of the soils. There is also a numeric study with the aim to analyze the pore water pressure behavior in slopes and its influence in the slope stability. The shear strength tests were carried out in the direct shear test device, for the flooded condition, and concerning the unconfined compression with direct measured matric suction using a high capacity tensiometer (HCT) placed at the base of the sample, for the unsaturated condition. The permeability tests were carried out with TRIFLEX 2 device, and the retention curves were determined using suction plate, HCT and filtered paper. The experimental data permitted the evaluation of the influence of the characteristics of the rainfall (duration and intensity), initial conditions of the slope and of the hydraulic characteristics of the soils in the pore-pressure change of water in the slope, during the test time. In parallel to the pore pressure change of water, the variations of the safety factors during and after the rainfall were obtained.

Taludes formados por solos na condição não saturada são muito comuns no Brasil. Nestes casos a poro-pressão de água contribui para a estabilidade desses taludes. Este trabalho pretende avaliar o efeito do tipo de revestimento superficial na alteração do perfil de poro-pressão de água provocado por fluxos gerados a partir de precipitações, evaporação e evapo-transpiração, e conseqüentemente na estabilidade de talude experimental. São apresentadas aqui as características geológico-geotécnica, geomorfológica, climática e pluviométrica de campo experimental implantado na zona leste de São Paulo/SP, onde foram instalados e monitorados tensiômetros, pluviômetro e medidor de nível dágua por um período oito meses. Resultados de ensaios de caracterização, resistência e obtenção das propriedades hidráulicas dos solos que compõem o maciço estudado são analisados, assim como ensaios realizados com a argamassa de revestimento do talude, ensaios para a análise do funcionamento dos tensímetros e tubos tensiométricos utilizados no monitoramento, e outros ensaios realizados in situ. O monitoramento realizado indicou coerência entre precipitações e variação da poropressão de água, e variação do nível dágua do terreno, em ambos os tipos de revestimento superficial, vegetação natural e argamassa, nos dois tipos de solo presentes no maciço. Análises de estabilidade do talude indicaram o efeito do tipo de revestimento superficial e das variações sazonais de poro-pressão de água no fator de segurança ao escorregamento do talude. / Slopes formed by unsaturated soils are very common in Brazil. In these cases porewater pressure contribute for the slope stability behavior. This work aims at evaluating the effects of types of superficial coating on the profile of pore-water pressure changes, due to flow generated by precipitation, evaporation and evapotranspiration, and consequently on the stability of a experimental slope. It is presented here the geological-geotechnical, geomorfological, climatic and pluvial characterizations of the experimental field located in the east zone of São Paulo/SP, where have been installed and monitored tensiometers, pluviometer and groundwater level measurer during eight months. Results of tests of characterization, shear strength, and for obtaining the hydraulic properties of the in situ soils are analyzed, as well as the tests carried out with de mortar applied over the slope, as well as the functionality tests for the tensimeters and tensiometric tubes used on the monitoring, as well as other in situ tests. Monitoring indicated coherence between precipitation and change in pore-water pressure profile, and groundwater level, in both types of superficial coatings, natural vegetation and mortar, and in both types of in situ soils. Stability analyzes indicated the effect of the type of superficial coating and of the variation of pore-water pressure profile, during the experiment, on the factor of safety of the experimental slope.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-11T20:50:25Z No. of bitstreams: 1 2012 - Fernando Soares Gon?alves.pdf: 1312529 bytes, checksum: f74571a02ea2e60ea594e27896515023 (MD5) / Made available in DSpace on 2017-04-11T20:50:25Z (GMT). No. of bitstreams: 1 2012 - Fernando Soares Gon?alves.pdf: 1312529 bytes, checksum: f74571a02ea2e60ea594e27896515023 (MD5) Previous issue date: 2012-04-16 / CAPES / Mining activities have a direct influence on economic development, which directly affects the gross domestic product (GDP), mainly in developing countries. The environmental interference provided by the mining activities can vary in intensity according to the mineral exploited, but they are always punctual activities. This study was conducted in the mineral province of Caraj?s, PA, in areas revegetated post mining iron ore, and to evaluate the processes of vegetation arising from revegetation of barren slopes, starting from the initial hypothesis that signed the revegetation of slopes of waste in the mining of iron using cocktails of seed species in the rainforest and savanna Metal?fila can act as facilitators of natural succession and conditioners as the substrate. The second hypothesis is that signed the removal, storage and return of surface soil organic horizon ("topsoil") after the operation by open pit mines have an essential role in the revegetation process, because they already provide quantitative and qualitative characteristics that reflect the communities previously existing in the area. In this work were highlighted four areas of study, three areas undergoing revegetation and an area with the presence of primary forest. The variables analyzed were phytosociology, photosynthetically active radiation, chemical quality of the stock of litter, soil fauna and soil fertility. The results indicate that the revegetation processes used, promoted the formation of a plant community which facilitates the process of succession over time, as many of the species used in the cocktail of seeds of the CCI and workshop areas are being replaced by species more adapted to conditions of each site. In the area called Hoppe, the herbaceous species that colonized the area are being replaced by shrub and tree species. The quality of the provided information able to litter cluster areas of studies according to the nutrients present in the litter, the areas being divided into Workshop CCI and the concentrations of lignin, cellulose, P and Mg, while areas were grouped Hoppe and Mata as a function of P and N fractions present in the twigs and leaf litter. But the use of soil fauna indicated that the groups Collembola and Formicidae will be extremely important for monitoring the quality of sites over time. From these results it was concluded that the use of biotic and abiotic indicators in studies of recovery of mined areas should be thoroughly studied and documented, they offer attributes able to understand developments in the recovery process. / As atividades de minera??o t?m influencia direta sobre o desenvolvimento econ?mico, afetando diretamente o produto interno bruto (PIB), principalmente dos pa?ses em desenvolvimento. As interfer?ncias ambientais proporcionadas pelas atividades de minera??o podem variar de intensidade de acordo com o mineral explorado, mas sempre s?o atividades pontuais. O presente estudo foi realizado na prov?ncia mineral de Caraj?s-PA, em ?reas revegetadas p?s minera??o de min?rio de ferro, tendo como objetivo avaliar a forma??o vegetal oriunda dos processos de revegeta??o de taludes de est?ril, partindo da primeira hip?tese firmada que a revegeta??o dos taludes de est?ril em ?rea de minera??o de ferro utilizando coquet?is de sementes de esp?cies pertencentes a savana metal?fila e floresta ombr?fila podem agir como facilitadores da sucess?o natural e como condicionadores do substrato. A segunda hip?tese firmada ? que a retirada, armazenamento e retorno do horizonte org?nico superficial do solo (?topsoil?) ap?s a explora??o por minera??es a c?u aberto t?m fundamental papel no processo de revegeta??o, por j? apresentar caracter?sticas quantitativas e qualitativas que refletem as comunidades anteriormente existentes na ?rea. Neste trabalho foram demarcadas quatro ?reas de estudo, sendo tr?s ?reas em processo de revegeta??o e uma ?rea com presen?a de mata prim?ria. As vari?veis analisadas foram fitossociologia, radia??o fotossinteticamente ativa, qualidade qu?mica do estoque de serrapilheira, fauna do solo e fertilidade do solo. Os resultados obtidos apontam que os processos de revegeta??o utilizados, promoveram a forma??o de uma comunidade vegetal que viabilize o processo sucessional ao longo do tempo, pois muitas das esp?cies utilizadas no coquetel de sementes das ?reas CCI e Oficina est?o sendo substitu?das por esp?cies mais adaptadas ?s condi??es de cada s?tio. Na ?rea denominada Hoppe, as esp?cies herb?ceas que colonizaram a ?rea est?o sendo substitu?das por esp?cies arbustivas e arb?reas. A qualidade da serrapilheira forneceu subs?dios capazes de agrupar as ?reas de estudos em fun??o dos nutrientes presentes na serrapilheira, sendo as ?reas CCI e Oficina agrupadas em fun??o das concentra??es de lignina, celulose, P e Mg, enquanto que as ?reas Hoppe e Mata ficaram agrupadas em fun??o do Ca e N presente nas fra??es galhos e folhas da serrapilheira. J? a utiliza??o da fauna do solo indicou que os grupos Collembola e Formicidae ser?o de extrema import?ncia para o acompanhamento da qualidade dos s?tios ao longo do tempo. A partir destes resultados foi poss?vel concluir que a utiliza??o de indicadores bi?ticos e abi?ticos em estudos de recupera??o de ?reas mineradas devem ser amplamente estudados e documentados, pois oferecem atributos capazes de compreender a evolu??o nos processos de recupera??o.

Long linear earthwork assets constructed in high-plasticity overconsolidated clay are known to be deteriorating due to long-term effects of wetting and drying stress cycles as a result of seasonal weather patterns. These stress cycles can lead to shallow first-time failures due to the mobilisation of post-peak strength and progressive failure. Design requirements of new earthworks and management of existing assets requires improved understanding of this critical mechanism; seasonal ratcheting. Incremental model development and validation to allow investigation of multiple inter-related strength deterioration mechanisms of cut slope behaviour in high-plasticity overconsolidated clay slopes has been presented. Initially, the mechanism of seasonal ratcheting has been considered independently and a numerical modelling approach considering unsaturated behaviour has been validated against physical modelling data. Using the validated model, the effects of slope geometry, design parameter selection and design life have been considered. Following this, an approach to allow undrained unloading of soil, stress relief, excess pore water pressure dissipation, seasonal ratcheting and progressive failure with wetting and drying boundary conditions has been considered. Hydrogeological property deterioration and the potential implications of climate change have been explored using the model. In both cases the serviceable life of cut slopes is shown to reduce significantly in the numerical analyses. Finally, a model capable of capturing hydrogeological behaviour of a real cut slope in London Clay has been developed and validated against long-term field monitored data. Using the validated model, a climate change impact assessment for the case study slope has been performed. The numerical analyses performed have indicated that seasonal ratcheting can explain shallow first-time failures in high-plasticity overconsolidated clay slopes and that the rate of deterioration of such assets will accelerate if current climate change projections are representative of future weather.