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The growing demand for space and financial resources to manage current and new municipal solid waste (MSW) landfills has become a massive challenge for several countries. Additionally, landfills contribute to adverse environmental impacts such as pollution and COfx1.

The moisture content of the municipal solid waste (MSW) is a physical characteristic that plays a fundamental role in the stability and settlement of landfills. However, this physical index is difficult to monitor within the mass of landfilled MSW because it undergoes great variation due, mainly, to the heterogeneity and biodegradation of the waste. Brazilian MSW generally has a large amount of organic matter, that when biodegraded, generates a considerable volume of gases and fluids, aggravated by climatic conditions, such as high rainfall and temperatures. Hence, the importance of obtaining and evaluating the distribution of moisture content in the MSW mass over time. Currently, the electrical resistivity properties have been presented as an interesting approach to obtain the moisture content in landfills indirectly. This study aimed to apply geoelectrical methods as a tool to obtain and evaluate the moisture content distribution in an experimental cell of a sanitary landfill using Archie's law, which correlates the volumetric moisture content and electrical resistivity. Moisture content values were obtained in laboratory tests with MSW samples collected in two vertical holes and electrical resistivity measurements by means of vertical electrical sounding. The moisture content and the resistivity values of the samples were used to calculate the parameters a and m of Archie's law. This allowed to convert the resistivity tomography to moisture content tomography. The good correlation achieved between the moisture content calculated by Archie's law and that obtained from samples indicates that the use of electrical resistivity methods is useful to assess and monitor quantitatively the moisture content in landfills using Archie's law.

The disposal of Municipal Solid Waste (MSW) in sanitary landfills produces leachate, whose composition changes depending on the microbial community and the environmental conditions. However, these changes cannot be observed in sanitary landfill because of the superposition of cells, which makes it difficult to determinate the relationship among the phases of biodegradation of MSW, the composition of the leachate and the time required for complete stabilization of the waste. This illustrates the importance of building experimental cells that simulate landfill to monitor the leachate over a long period. This study aimed to analyze the composition of the leachate generated from an experimental cell built on the Delta A sanitary landfill of Campinas City, Brazil, over 945 days. The leachate showed a transition from an acidic anaerobic phase to a methanogenic phase within approximately 100 days. By the one-hundredth day, the leachate showed a characteristically low pH, between 5.0 and 6.0 and a high Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) such as a young leachate with high biodegradability. Moreover, there was an intense leaching of the metals Cd, Fe, Pb and Mn, with concentrations higher than those allowed for the release in water bodies, according to Brazilian law. After the one-hundredth day, the leachate was characterized as stabilized. The pH increased and the concentration of volatile fatty acid, COD and BOD decreased. Co, Zn, Ni and Cu were leached. The potentially toxic metal concentrations found in the leachate also were above the values allowed by Brazilian law.

Gravitational mass movements are processes of solid matter transport and exogenous modelling of the relief. In Brazil, the landslides are the most common type, for its climatic and geological dynamics, triggered mainly by rainfall. Particularly, Serra do Mar has become a scene of great incidence these events, due to its climatic, geological and geomorphological characteristics. This research has the objective to develop the modelling of soil-water retention curves of the soil samples collected from B e and C-horizons of four open trenches in a hillside from the Serra do Mar. The soil-water retention curves were studied with drying and wetting pathways. It is aimed to understand of the water flow and possible destabilization processes in the hillside.

The sanitary landfills in Brazil are, generally, characterized by their high organic material content (around 60%), presence of different types of mixed wastes, and low compaction energy, which differentiates them from the landfills of developed and high-income countries. To prevent environmental and slope stability risks, it is crucial to understand the behavior of such landfills and the changes in their physical properties over time. The compression wave velocity (Vp) and shear wave velocity (Vs) are important parameters to subsidize the mechanical characterization of sanitary landfills, using which can be derived the dynamic elastic properties of municipal solid waste (MSW) for stability analysis. Using the geophysical methods of seismic refraction, active and passive multichannel analysis of surface waves, and crosshole test, it was obtained the values of Vp and Vs by employing an experimental cell and a lysimeter filled with MSW in the City of Campinas, São Paulo State, Brazil. The results obtained from the crosshole test showed that Vp ranged from 217 to 252 m/s and Vs ranged from 86 to 89 m/s. These low values can be attributed to the high content of organic material, low compaction energy, and climatic conditions such as high pluviometry index and high temperatures that together lead to changes in the pore fluid saturation, effective stress, and pore pressure. These values are indicative of the lower limit of the corresponding velocities reported in most literature; however, they are in accordance with the values reported for landfills located in countries with similar socioeconomic and climatic conditions.

Os movimentos gravitacionais de massa são processos de modelagem exógena do relevo, que em especial no Brasil, são deflagrados principalmente pelos altos índices pluviométricos. A área estudada localizada na Morraria da Ilha de São Vicente, entre os morros Chico de Paulo e Saboó, no município de Santos, é uma área representativa destes processos, haja visto o alto índice pluviométrico e seu histórico de grandes acidentes relacionados a estes fenômenos. Dessa forma, este trabalho a partir de análises envolvendo os limites de consistência, granulometria (com e sem defloculante) e umidade natural, colaboraram para a compreensão tanto do comportamento microagregado da argila, quanto dos materiais constituintes de cada horizonte, de forma a influenciar na estabilidade da encosta.

This research presents and analyzes the results of Soil Water Characteristic Curves (SWCC) for the soil horizons (A, B and C) of two different trenches (TR3 and TR7) opened along a slope located in the Serra da Mar mountain range, Brazil. Microaggregations were observed in soil horizons of both trenches, which changed the textural classification of the soils. TR7 showed more macropores than TR3, especially on horizon C. Unimodal SWCC were obtained for soils of the horizon A for both trenches. Instead, bimodal SWCC were obtained for soils of the deeper horizons (B and C). All soil horizons showed the phenomenon of hysteresis, and it’s more expressive in the macroporosity part. In TR7 the water retention capacity is lower in B and C, facilitating the drainage, however, horizons B and C of TR3 presented greater water retention capacity for the same matric suction value. Depending on the intensity and duration of rainfall, the horizons B and C of both trenches may suffer a decrease of shear strength, without necessarily saturating. The A horizon of TR3 can undergo an erosive process for heavy and short rains.

In many developing countries, a landfill remains one of the most extensively employed solid waste disposal solutions. Although a landfill is a well-designed engineering system, the base lining of a landfill may perform poorly and allow the leachate to reach the underlying soil layers and groundwater. Leachates contain a variety of toxic and hazardous contaminants, which are attenuated in the soil by various processes that slow or transform them. Thus, the objective of this research was to study the water and leachate permeability and retention of the liner soil in a landfill experimental cell by subjecting it to geotechnical, chemical-mineralogical, and physicochemical characterizations, water and leachate permeability tests, and mercury intrusion porosimetry (MIP). In addition, the water and leachate retention curves were determined and analyzed using RETention Curve (RETC) software to obtain the unsaturated permeability curves. The leachate in the soil decreased the suction considering the moisture content of the compacted soil in the field, which consequently increased the leachate permeability of the mineral liner. For the same suction value, in the drying pathways, the soil retained a greater amount of distilled water than leachate. In the wetting pathways, the opposite occurred. Microorganisms were detected in the soil during the filter paper test. The permeability coefficients of the unsaturated soil were directly proportional to the gravimetric moisture content for the water and the leachate, which demonstrated that the soil presents lower unsaturated permeability coefficients for water than for leachate for the same water content.

In Brazil, conventional covers of sanitary landfill are consisted of fine soils compacted with tractor treadmill. Nonetheless, some clays have swelling behavior and present shrinkage cracking when they are dry, impairing their performance with relation to control the flow of water into the waste mass and the flow of gases out of the waste mass. This control is necessary to minimize the leachate and gas volume generated into de waste mass. This research aimed to evaluate the performance of two conventional covers of two lysimeters filled with municipal solid waste (MSW) of Campinas city, Brazil. For this, the concentration of gases (CO2 and CH4) that was coming out of covers was obtained using flux chamber and correlate with the concentration of gases that were drained by central pipe. Disturbed soil samples from two covers were characterized by geotechnical tests such as grain-size distribution, consistent limits, unit weight and moisture content. Permeability testes were also performed with specimens trimmed of undisturbed soil samples collected of two covers. The soil samples were classified as silt clayed-sandy and they presented micro aggregation. Saturated permeability coefficients presented orders of magnitude of 10−4 and 10−5 cm/s. Gas concentrations from central drain were greater than gas concentrations from the cover, twice for CO2 and 30% for CH4, approximately. The precipitation influenced the gas concentrations from central drain and from covers differently and this fact is discussed.

Municipal solid waste (MSW) permeability is influenced mainly by compaction, unit weight, overburden pressure, composition, and biodegradation of the waste. However, the variation of hydrau...

The Ore Treatment Unit (UTM-Caldas), in the city of Caldas, Minas Gerais, Brazil, nowadays in decommissioning stage, was the first uranium extraction mine in Brazil. Several negative environmental impacts in the area have occurred, because of mining, treatment and beneficiation processes. Waste rock pile 4 (WRP-4) generates acid mine drainage (AMD), which is discharged in the Nestor Figueiredo retention pond (NFP). However, leakage of acid water by the NFP dam foundation has been constantly observed. Therefore, this research aimed to investigate a typical tropical soil, in order to use it as mineral liner for the NFP to minimize the leakage of acid water through the dam foundation and to retain predominant chemical species. Geotechnical, chemical and mineralogical tests were performed to characterize the soil and a column test was carried out using the acid mine drainage as contaminant, which contained aluminum (Al), manganese (Mn), iron (Fe) and fluoride (F-). The soil presented micro aggregation, acid pH, and low values of organic matter content and cation exchange capacity, which are characteristics of highly weathered soils. Diffusion was the predominant transport mechanism in the column test. Effluent solutions with pH less than 6.0 indicated the formation of insoluble Al-F complexes in the soil and desorption of iron and manganese at concentrations above those allowed by the Brazilian legislation. At pH greater than 6.0, the desorption of iron and manganese and release of aluminum and fluoride in the free form occurred, with concentrations also higher than the allowed by the Brazilian legislation.

The research studies the applicability of two elastoplastic models for the collapse prediction of the lateritic soil profile from Southeastern Brazil. These tropical soils have peculiar geotechnical behavior, due to their mineralogical composition and porous structure coming from intense process of formation. Two elastoplastic models were analyzed: the Barcelona Basic Model (BBM) and another one based on BBM, however developed for tropical soils. Oedometric tests with suction control were performed at three distinct depths of the soil profile. The BBM was not suitable for the upper layer of the soil profile, because BBM considers the compressible behavior of the soil in function of the reduction of the elastoplastic compressibility index with the increase of the matric suction. The model developed for tropical soils showed better suited to the compressible behavior of the soil profile, resulting in good prediction of the collapse potential, mainly by accepting increasing values of the elastoplastic compressibility index of the soil profile with the matric suction rise.

This paper aims to propose structural models for understanding the collapsibility of a colluvial and lateritic soil by conducting oedometric tests with controlled suction executed in laboratory. The undisturbed soil samples submitted to experiments were collected by opening a trial pit in Experimental Field for Soil Mechanics and Foundations situated at the State University of Campinas, Sao Paulo, Brazil. The soil samples were characterized by means of standard geotechnical tests, chemical and mineralogical tests and mercury intrusion porosimetry. Oedometric tests with controlled suction showed the influence of matric suction on the compressibility of the soil samples. It was also observed that the higher the values of matric suction, the higher the Laboratory Collapse Potential — CP. The mineralogical chemical tests indicated the presence of oxides and hydroxides of iron in the samples, compounds usually associated with cementation. The presence of mineral, such as kaolinite, gibbsite, hematite and goethite, was also observed. The impregnated thin-layer plates of the soil samples, as well as the grain-size distribution curves and mercury intrusion porosimetry, indicated the presence of a structure formed by microaggregates. Structural models for soil collapse were proposed basing on the results obtained. There were behavioral differences in each soil sample collected at different depths. The behavior of the sample collected at a 1.5 m depth was basically influenced by matric suction. As for the samples collected at 4.5 m and 6.5 m, besides being both influenced by matric suction they were also influenced by the presence of cementing agents (samples collected at 4.5 m) and by the presence of more angular grains of quartz (samples collected at 6.5 m).

This study aims to determine and to model the relationship of matric suction versus water content, known as soil–water characteristic curve (SWCC), for a tropical soil profile at the southeastern Brazil. This soil profile consists of a colluvial, lateritic silty clay, with thickness of about 6.5 m. The filter paper and pressure plate techniques were used to determine the SWCC. Specimens were trimmed from the undisturbed soil samples collected along soil profile depth and submitted to drying paths. Impregnated thin-layer plates and a petrographic microscope were used to examine the structure and mineralogical composition of the soil samples. Mercury intrusion porosimetry tests were performed on some soil samples to obtain the frequency histogram of the pores. SWCC with bimodal pore-size distribution were obtained by the filter paper technique and SWCC with unimodal pore-size distribution were obtained by the pressure plate technique. The SWCC showed values of air-entry ranging from 1 to 3 kPa, depending on the technique used, resembling soils with macroporosity, as the lateritic soils. Combining both techniques, the SWCC could be fitted by a model that takes into consideration soils with macro and microporosity.

The behavior of pile foundations subjected to horizontal loading is typically evaluated using horizontal load tests. Although load tests are valuable to understand site-specific soil-structure interaction phenomena, validated predictive methods are also useful during the design phase. In this study, the results from horizontal load tests are compared with methods which predict the horizontal bearing capacity of piles using in situ measurements of soil behavior. Specifically, several horizontal load tests were performed in order to evaluate the behavior of two 12-m long Strauss piles and four bored piles with similar length, all installed in a lateritic soil profile. Two prediction methods were evaluated using p-y curves computed from the results of Marchetti's dilatometer test DMT results. The predictive methods using the p-y curves from the DMT showed good agreement with the behavior observed in the pile loading test.

Some peculiarities of water retention in a tropical lateritic soil of clayey nature are presented and discussed. The typical soil microstructure is shown through thin-layer plates emphasizing soil microaggregation and pore distribution and their repercussion on the soil-water retention curve and on hysteresis. It is shown that the clayey soil has a behavior that to a large extent resembles sandy soil, which is characterized by the relatively high saturated hydraulic conductivity, low air-entry value, and small suction range at which water drainage takes place. The severe weathering processes that originated this soil have produced an altered soil that seems to be homogeneous in terms of physical indices, hydraulic conductivity, and soil-water retention characteristics, up to 4.5 m in depth.

This work presents a comparative analysis about the behaviour of pile caps supported by 3 piles subjected to axial loading. Piles with 20 cm and 30 cm diameters were analysed. The main reinforcement was maintained in all the specimens, however, the arrangement of the secondary reinforcement varied. The main reinforcement consisted of steel bars connecting the piles. The secondary reinforcement was made up of: (a) bars going through the piles and through the projection of the column, (b) bars forming a network, and (c) vertical and horizontal stirrups. The main objective was the observation of the pile cap behaviour regarding the cracks and the modes of rupture. The real scale specimens were subjected to experimental tests until failure by rupture. Instruments were placed with the aim to obtain the displacement of the bases, the strains in the main and secondary reinforcement bars, in the compression struts, in the lower and upper nodal zones and in the sides of the caps. None of the caps reached failure by rupture with a load less than 1.12 times the theoretical load. The specimens ruptured due to the cracking of the compression strut and/or the yielding of the reinforcement bars in one direction.

Este trabalho estuda o comportamento de blocos rígidos sobre três estacas, submetidos à ação de força centrada, conservando a armadura principal, porém, variando as armaduras secundárias e adotando-se estacas de diâmetros de 20 cm e 30 cm. A armadura principal foi constituída por barras unindo as estacas. As armaduras secundárias foram constituídas por barras passando pelas estacas e projeção do pilar, distribuídas em forma de malha e por estribos verticais e horizontais. O objetivo principal foi o estudo do desenvolvimento das fissuras e o modo de ruína, através de ensaios experimentais em escala real. A instrumentação foi realizada de modo a se obter deformações nas barras das armaduras principais e secundárias, nas bielas de compressão, nas zonas nodais inferior e superior e nas faces laterais do bloco, em função da força aplicada no pilar e das reações das estacas. Além do estudo experimental, foi desenvolvida análise numérica tridimensional e não linear, pelo método dos elementos finitos, considerando os mesmos elementos estruturais, embora sem considerar as armaduras. Esta análise se concentrou no progresso das tensões normais principais, das deformações totais e plásticas principais e dos deslocamentos relativos às forças característica e de cálculo, previamente estimadas por métodos usuais de dimensionamento. Nenhum modelo experimental atingiu a ruína com força menor que a força teórica. Os modelos romperam por fendilhamento das bielas comprimidas de concreto acompanhado pelo escoamento das barras da armadura em uma direção. Os blocos com estacas de diâmetro de 20 cm apresentaram maiores deformações de tração transversais às bielas de compressão Experimental tests were executed to study the behavior of rigid reinforced concrete three-pile caps subjected to patches of loading on the center top surfaces of the column. Three-pile caps were designed with the same geometry, dimensions and principal reinforcement layout, but different secondary reinforcement layouts and diameter of the piles. The load applied to the pile cap and the load carried by each pile were measured using load cells. Electrical resistance strain gages were installed along selected bars to measure the strain on the centers of reinforcing bars, compression struts and superior and inferior nodals zones, in function of both craking load and ultimate load. Moreover, an investigation to study the behavior of these non-reinforced concrete three-pile caps by a three-dimensional non-linear finite element analysis was presented. Some of the theoretical results were compared with those obtained from experiments and this analysis showed compatibility. All tests ultimate loads were higher than of ones of theoretical loads. Specimens failed longitudinally after a compression strut split due to the transverse tension caused by spreading of the compressive stresses, and yielded reinforcing bars in one direction

The first uranium extraction mine of Brazil, nowadays found in decommissioning phase, has caused several negative environmental impacts in its area, as a result of mining, treatment, and beneficiation processes. The generation of acid mine drainage in waste rock pile 4 (WR-4) is one of the negative impacts with the most critical situation. The acidic water, product of this drainage, presents heavy metals and radioactive elements and it may be infiltrated by the basis of the impoundment basin, where this water is collected for treatment. The objective of this study was to investigate a typical tropical soil, located in the area of Ores Treatment Unit of Caldas in the southwestern state of Minas Gerais, Brazil, in order to use it as a mineral liner for a retention basin to minimize leakage of acidic water through the foundation of a containment dam. In this way, geotechnical, chemical, and mineralogical tests were performed in order to characterize a soil sample collected in the area. In addition, adsorption tests were conducted with solutions of aluminum (Al), manganese (Mn), and iron (Fe), and with and without adjustment of the initial pH (pHto) of the solutions. The results indicated a well-weathered soil composed of kaolinite, gibbsite, and iron oxides. The adsorption tests showed different behaviors for Al, Mn, and Fe considering or not the adjustment of the pHto. Aluminum showed low adsorption by soil; because of this, only the adsorption isotherms of Mn and Fe for test with adjustment of the pHt0 were determinate. The coefficient of distribution (K D) of Mn was 0.0364 L g−1 and Fe 0.0281 L g−1. As for the retardation factor (R d), its values ranged from 81 to 91 for Mn and from 61 to 79 for Fe, considering different behaviors of the adsorption isotherm models.

The increasing consumption in emerging countries like Brazil has caused the increased generation of municipal solid waste (MSW) and hence the demand for environmentally friendly and relatively inexpensive disposal of the waste, such as sanitary landfills. In this research, it is presented the gravimetric composition of MSW disposed in a large-scale experimental cell, built on a sanitary landfill, Campinas, state of Sao Paulo, Brazil. For such, it was adopted the hypothesis that the characteristics of MSW vary with the income level of the population and the type of activity that generates it (domestic or commercial). Twenty-two tests were performed for gravimetric characterisation. Statistical analyses considering the results of this characterisation showed that the adopted hypothesis was correct. The MSW composition was preponderant by organic matter (52.7%), paper (17.5%) and plastic (13.0%). The methodology used was considered feasible to achieve the proposed objective of the characterisation.

Os metais potencialmente tóxicos são elementos de natureza não biodegradável, fácil absorção pelos organismos e com grande capacidade de bioacumulação e que, normalmente, estão presentes nos lixiviados de aterros sanitários. Por conta disso, as barreiras de baixa permeabilidade nessas estruturas são elementos fundamentais para proteção ambiental. Essas barreiras, comumente, são feitas de solos argilosos compactados (CCL), por atender aos requisitos de condutividade hidráulica (K) e retenção de contaminantes. Na ausência de solos argilosos, viabilizar o uso de solos arenosos para esta aplicação é de grande interesse. Por conta disso, a presente pesquisa teve por objetivo aplicar uma técnica de melhoria à solos arenosos, adicionando cimento e argila, para avaliar o comportamento de K e o Fator de Retardamento (Rd) de contaminantes nas misturas solo-cimento-caulim (SCC) e solo-cimento-bentonita (SCB). Para isso, foram realizados os ensaios de: caracterização física, físico-química e mineralógica do solo, dos materiais argilosos e das misturas; ensaio de coluna para avaliar K com a percolação de água e solução de CuCl2.2H2O (0,012M e 0,024M) e o Rd do Cu2+; e o ensaio de equilíbrio em lote (batch test), nas concentrações de 0,005M, 0,012M e 0,024M, para avaliar o Rd obtido e comparar com o Rd do ensaio de coluna. Ao avaliar K com a percolação de água, observou-se que se o teor de umidade aplicada for acima da umidade ótima da mistura, a eficiência da compactação é comprometida e faz com que os valores de K sejam maiores. As misturas SCB e SCC atenderam os requisitos de K normatizados para aplicação como barreiras de fundo em aterros sanitários, com valores médios de 3,7x10-10 e 5x10-10 m/s, respectivamente. Durante a percolação da solução contaminante, houve redução de K em SCC, e os valores se mantiveram estáveis ou com aumentos pouco expressivos em SCB. A adição de cimento fez com que a capacidade de troca catiônica das misturas se reduzisse, no entanto, tornou-as alcalinas, favorecendo a precipitação do Cu2+. Ao contrário dos CCL que tem a sorção como principal mecanismo de retenção de contaminantes, nas misturas SCC e SCB é a precipitação, para o caso de elementos sensíveis a mudanças de pH como o Cu2+. Isso foi observado pelos precipitados formados durante os ensaios de coluna e no batch test, pela demora para saída de Cu2+ nos efluentes do ensaio de coluna e pelos valores de Rd obtidos em ambos os ensaios para SCC e SCB. Como as duas misturas apresentaram desempenhos similares, nota-se que as características mineralógicas dos materiais argilosos tiveram pouca influência no desempenho de K e Rd das misturas, provavelmente relacionado aos efeitos expressivos do cimento para redução de K e ao favorecer a precipitação do Cu2+. Quando comparadas as barreiras de CCL e aos geocompostos bentoníticos, as misturas SCC e SCB apresentaram desempenhos similares e, por vezes, mais elevados quanto ao Rd, apesar de apresentar valores de K mais altos, mas que ainda assim atendem a norma. Logo, as misturas solo-cimento-argila mostrou ser uma alternativa com bom desempenho para aplicação de solos arenosos como barreiras de baixa permeabilidade. Potentially toxic metals are non-biodegradable elements that are easily absorbed by organisms and have a high bioaccumulation capacity and are also present in the slurry of landfills. Because of this, the low permeability barriers in these structures are fundamental elements for environmental protection. These liners are commonly made from compacted clayey soils (CCL) because they meet the requirements of hydraulic conductivity (K) and retention of contaminants. In the absence of clayey soils, the use of sandy soils for this application is of great interest. Therefore, the present research aimed to apply an improvement technique to a sandy soil, adding cement and clay, to evaluate the aspects of K and the retardation factor (Rd) of contaminants in the soil-cement-kaolin (SCC) and soil-cement-bentonite (SCB). For this, the following tests were performed: physical, physico-chemical and mineralogical characterization of soil, clay materials and soil-cement-clay mixtures; column assay to evaluate K with the percolation of water and CuCl2.2H2O solution (0.012M and 0.024M) and Rd of Cu2+; and the batch test at concentrations of 0.005M, 0.012M and 0.024M were used to evaluate the Rd obtained and compare with Rd of the column assay. When evaluating K with water percolation, it was observed that if the moisture content applied is above the optimum humidity of the mixture, the compaction efficiency is compromised and causes the K values to be higher. SCB mixtures and SCC met the standard K requirements for application as background liners in sanitary landfills with a mean value of 3.7x10-10 and 5x10-10 m/s, respectively. During percolation of the contaminant solution, there was reduction of K in SCC, and the values remained stable or with a little expressive increases in SCB. The addition of cement caused the reduction of cation exchange capacity of the mixtures, however, made them alkaline, favouring the precipitation of Cu2+. Unlike the CCL, that has the sorption as the main mechanism of retention of contaminants, in the SCC and SCB mixtures is the precipitation, in the case of elements sensitive to changes of pH, like Cu2+. This was observed by the precipitates formed during the column tests and the batch test, the delay for Cu2+ exit in the column assay effluents and the Rd values obtained in both SCC and SCB tests. As the two mixtures presented similar performances, it isnoted that the mineralogical characteristics of the clayey materials had little influence on the K and Rd performance of the mixtures, probably related to the expressive effects of the cement for K reduction and favouring the precipitation of Cu2+. When CCL liners and bentonite geocompounds were compared with SCC and SCB mixtures, the soil-cement-clay mixtures showed similar and sometimes even higher performances for Rd, despite having higher K values than these but still meeting the standard. Therefore, soil-cement-clay mixtures showed to be a good performance alternative for the application of sandy soils as low permeability liners.

A presença de encostas com solos na condição não saturada é muito comum na região Sudeste brasileira devida às características climáticas e hidrogeológicas regional. Neste caso, o mecanismo de instabilização pode ser basicamente descrito pela redução da coesão aparente provocada pela infiltração da água da chuva, causada pela diminuição ou até mesmo a anulação dos efeitos da sucção matricial, tornando o talude instável. O presente trabalho apresenta um estudo dos mecanismos instabilizadores em um talude de corte composto por solo residual arenoso localizado na Rodovia Luis Augusto de Oliveira (SP-215) no km 179+300 LE, próximo ao município de Ribeirão Bonito, Brasil. Neste trabalho foi realizado um levantamento dos dados e das propriedades do solo (física, mecânica e hidráulica) da área piloto utilizando métodos de investigação geológico-geotécnica de superfície (levantamento topográfico de detalhe, caminhamentos) e de subsuperfície (sondagem a trado e poços com coleta de amostras); ensaios de laboratório e de campo (índices físicos do solo, resistência ao cisalhamento, permeabilidade); instrumentação e monitoramento (piezômetro, pluviômetro e tensiômetro) e modelagem numérica (análises da infiltração da água da chuva e de estabilidade de talude). Na área investigada ocorrem solos residuais dos arenitos eólicos da Formação Botucatu (Grupo São Bento, Bacia Sedimentar do Paraná) de idade jurássico-cretácea. As modelagens numéricas realizadas no programa GeoStudio versão 2012 (Seep/W e Slope/W) confirmaram que é possível ocorrer deslizamentos rasos de solo somente pela redução da sucção e perda de coesão aparente. As modelagens do fluxo da água infiltrada no talude apresentaram resultados divergentes das leituras registradas pelos tensiômetros instalados no talude monitorado e os fatores de segurança mostraram serem bem superiores ao unitário, mesmo ocorrendo chuvas de alta intensidade pluviométrica. Estas modelagens numéricas também permitiram estabelecer a configuração geométrica crítica (altura e inclinação) para os taludes de corte em solo residual arenoso da Formação Botucatu. The presence of slopes with soil in the unsaturated condition is very common in Brazil\'s Southeast region due to climate and regional hydrogeological characteristics. In this case, the instability mechanism can be basically described by the apparent cohesion loss caused by the rainfall infiltration that induced by the reduction or even annulling the effect of matric suction, making the slope conditionally unstable. This paper presents a study of instabilizing mechanisms in a cut slope composed of sandy residual soil located on Highway Luis Augusto de Oliveira (SP-215) at km 179 + 300 LE, near Ribeirão Bonito, Brazil. This work was carried out a survey of the data and soil properties (physical, mechanical and hydraulic) of pilot area using geological and geotechnical research techniques of surface (topographic survey) and subsurface (soil sampling and hand auger drilling); laboratory and field tests (physical indices soil, shear strength, permeability); instrumentation and monitoring (piezometer, rain gauge and tensiometer) and numerical modelling (analysis of rainfall infiltration and slope stability). In the investigated area occur residual soils of aeolian sandstones of Botucatu Formation (São Bento Group, Paraná Sedimentary Basin) Jurassic- Cretaceous age. The numerical modelling performed in GeoStudio version 2012 (Seep/W and Slope/W) confirmed that it is possible to have shallow soil slips just reducing the suction loss and apparent cohesion. The modelling of the infiltrated water flow on the slope showed conflicting results of the readings recorded by tensiometers installed on the monitored slope and the safety factors shown to be well above the unit, even occurring high intensity rainfall. These numerical models also allowed to establish the geometric critical configuration (height and slope angle) for cut slopes in a sandy residual soil of Botucatu Formation.

A decomposição de resíduos sólidos urbanos em aterros sanitários é uma fonte importante de metano para a atmosfera. Este gás tem uma contribuição significativamente maior que o dióxido de carbono na retenção do calor na atmosfera e no consequente aquecimento global (efeito estufa). A oxidação biológica do metano nos sistemas de cobertura de aterros é uma alternativa para a diminuição das emissões fugitivas deste gás. Esse processo ocorre pela atividade microbiana em ambientes nos quais estão disponíveis metano, oxigênio e bactérias metanotróficas. O potencial de oxidação de metano nas camadas de cobertura de aterros de resíduos sólidos urbanos (RSU) pode ser favorecido pela criação de condições ambientais propícias. Este trabalho propõe uma metodologia para monitoramento e quantificação da oxidação do metano, a fim de avaliar o desempenho de diferentes materiais para coberturas oxidativas, levando-se em conta os aspectos climáticos. Foram avaliados dois sistemas de coberturas por meio de biofiltros. Estes biofiltros foram instalados no aterro DELTA A da cidade de Campinas, utilizando como fonte de metano um poço de captação de biogás do aterro. Foram utilizados dois tipos de materiais, um com resíduo de construção e demolição (RCD) e outro com areia natural, os dois misturados a composto orgânico maduro. Foram monitorados ao longo de 20 meses os perfis de concentração dos gases (metano, dióxido de carbono e oxigênio) e os fatores meteorológicos (pressão atmosférica, temperatura e precipitação). O estudo demonstrou que as duas misturas utilizadas podem oxidar o metano e que o fluxo de metano é controlado pela permeabilidade ao gás e este fluxo condiciona o percentual de oxidação. O valor máximo de oxidação obtido foi de cerca de 10 kg de CH4/m²dia. O estudo propõe, ainda, uma metodologia para quantificação da oxidação do metano que toma como base as medições de concentração ao longo do perfil da camada e a vazão oxidada. The decomposition of solid waste in landfills is a major source of methane to the atmosphere. This gas contributes more than carbon dioxide to heat trapping in the atmosphere and to the consequent global warming (greenhouse effect). The biological oxidation of methane in landfill cover systems is an alternative to reduce fugitive gas emissions. This process occurs by microbial activity in environments where methane, oxygen and methanotrophic bacteria are available. The methane oxidation in urban landfill cover systems can be improved by the creation of favorable environment conditions. A methodology for monitoring and quantification of methane oxidation is proposed, to evaluate the performance of different materials for oxidative cover, taking into account the climatic aspects. We evaluated two biofilter cover systems installed at Delta A landfill located in the city of Campinas (SP). The gas collection system well was used as methane source. Two different materials were tested: (1) construction and demolition waste and (2) natural quartz sand, both mixed with organic mature compost. The methane, carbon dioxide and oxygen concentration profiles and meteorological factors (atmospheric pressure, temperature and precipitation) were monitored over 20 months. The two materials were capable of oxidizing methane. Methane oxidation was affected by flow rate through the cover system, and therefore by the material gas permeability. The maximum methane oxidation rate was approximately 10 kg CH4/m².day. A methodology is proposed for quantifying methane oxidation based on measurements of methane concentration and flow rate in the upper part of the biofilter.

Este trabalho apresenta a caracterização in situ de propriedades de interesse geotécnico de maciços de resíduos sólidos urbanos (RSU) e o estudo das propriedades de resistência ao cisalhamento de RSU com diferentes idades. Foram realizadas investigações por sondagens e com métodos geofísicos sísmicos no Aterro Sanitário de São Carlos (ASSC) e ensaios de cisalhamento direto de grandes dimensões (50x50 cm2) com amostras de diferentes idades de aterramento coletadas no ASSC, no Lixão Desativado de São Carlos e em Aterro Experimental construído nas proximidades do Lixão. As investigações realizadas no ASSC revelaram que as diferentes fases de operação do maciço (aterro controlado e aterro sanitário) produziram dois estratos com diferentes propriedades geotécnicas. A umidade, as velocidades de propagação de ondas sísmicas e o peso específico in situ dos dois estratos são distintos, sendo sempre menores e menos dispersos no estrato mais raso (operado como aterro sanitário) e maiores e mais dispersos no estrato mais profundo (operado como aterro controlado). Realizaram-se tentativas de determinação do peso específico in situ dos RSU com medição dos volumes escavados por substituição de volume. Notou-se que os furos tendiam a diminuir de diâmetro assim que a composição de sondagem era retirada e que o método adotado para avanço dos furos, com trado helicoidal de haste oca, promovia segregação dos componentes atravessados, realizando uma amostragem parcial dos mesmos. Foram calculados valores médios de peso específico in situ para o maciço investigado (9 a 15 kN/m3) e identificadas as principais limitações da aplicação deste método a aterros sanitários. A aplicação de métodos geofísicos sísmicos foi fundamental para a diferenciação dos dois estratos e permitiu que se calculasse o módulo de cisalhamento máximo (Go) dos resíduos, que variou significativamente de um estrato para outro. Foi possível comparar os resultados obtidos com a aplicação do método crosshole e do método multichannel analysis of surface waves (MASW) no mesmo aterro sanitário. A caracterização das seis amostras utilizadas nos ensaios de cisalhamento direto revelou que, apesar de elas representarem idades distintas de disposição dos resíduos (2 a 25 anos) e condições de aterramento variadas (formas de operação dos depósitos, ambientes de decomposição e condições de confinamento), a maioria delas se encontrava em estágio avançado de degradação (fase metanogênica) e apenas a mais recente (2 anos de aterramento) encontrava-se em estágio um pouco menos avançado de degradação (início da fase metanogênica). Todas elas exibiram curvas tensão-deslocamento semelhantes, sem pico ou valor de máxima resistência bem caracterizados. Os parâmetros de resistência ao cisalhamento foram obtidos a partir de níveis específicos de deslocamento. Avaliou-se a influência da amostragem, dos procedimentos de preparação das amostras e da composição gravimétrica de cada uma delas sobre os valores calculados para coesão e ângulo de atrito. Para deslocamentos de 100 mm o resíduo aterrado há dois anos apresentou coesão de 13,7 kPa e ângulo de atrito de 22º. Os resíduos mais degradados, com idades de disposição entre 5 e 25 anos, apresentaram coesão de 4,4 kPa e ângulo de atrito de 30º. Utilizaram-se tensões normais de 50, 150 e 250 kPa. Realizaram-se ainda ensaios de cisalhamento direto de grandes dimensões em uma das amostras com corpos de prova em duas posições: paralela e perpendicular à direção de compactação. Os resultados confirmaram que os RSU têm comportamento anisotrópico, sendo que os corpos de prova ensaiados com os componentes alinhados preferencialmente na posição vertical (rotacionados) têm comportamento de endurecimento ainda mais pronunciado que aqueles ensaiados com os componentes orientados preferencialmente no plano horizontal. Field and laboratory tests were combined to characterize some in-place geotechnical properties of the waste body in the São Carlos Sanitary Landfill (SCSL). The investigation was carried out using hollow stem auger soundings and seismic geophysical methods in the field, and large-scale direct shear testing in the laboratory. The field investigation revealed two strata with different geotechnical properties and they could be related to the different operational phases of the landfill (controlled landfill and sanitary landfill). Moisture content, seismic wave velocities and in-place unit weight were systematically lower and less scattered in the upper stratum than in the lower stratum. The upper stratum was operated as a sanitary landfill and the lower stratum was operated as a controlled landfill. The investigations with geophysical seismic methods were essential for identifying the two strata and allowed for the calculation of the Poisson ratio and the small strain shear modulus (Go) of the waste body. The Poisson ratio showed no sensibility to the waste stratigraphy, but Go values were significantly higher in the lower stratum. Moreover, the results of two different geophysical methods, namely crosshole and multichannel analysis of surface waves (MASW), could be compared. An attempt was made to estimate overboring using a volume substitution method by filling the boreholes with gravel. This aimed at incorporating this aspect in the calculations of the MSW in-place unit weight. Nevertheless, the borings tended to cave in as soon as the augers were removed and this prevented the evaluation of the overboring. Moreover, the hollow stem auger tended to segregate the larger components of the waste and to bring only the smaller ones to the surface. Despite all these difficulties, average values for the MSW inplace unit weight were be calculated (9 to 15 kN/m3). In the laboratory, large-scale direct shear tests (500 x 500 mm2) were performed to provide an insight on the shear strength response of municipal solid waste (MSW) of different landfilling ages. The test samples were collected from the SCSL, a dumpsite and an experimental landfill. Their landfilling ages ranged from 2 to 25 years. Physico-chemical characterization of the samples revealed that most of them were subjected to the metanogenesis degradation phase, in spite of their different landfilling ages and burial conditions (operational characteristics of the deposits, decomposition environment and confining pressures). Only the newest one (2 years old sample) was subjected to an earlier stage of degradation. In the direct shear tests, all samples showed similar stress-strain curves, with continuous strain hardening and no identifiable maximum stress, despite the large displacements. The influence of sampling method, sample preparation and sample gravimetric composition on the calculated shear resistance parameters is discussed. For a 100-mm displacement the shear resistance of the less degraded waste (2 years of landfilling) is best characterized by cohesion = 13.7 kPa and friction angle = 22º. The more degraded wastes (5 to 25 years old samples) are best characterized by cohesion = 4.4 kPa and friction angle = 30º. The tests were performed with initial normal stresses of 50, 150 and 250 kPa. Specific large direct shear tests were performed to evaluate anisotropy in the MSW shear response. The test samples had the fibrous materials oriented perpendicular or parallel to the horizontal shear surface. Results confirmed the expected anisotropy by showing a hardening behaviour that was more pronounced when the fibrous materials were oriented perpendicular to the shear plan.

A função condutividade hidráulica é um dos parâmetros essenciais para o estudo do fluxo em solos não saturados, permitindo abordar, dentre outros, o avanço da frente de umedecimento e questões como a irrigação e drenagem de solos. Para determinar a condutividade hidráulica não saturada de um solo típico da região Centro-Oeste do Estado de São Paulo, utilizou-se o infiltrômetro de disco. Este equipamento permite conduzir a infiltração de água, estando esta sujeita a um potencial negativo. Com os dados de infiltração acumulada e tempo acumulado obtidos em cada ensaio, foi possível determinar os valores da condutividade hidráulica não saturada e sortividade. Os cálculos foram feitos por diferentes métodos para cada ensaio realizado com o infiltrômetro de disco e comparadas com resultados de ensaios utilizando o permeâmetro Guelph. Observou-se que as condutividades hidráulica não saturadas obtidas com o infiltrômetro de disco tenderam a valores próximos das fornecidas indiretamente por meio do permeâmetro Guelph, com dispersão de aproximadamente uma ordem de grandeza para cada sucção. Também se observou que a condutividade hidráulica não saturada tende a diminuir conforme aumenta a sucção imposta ao solo, mesmo considerando a estreita faixa de sucções usadas nos ensaios. Notou-se ainda pequena variação nas condutividades hidráulicas saturadas calculadas por meio do infiltrômetro de disco, por meio de medidas diretas utilizando o permeâmetro Guelph e ensaios de permeabilidade realizados em laboratório. The hydraulic conductivity function is essential to the study of water flow in unsaturated soils. From function there can be derived the advancement of the humidification (saturation) front, among other parameters, which is essential to projects of irrigation and drainage of soils. A disk infiltrometer was used to determine the unsaturated hydraulic conductivity of a sample of typical soil from central São Paulo, Brazil. The disk infiltrometer apparatus conducts the infiltration water, which is held at negative potential. Data for cumulative infiltration and elapsed time for each test was used to determine values of unsaturated hydraulic conductivity and sorptivity. Different methodology was applied in the calculations. Data for each experiment carried out utilizing the disk infiltrometer was compared to data obtained utilizing the permeameter of Guelph. It was observed that the unsaturated hydraulic conductivity obtained through the disk infiltrometer yielded values near those obtained indirectly by the permeameter of Guelph, which showed dispersion approximately within one order of magnitude for each suctioning performed. Furthermore, it was observed that the unsaturated hydraulic conductivity tends to diminish in magnitude in an inverse relation to the suction pressure subjected by the soil, even after considering the narrow band of suction pressures carried out in the tests. It was further observed a small variation in the saturated hydraulic conductivities computed from data obtained directly from the infiltrometer disk, the permeameter of Guelph, and other permeability tests done in laboratory.

The concern with urban planning and the rational search for new areas for urban expansion, with positive indicators, has been more looking for nowadays. This happens because the sustainability policy demand a appropriate interaction between man and the environment; the environmental impacts and their agents can change to review and have attracted interests around the world in the search of solutions, enabling the coexistence of man with environment. This is due in the requirement of studies and research about the structure and dynamics of the environment and your potentiality and or vulnerability in relation of introduction of news activities, even in not planned cities. At this point, the study and the use of System of Geographic Information - SGI combined with geotechnical investigation can mean progresses in the right occupation of urban areas, in priority areas, especially when is in front of historic of occupation of the Sarandi city, Paraná. On this hand, based on the study aims that is to draw a map of environmental erodibility, was developed and systematized a map of environmental vulnerability on Mauá Basin Creek, on the city of Sarandi, which is considered an area of urban expansion. Using the Nakashima (1999) methodology to the systematization of the work and using the methodology proposed by Crepani et al. (2001) to development of vulnerability map, both of them with some modifications. On this way, realized that for the Mauá Basin Creek, Sarandi/PR, the map of environmental vulnerability is an important tool for a urban and rural planning, in order to guide the urban expansion on new areas, allowing, according to the environmental preservation, the ration and proper user for a management of areas unfavorable to certain types of use land and soil. A preocupação com o planejamento urbano e com o estabelecimento racional de novas áreas para expansão urbana vem tomando lugar nas decisões dos gestores públicos. Isto se deve à política da sustentabilidade que busca o convívio adequado do homem com o meio, pois os impactos ambientais e os seus agentes transformadores podem conduzir a passivos que demandam remediações nem sempre economicamente viáveis. Neste sentido é crescente a necessidade de estudos e pesquisas sobre a estrutura e a dinâmica do meio e a sua potencialidade e ou vulnerabilidade em face da introdução de novas atividades, mesmo em cidades que foram ou não planejadas. A utilização do Sistema de Informação Geográfica - SIG, aliado a levantamentos geotécnicos em estudos de avanço e da ocupação correta de áreas urbanas, tem-se constituído em uma ferramenta útil e necessária, como foi observado no caso do Município de Sarandi - Paraná. Neste sentido, tomando como base o objetivo geral que é o de elaborar um mapa de vulnerabilidade ambiental, foi realizado e sistematizado um mapa de vulnerabilidade ambiental da Bacia do Córrego Mauá, do município de Sarandi, considerada como área de expansão urbana. Na sistematização dos trabalhos foi adotada a metodologia de Nakashima (1999) enquanto que na elaboração do mapa de vulnerabilidade foi adotado a metodologia proposta por Crepani et al. (2001), ambos com algumas modificações. Desta forma, verificou-se que, para a Bacia do Córrego Mauá, Sarandi/PR, o mapa de vulnerabilidade ambiental se constituiu em uma importante ferramenta de planejamento urbano e rural, no sentido de orientar a expansão urbana em novas áreas, possibilitando em vista da preservação ambiental o uso racional e o correto manejo de áreas no que se refere ao uso e ocupação do solo. xiv, 156 f

Na região de Londrina, as estacas do tipo Strauss são muito utilizadas em obras de edificações como contenções de escavações de subsolos, no entanto, os projetos dessas contenções normalmente são realizados utilizando métodos de dimensionamento que não levam em consideração a fissuração do concreto do fuste da estaca e as propriedades do solo tropical laterítico, típico da região. Neste trabalho foi estudado o comportamento de estacas Strauss sob esforço horizontal através da análise de provas de carga estática realizadas no Campo Experimental de Engenharia Geotécnica (CEEG) da UEL. As nove estacas Strauss ensaiadas possuíam diâmetro de 32 cm e 12 metros de comprimento, sendo seis armadas por 3 barras de aço de 8 mm e três armadas por 7 barras de aço 8 mm, em toda sua extensão. O CEEG apresenta um perfil geológico-geotécnico típico da região de Londrina, constituído por solo residual de basalto, cuja camada superficial de solo argilo-siltoso é porosa e colapsível além de possuir origem e comportamento lateríticos, ou seja, apresenta um comportamento geotécnico em campo semelhante às areias, apesar de possuir quase 80% de argila em sua composição granulométrica. As provas de carga foram conduzidas aos pares, e os resultados obtidos são apresentados através das curvas carga x deslocamento horizontal do solo em duas condições: não-saturado e com pré-inundação por 36 e 12 horas. Com o solo no estado não-saturado, as estacas com menor rigidez estrutural apresentaram uma carga de ruptura média de 20 kN, enquanto que, as de maior rigidez, a ruptura ocorreu com 30 kN. Já as cargas de colapso para os dois tipos de estacas foram de 15 kN e 27 kN, para tempos de pré-inundação de 36 e 12 horas, respectivamente. Os métodos de Gabr & Borden (1989) e Robertson et al. (1989) foram utilizados a fim de verificar a concordância das curvas p-y geradas. Verificou-se que o primeiro método apresenta boa concordância com os resultados obtidos em campo e, o segundo método, através expressão especifica para solos não-coesivos, somente apresentou bons resultados após a alteração do fator de correção Fs. A partir dos resultados das provas de carga, foi obtido um coeficiente nh médio do solo de 5 MN/m³, muito próximo ao obtido por outros trabalhos no mesmo campo experimental. Observou-se que, devido à consideração da fissuração do concreto na carga de ruptura das estacas, houve um acréscimo médio de 39% nos deslocamentos para as estacas compostas por 3 barras de aço e 28% para as estacas com 7 barras de aço, na superfície do terreno. In Londrina city, Strauss piles are frequently used as retaining structure for building basement excavation, being submitted to horizontal load. However, the projects of such retaining structures are usually conducted using design methods that do not take the concrete cracking of pile transversal section and the properties of lateritic tropical soil into account. This work aimed to study the behavior of Strauss piles under horizontal loads by means of horizontal bearing capacity tests, carried out on Geotechnical Experimental Site (CEEG) of Londrina State University. Nine Strauss piles were tested. They were 12 meters long and had 32 cm in diameter. Six piles were reinforced with three steel bars and three piles were reinforced with seven steel bars, along their entire lengths. The geotechnical profile of experimental field is typical of Londrina city and can be defined as a basaltic residual soil, with a superficial layer of a porous and collapsible silty-clay soil. This soil presents a lateritic behavior, what means that its geotechnical field behavior is similar to a sandy soil, despite the fact that it has almost 80% of clay grains. The horizontal load tests results were performed on two piles at each same time, and the results were presented in load x horizontal displacement curves under two soil conditions: non-saturated and pre-wetted during 36 and 12 hours. Under no wetted moisture conditions, the less structural rigid piles presented an average horizontal bearing capacity of 20 kN, whereas that, for the most rigid piles, the rupture occurred with 30 kN of horizontal load. The collapse loads for the two pile types were 15 kN and 27 kN, to the pre-flood times of 36 and 12 hours, respectively. The Gabr & Borden (1989) and Robertson et al. (1989) methods were used to check the correlation between experimental and computed the p-y curves. It was found that the first method gives good agreement with the results obtained in field, and the second method, using expression for non-cohesive soils, only showed good results if a correction in Fs factor is considered. From the horizontal load tests results, it was found an average soil coefficient, nh, equal to 5 MN/m³, that is very close to that achieved by other researches in the same experimental site. Due the consideration of concrete cracking for the rupture loads of piles, it was observed an increase in average displacements of 39% for piles reinforced with 3 steel bars and 28% for piles with 7 steel bars, at the ground surface.

O presente estudo teve como objetivo não só o do mapeamento dos parâmetros geotécnicos de resistência à penetração do amostrador-padrão e de Torque Máximo do SPT-T (Standard Penetration Test with Torque Measurement), obtidos a partir de um banco de 238 sondagens realizadas na bacia hidrográfica do ribeirão Cambezinho, que compreende parte da zona urbana da cidade de Londrina/Pr, mas também de correlacionar estas variáveis qualitativamente a fatores tais como a topografia e pedologia. A área em estudo foi de aproximadamente 37 Km². O perfil de solo da área de estudo se constitui de argila siltosa residual, proveniente do intemperismo atuante sobre as rochas basálticas da Formação Serra Geral. A camada de solo superficial possui alta porosidade e comportamentos laterítico e colapsível. Através de ferramentas da estatística descritiva e da estatística espacial, procederam-se a análise, a interpolação e a interpretação dos resultados das sondagens no que se refere ao Torque Máximo e ao NSPT. Estes resultados foram geoprocessados e analisados juntamente com os fatores naturais anteriormente descritos através de mapas topográficos e pedológicos. A principio, para a área urbana da bacia do ribeirão Cambezinho, não se detectou nenhuma correlação entre os índices de resistência do solo medidos no SPT-T e a pedologia ou topografia. Percebeu-se porém que o comportamento espacial da relação dos índices de resistência medidos no SPT-T, NSPT e Torque Máximo, é semelhante ao observado na análise de sondagens isoladas, ou seja, resguardam uma proporção de aproximadamente 1, e que quanto maior o grau de intemperização sofrido pelo solo menor é à resistência que o mesmo apresenta. This study has as its objective to map the resistance geotechnical parameters of NSPT and Maximum Torque, obtained from a data bank of 238 field tests of SPT-T (Standard Penetration Test with Torque Measurement) done in the Cambezinho hydrographic creek basin, that comprehends part of urban zone of the city of Londrina/Pr and to correlate these variables to factors as topography and pedology. The experimental area has approximately 37 km². The geotechnical profile of the experimental area consists in a residual silty clay that originates from the intemperism acting on the basaltic rocks of the Serra Geral Formation. The superficial layer has a high porosity and lateritic and collapsible behavior. Through descriptive and spatial statistics tools were done the analysis, interpolation and the interpretation of the results of the field tests about the Maximum Torque and NSPT measured. Then, the results were geoprocessed and analyzed along with the natural factors explained above through altimetric and pedologic maps. In an early analyses, it was not realized any relation among the SPT-T parameters and the pedology or topography, inside the urban zone of the Cambezinho creek basin. However, it was realized that the spacial behavior of the relation between the resistance parameters measured in the SPT-T ,NSPT and Maximum Torque, is the same as observed in the analyses of isolated tests field, which means that they are approximately equal, and as the bigger is the intemperization level that the soil has suffered the smaller is the resistance it reaches.

Este trabalho apresenta a avaliação dos efeitos da estabilização química com cal e cimento na condutividade hidráulica e resistência à compressão de um solo arenoso proveniente da Formação Botucatu (Estado de São Paulo, Brasil), com o objetivo de obter um material menos permeável e mais resistente. O projeto e análise de experimentos foram realizados através de um planejamento fatorial 3², com duas variáveis independentes: teor de umidade e porcentagem de estabilizante, variando em três níveis cada. Foi utilizado cal hidratada CH-III, cimento Portland CP II-Z32 e água fornecida pela concessionária local. Os ensaios de condutividade hidráulica (K) foram executados em permeâmetros de carga constante. Foram realizados ensaios de resistência a compressão simples (RC) após 7 e 28 dias de cura. As amostras de solo estabilizado e natural foram compactadas na energia Proctor Normal. Na avaliação da estrutura das amostras de solo estabilizado verificou-se a alteração da matriz de poros promovida pela adição de cal e cimento. Após a obtenção dos resultados, análises estatísticas possibilitaram avaliar os efeitos das variáveis independentes sobre o K e RC. Pelo método de superfície de respostas foi possível demonstrar o comportamento das misturas e identificar a tendência de alteração das propriedades. As amostras de solo-cimento alcançaram reduções de condutividade hidráulica de até 9,5 x 10-7 m/s e o menor valor experimental de K foi de 1,4 x 10-8 m/s. Os ensaios de RC, com 28 dias de cura, apresentaram acréscimo de resistência de até 5,1 MPa e os resultados obtidos possuem uma variação, aproximadamente, entre 0,1 e 5,1 MPa. O procedimento adotado permitiu avaliar a influência dos fatores e determinar as misturas ótimas para cada estabilizante. A laboratory study was conducted to evaluate the effects of lime and cement stabilization over the hydraulic conductivity and unconfined compressive strength of a sandy soil from Botucatu Formation (São Paulo State, Brazil) with the intend to generate a less permeable and more resistant material. The experiment was performed using the technique of factorial design 3², with the two independent variables: moisture content and stabilizer percentage, varying on three levels each. Hydraulic conductivity (K) was measured in constant-head permeameters. Unconfined compressive strength (CS) was measured after 7 and 28 days of curing. The samples of stabilized and natural soils were compacted with the normal Proctor energy. The evaluation of the stabilized soil structure verified a pore matrix modification promoted by lime and cement addition. With the results of the characterization, statistical analysis allowed to assess the effects of the variable factors on K and CS. The response surface method was used to demonstrate the hydraulic and compressive strength behavior of the stabilized soil. The soil-cement hydraulic conductivity achieved reductions up to 9.5 x 10-7 m/s and the lowest K experimental value was 1.4 x 10-8 m/s. The compressive strength, with 28 days of curing, presented an increase in CS up to 5.1 MPa and the obtained results showed a range between 0.1 and 5.1 MPa. The adopted experimental procedure allows the assessment of the variables influence and the determination of the optimal mixtures for each stabilizer.