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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

C-beam environmental roof

Chalatse, Keketso E January 2003 (has links)
Thesis (MTech (Civil Engineering))--Cape Technikon, Cape Town, 2003 / South Africa is experiencing great movements of people from rural areas to towns mainly because of the need to find work. Accommodation is limited and expensive, forcing many to live in informal homes. The municipalities, in an attempt to accommodate as much as they can, provide small plots, which basically can only accommodate a house and a very small garden. This country like other countries of the world has also embarked on numerous low-cost housing schemes to accommodate the homeless. Because of economic realities and because high-rise options are not considered acceptable, the most practical solution has resulted in large-scale low-density urban and suburban housing developments. Low-pitched metal-sheet roofs are provided because they are the most cost-effective. Lack of space within the homes and tiny surround-gardens are major problems to residents seriously limiting lifestyle. Other problems associated with these developments concern environmentally intrusive effects, the need for better security and other social concerns, and storm water runoff. This thesis discusses a usable flat urban and suburban roofing for existing and new houses by means of a system known as 'C-beam'. A usable greened concrete flat roof replaces the traditional pitched metal-sheet. The new roof provides sitting space for family members and is used to grow plants in pots. A construction manual is to be developed by which the constructors will build the roofing without the use of cranes and other expensive sophisticated construction machinery. The house owner can construct their own flooring/roofing; that is, the process will provide additional jobs, and hence positively affect economy. The manual includes the means of effective control by municipal authorities to ensure adequate and safe standards. Greening of the roofs will not only provide the potential for growing food from the plants, but it will also improve the environment of the area, including the reduction of storm water run-off, by retaining some water in the soil on rooftops.
2

Analysis of a folded - plate concrete roof continuous with overhang

Walker, Scott Rogers January 1964 (has links)
Concrete folded plate structures have gained increasing use and popularity in the United States during the past fifteen years. They have proved to be especially economical in the construction of longspan roof systems. The folded plate shape has come into wide use because of its low coat of construction for long spans, high load carrying capacity, and rigidity. Moreover, the folded plate structure hu the structural advantage of thin shelled, curved surface structures, and is much easier and less expensive to construct than the latter. With reference to folded plate structures continuous over a support, the problem arises of relating the geometry of the folded plates to a number of points along the entire length of the plate edges, in an attempt to find the true condition of stress at these points, and to find the contribution of each stress condition to the overall effect. The investigation of this thesis consists of analyzing a reinforced folded plate concrete roof, continuous with overhang. The method of analysis used is that of successive iteration, i.e. balancing angle changes against internal moments and/or stresses. This method is similar to one presented by Howard Simpson - “Design of Folded Plate Roofs” - in the ASCE Proceedings, Vol. 84, January, 1958, but extended to apply to the cantilevered folded plates. / Master of Science
3

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.
4

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.

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