R E S U M OCoagulantes naturais e sistemas de filtração são tecnologias de tratamento de água, indicadas para comunidades rurais ou isoladas. Este estudo objetivou comparar duas formas de aplicação de coagulante extraído de sementes de Moringa oleifera. Utilizaramse o coagulante líquido (10 mL L -1 a 20 g L -1) e sachê contendo 0,8 g de pó de sementes de Moringa oleifera. Após as etapas de dispersão da proteína presente nas sementes de Moringa oleifera, coagulação e floculação efetuaram-se pré-filtração ascendente e filtração lenta. Diferenças significativas foram observadas entre o uso do coagulante líquido e sachê na redução de turbidez e cor aparente. Com o uso dos sachês o pré-filtro foi menos eficiente notando-se reduções médias de turbidez igual 73 e 83% para os sachês e coagulante líquido, respectivamente. No filtro lento verificou-se redução média de 84 e 60% com o uso de sachês e coagulante líquido, respectivamente. Considerando todo o sistema de filtração, o uso dos sachês resultou em elevados percentuais de redução de turbidez e cor aparente; além de que seu preparo não requer o uso de água, condição que favorece sua aplicação em regiões em que há escassez de água com qualidade. Different forms of application of Moringa oleifera seeds in water treatmentA B S T R A C T Natural coagulants and filtration systems are suitable water treatment technologies in rural or isolated communities. This research aimed to compare two forms of application of coagulant extracted from Moringa oleifera seeds. Coagulant liquid (10 mL L -1 at 2%) and pouches containing 0.8 g powder were used. The dispersion, coagulation and flocculation steps were performed prior to both up flow gravel pre-filtration and slow sand filtration. Significant differences were observed for the liquid coagulant and pouches regarding the reduction of turbidity and apparent color. Although the up flow gravel pre-filter was less effective with the use of pouches, with an average reduction of turbidity of 73.5 and 82.5% for the pouches and liquid coagulant, respectively, the effluent of the slow filter presented lower turbidity, with an average reduction of 83.9 and 60.1% for the pouches and liquid coagulant, respectively. Considering the filtration system (up flow gravel pre-filter and slow sand filter) the use of pouches showed high reduction of turbidity and apparent color. The preparation of pouches does not require the use of water, a condition that favors its application in areas with lack of water of acceptable quality. Palavras-chave:saneamento rural coagulante natural filtração lenta

Concrete is one of the oldest building materials known to humankind. From 1824, with the advent of Portland cement, concrete assumed a prominent place among the construction materials, due to large amounts of strength, durability and versatility it offered compared to other products, allowing the molding of various forms architectural. Until the early 80s, the concrete remained only as a mixture of cement, aggregates and water, however, in recent decades, due to the development of new techniques and products, the concrete has been undergoing constant changes. The concrete with lightweight aggregates have been used since the beginning of the last century, with low values of density (< 2000 kg/m3), demonstrating the great potential of using this material in several areas of construction [. With the objective of analyzing the influence of the consumption of cement in conventional concrete and light, were molded, tested and compared body-of-evidence containing two different amounts of cement consumption: a) 350 kg/m3 and b) 450 kg / m3. The results were compared with those obtained by other researchers, as well as with [ and [.

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Concrete is one of the oldest building materials and applying known to humankind. From 1800s, with the advent of Portland cement concrete has taken a prominent place among the construction materials due to large values of strength, durability and versatility it offered compared to other products, allowing the molding of the various architectural forms. Until the early 80s, the modern concrete remained only as a mixture of cement, aggregates and water, however, in recent decades, due to the development of new techniques and products, the concrete has been undergoing constant changes [. This article discusses the application of technology of lightweight aggregates for concrete production, for use in building elements such as structural panels or fence. Developed an experimental program for the analysis of concrete, with the primary objective to characterize the properties of the parts in the hardened state. The results showed that the lightweight aggregate concrete with Brazilian expanded clay are extremely suitable for the production of prefabricated elements slender, mainly due to the reduction in density and excellent performance in mechanical properties, especially modulus of elasticity, despite the low toughness of lightweight aggregate.

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Este artigo apresenta uma análise numérica de solos não saturados colapsíveis, utilizados em uma pequena barragem de terra localizada no município de Quixadá, Estado do Ceará, Brasil. A estrutura colapsível foi resultado da aplicação de baixa energia de compactação e baixa umidade. São apresentados resultados dos ensaios de caracterização, compactação e adensamento duplo para o material oriundo da jazida empregada na construção da pequena barragem, com o objetivo de identificar as amostras analisadas e estudar o fenômeno do colapso. Através dos resultados dos ensaios, foi realizada uma análise numérica de fluxo e equilíbrio, com os programas Slide 6.0 e UNSTRUCT, de forma associada, para previsão do comportamento tensão x deformação (colapso) da barragem experimental. A seção transversal da barragem é constituída de núcleo com material compactado na umidade ótima e energia de Proctor Normal, e de espaldares no ramo seco. O objetivo é verificar a eficiência do maciço construído com redução de custos (por diminuição de terraplenagem) e redução do consumo de água, tornando-a uma importante solução construtiva para pequenas barragens em regiões semiáridas. Os estudos experimentais e numéricos da obra com estas características apontaram condições de estabilidade, tendo em vista que a barragem não apresentou ruptura durante o monitoramento.

Since the invention of modern concrete, in the mid-nineteenth century until the early 80s, the concrete remained a mixture of aggregate, cement and water, with no major innovations that significantly alter the performance of its properties. But in recent decades, concrete technology has undergone tremendous development that has occurred due to the development of techniques and equipment for the study of the concrete and the use of new materials.The concrete with lightweight aggregate have been used, mainly due to the low values of density, thus demonstrating the great potential of using this material in several areas of construction [.With the objective of analyzing the influence of the consumption of cement in conventional concrete and light, were molded, tested and compared body-of-evidence containing two different values of cement consumption. The values were compared with those obtained by other researchers, as well as with the ABNT NBR 6118:2003 [ and ACI 213R-03:2003 [.

This study aims to address the question of accessibility on sidewalks in accordance with Rule 9050 of the Brazilian Association of Technical Standards (ABNT NBR 9050:2004) and analyze the feasibility of using alternative materials (steel fibers, construction waste and rubber) to produce Interlocking tactile concrete paver. It was performed an experimental dosage of concrete with 04 specimens: reference, with steel fiber, with rubber and with steel fiber and construction waste. The pavers molded with conventional concrete and with the addition of alternative materials were tested as for compression strength and water absorption and the results were satisfactory, meeting the specifications of the Brazilian standard.