Thesis (M.S.)--Mississippi State University. Department of Civil Engineering. / Title from title screen. Includes bibliographical references.

Water is the essential resource that is becoming extremely scarce worldwide. The 21st century will further stress all available water resources through the growth and expansion of developing nations. It is not only the quantity of cheap water that is being depleted, but the quality of these waters is being endangered. Florida is an example where rapid development and an exploding population are competing for shrinking groundwater resources. Current water use does not address the use of alternative supplies and reuses in the United States. The objective of this research was to determine a strategy for augmenting existing water supplies with alternative sources that could be developed economically. Having reviewed numerous alternative sources, it was determined that runoff from roofs potentially provides a source that might meet the augmentation requirement for a small community of a population of 30,000 or less. This research has shown that the quality of water collected from five different roof surfaces meets the drinking water standards and will not degrade the current quality of the main source of water supply. This work not only required the collection of hydrological data from the roof systems, but chemically and biological analyzes samples for contaminants. Since rainfall events vary periodically and in duration, 100,000 meteorological events were analyzed for wind speed, relative humidity, rainfall intensity, and the rainwater runoff across five roofing surfaces to analyze variables that contribute to the effects on the water quality of the source. The model establishes the economics and the public health value of this water. The research assesses the local regulatory aspects of using the water with the outcome of a working objective and rational decision matrix that will permit agencies to select an optimal and safe utilization of the water sources.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 133-138). Also available on the World Wide Web.

Thesis (PhD.(Mining Engineering)--University of Pretoria, 2008. / Summary in English. On title page: Submitted in partial fulfilment of the requirements for the degree Philosophiae Doctor in the Faculty of Engineering, Built Environment and Information Technology, University of Pretoria. Includes bibliographical references.

Made available in DSpace on 2014-12-17T13:57:05Z (GMT). No. of bitstreams: 1 PatriciaRSAJ_DISSERT_pag1_ate_pag68.pdf: 1348342 bytes, checksum: 57897fc59a5e76f0d6f3ff154cabbc36 (MD5) Previous issue date: 2011-11-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aims to compare the thermal performance of tiles made from recycled material (waste packaging cardboard with aluminized film) with the tiles of fiber and bitumen, fiber cement and red ceramic with the aim of verifying the suitability of tile to be used in hot and humid climate of low latitude. The samples were selected according to the availability from Natal - RN market, as they are sold to the consumers. The methodology was based on studies that used experimental apparatus composed of thermal chambers heated by banks of incandescent bulbs, to analyze the thermal performance of materials. The tiles in the study were submitted to analysis of thermal performance, thermophysical properties and absorptance, using chambers of thermal performance, measuring the thermophysical properties and portable spectrometer, respectively. Comparative analysis of thermal performance between two samples of the recycled material with dimple sizes and different amounts of aluminum were made, in order to verify, if these characteristics had some interference on the thermal performance of them; the results showed no significant performance differences between the samples. The data obtained in chambers of thermal performance and confirmed by statistical analysis, showed, that the tile of recycled material have similar thermal performance to the tile of fiber cement. In addition to these tests was carried out the automatic monitoring of a building covered with tiles of recycled material, to verify its thermal performance in a real situation. The results showed that recycled shingles must be used with technical criteria similar to those used for fiber cement tiles, with regard to the heat gain into the building. Within these criteria should be taken into account local characteristics, especially in regions with hot and humid climate, and its use must be associated, according to the literature, to elements of thermal insulation and use of passive techniques such as vented attics, ceilings and right foot higher / O presente estudo teve como objetivo comparar o desempenho t?rmico entre telhas de material reciclado (res?duos de embalagens acartonadas com pel?cula aluminizada) e as telhas de fibra e betume, fibrocimento e cer?mica vermelha com a finalidade de verificar sua adequabilidade para uso em clima quente e ?mido de baixa latitude. As amostras foram selecionadas conforme a disponibilidade nas lojas de material de constru??o da cidade de Natal - RN, na forma como eram vendidas aos consumidores. A metodologia adotada foi baseada em estudos que utilizaram aparatos experimentais compostos por c?maras t?rmicas aquecidas por bancos de l?mpadas incandescentes, para analisar o desempenho t?rmico de materiais. Ainda, as telhas em estudo foram submetidas a an?lises de propriedades termof?sicas e de absort?ncia atrav?s de um medidor de propriedades termof?sicas e de um espectr?metro port?til, respectivamente. Foram realizadas an?lises comparativas de desempenho t?rmico entre amostras de material reciclado, com dois tamanhos de ondula??o e diferentes quantidades de alum?nio, com o intuito de verificar a interfer?ncia destas caracter?sticas no desempenho t?rmico das mesmas. Os resultados n?o apresentaram diferen?as significativas de desempenho entre as amostras. Os dados obtidos em c?maras de desempenho t?rmico e processados atrav?s da an?lise estat?stica demonstraram que a telha de material reciclado possui desempenho t?rmico similar ao da telha de fibrocimento. Al?m destas an?lises, foi realizado o monitoramento autom?tico de uma edifica??o coberta com a telha de material reciclado, para verificar seu desempenho t?rmico em uma situa??o real. A partir dos resultados verificou-se que telhas de material reciclado devem ser usadas com crit?rios t?cnicos similares aos utilizados para as telhas de fibrocimento, no que se refere ao ganho de calor para o interior da edifica??o. Dentre esses crit?rios, devem ser levadas em considera??o as caracter?sticas locais, principalmente em regi?es de clima quente e ?mido, e seus usos devem estar associados, de acordo com a literatura, a elementos de isolamento t?rmico e utiliza??o de t?cnicas passivas como ?ticos ventilados, forro e p? direito mais elevado

O Brasil possui a maior parte de suas terras em clima tropical. Sendo a cobertura o elemento construtivo mais exposto à radiação solar direta, toma-se um desafio aos pesquisadores e projetistas, atenuar as temperaturas nas coberturas das edificações e contribuir para o uso racional de energia. O objetivo desta pesquisa é monitorar o desempenho térmico de coberturas de fibrocimento em_ células-teste na cidade de Campinas, SP, com aplicação de técnicas passivas de resmamento. Utilizaram-se quatro células-teste: uma célula-teste de referência, e outras três com os sistemas: evaporativo, radiante e reflexivo, respectivamente, e monitoramento das temperaturas superficiais internas das telhas (TT' s) e temperaturas do ar dos áticos (T AA' s), no período de 21 de janeiro a 9 de fevereiro de 2006. Para o sistema de resmamento evaporativo foram utilizados ciclos de aspersão com diferentes intervalos no período todo. Entre as técnicas monitoradas, o melhor comportamento térmico foi verificado no 2° período (de 26 a 30/jan com aspersão contínua) na temperatura da superficie interna da telha do sistema evaporativo (TTevap = 23,2°C) apresentando um decréscimo de 1,3°C em relação a célulateste de referência e um acréscimo de 0,1 °C em relação as médias da temperatura do ar para o período. Nas médias da temperatura do ar dos áticos, o 2° período apresentou os menores valores para os sistemas: reflexivo (TAArefl =23,4°C) e evaporativo (TAAevap = 23,5°C), apresentando uma atenuação de 0,5°C e 0,4°C em relação a célula de referência respectivamente, além de uma elevação de 0,3°C em relação as médias da temperatura do ar externo. Os resultados, analisados através de tratamento estatístico, demonstram a viabilidade do uso do sistema evaporativo em condições climáticas de elevada umidade relativa do ar, contribuindo para atenuar os efeitos das hostilidades climáticas em coberturas das edificações._________________________________________________________________________________________ ABSTRACT: In Brazil, the tropical climate is predominant in most of regions. Roofing is the building component with the highest exposition to direct solar radiation. The challenge for researchers and designers is to achieve cornfort in the built environrnent and to contribute to energy saving, proposing roofing systems with good thermal insulation, and consequently lesser internal surface temperatures. The objective of this research is to monitor the thermal behavior of fiber-cement roofing and to present a discussion about the results obtained in cell-tests in the city of Campinas, SP, through passive cooling techniques. Four cell-tests were used: one cell-test was adopted as reference, and the other three were analyzed with evaporative, radiative and reflective systems, respectively. The evaporative system was tested with different aspersion cycles through spraying systems and intervals. The monitored parameters were the internal surface temperatures of the roofing tiles (TT s) and attic air temperatures (TAA's) in the period of January 21st to February 9th of2006. Among the monitored passive techniques, the best thermal behavior was observed in the 2nd period (iTom January 26th to 30th, corresponding to continue spraying), related to the internal surface temperature with the evaporative system (TTevap = 23,2°C). A reduction of 1,3°C was observed, as compared to the reference test-cell and and an increase of 0,1 °C in comparison with the average air temperature. In relation to the average of attic air temperature, the 2nd period presented the lowest temperature for reflexive system (T AArefl = 23,4°C) and evaporative system (TAAevap = 23,5°C); a reduction of 0,5°C and 0,4°C in relation of the reference test-cell respectively was observed; also, it showed an increase of 0,3°C as compared with air temperature. The results presented through statistical analyses demonstrated that the use of the evaporative system in climatic conditions with high relative humidity is viable, contributing, therefore, to attenuate the effects of climatic hostilities in the roofing buildings.

O Brasil possui a maior parte de suas terras em clima tropical. Sendo a cobertura o elemento construtivo mais exposto à radiação solar direta, toma-se um desafio aos pesquisadores e projetistas, atenuar as temperaturas nas coberturas das edificações e contribuir para o uso racional de energia. O objetivo desta pesquisa é monitorar o desempenho térmico de coberturas de fibrocimento em_ células-teste na cidade de Campinas, SP, com aplicação de técnicas passivas de resmamento. Utilizaram-se quatro células-teste: uma célula-teste de referência, e outras três com os sistemas: evaporativo, radiante e reflexivo, respectivamente, e monitoramento das temperaturas superficiais internas das telhas (TT' s) e temperaturas do ar dos áticos (T AA' s), no período de 21 de janeiro a 9 de fevereiro de 2006. Para o sistema de resmamento evaporativo foram utilizados ciclos de aspersão com diferentes intervalos no período todo. Entre as técnicas monitoradas, o melhor comportamento térmico foi verificado no 2° período (de 26 a 30/jan com aspersão contínua) na temperatura da superficie interna da telha do sistema evaporativo (TTevap = 23,2°C) apresentando um decréscimo de 1,3°C em relação a célulateste de referência e um acréscimo de 0,1 °C em relação as médias da temperatura do ar para o período. Nas médias da temperatura do ar dos áticos, o 2° período apresentou os menores valores para os sistemas: reflexivo (TAArefl =23,4°C) e evaporativo (TAAevap = 23,5°C), apresentando uma atenuação de 0,5°C e 0,4°C em relação a célula de referência respectivamente, além de uma elevação de 0,3°C em relação as médias da temperatura do ar externo. Os resultados, analisados através de tratamento estatístico, demonstram a viabilidade do uso do sistema evaporativo em condições climáticas de elevada umidade relativa do ar, contribuindo para atenuar os efeitos das hostilidades climáticas em coberturas das edificações._________________________________________________________________________________________ ABSTRACT: In Brazil, the tropical climate is predominant in most of regions. Roofing is the building component with the highest exposition to direct solar radiation. The challenge for researchers and designers is to achieve cornfort in the built environrnent and to contribute to energy saving, proposing roofing systems with good thermal insulation, and consequently lesser internal surface temperatures. The objective of this research is to monitor the thermal behavior of fiber-cement roofing and to present a discussion about the results obtained in cell-tests in the city of Campinas, SP, through passive cooling techniques. Four cell-tests were used: one cell-test was adopted as reference, and the other three were analyzed with evaporative, radiative and reflective systems, respectively. The evaporative system was tested with different aspersion cycles through spraying systems and intervals. The monitored parameters were the internal surface temperatures of the roofing tiles (TT s) and attic air temperatures (TAA's) in the period of January 21st to February 9th of2006. Among the monitored passive techniques, the best thermal behavior was observed in the 2nd period (iTom January 26th to 30th, corresponding to continue spraying), related to the internal surface temperature with the evaporative system (TTevap = 23,2°C). A reduction of 1,3°C was observed, as compared to the reference test-cell and and an increase of 0,1 °C in comparison with the average air temperature. In relation to the average of attic air temperature, the 2nd period presented the lowest temperature for reflexive system (T AArefl = 23,4°C) and evaporative system (TAAevap = 23,5°C); a reduction of 0,5°C and 0,4°C in relation of the reference test-cell respectively was observed; also, it showed an increase of 0,3°C as compared with air temperature. The results presented through statistical analyses demonstrated that the use of the evaporative system in climatic conditions with high relative humidity is viable, contributing, therefore, to attenuate the effects of climatic hostilities in the roofing buildings.

Este trabalho apresenta uma comparação de propriedades entre o cimento asfáltico de petróleo (CAP-20) e o mesmo CAP-20 modificado pela utilização de diferentes tipos de borrachas, visando avaliar uma alternativa para minimizar os problemas ambientais causados pela disposição de pneus usados. Foram preparadas misturas contendo 4, 8 e 12% em massa de SBS (estireno-butadieno-estireno) e Borracha Moída de Pneus (BMP) em duas granulometrias diferentes. Os comportamentos dessas misturas foram avaliados pelos ensaios de: penetração, ponto de amolecimento, separação de fase, resistência à tração, alongamento, flexibilidade, deformação permanente e recuperação elástica. Os resultados mostraram que é possível dispersar borracha de pneu em asfalto, embora os valores obtidos para as propriedades medidas não sejam tão favoráveis quanto às obtidas com SBS. / This work presents a comparison of properties between a CAP-20 asphalt and the same CAP modified using different kinds of rubbers, as a way to evaluate an alternative to minimize the environmental problems related to the disposal of used tires. Mixtures with 4, 8 and 12 wt% of SBS and two different particle size of scraped tire were prepared. The behaviors of these mixtures were evaluated by penetration, softening point, phase separation, tensile strength, elongation, flexibility, permanent deformation and elastic recovery tests. The results showed that it is possible to disperse tire rubber in asphalt, although the values obtained for some of the measured properties are not as good as the ones obtained with SBS.

The development of the construction industry brought the new methods of structural design, which have been introduced to engineers, although overall this phenomenon has increased building costs. A cost-effective construction is one of the major decision points during the definition of any engineering project, therefore, due to the opposing concepts of these two statements, revising design standards and codes are essential in order to provide adequate and cost-effective design requirements. A single-ply roof system is a relatively new method of roof construction that has been used in the building industry in recent decades, which seems to have undergone dramatic changes due to significant structural failures that have occurred through the years. Wind-induced damage on flat roofs is a common problem for low-rise buildings and much of this damage is initiated when the steel deck roof fails, leading to the overall roofing system collapse. The FM (Factory Mutual) design recommendations, which is a standard that recommends allowable dimensions and wind rating for the roofing products, have provided tabulated steel deck span dimensions and fasteners distance for many years. To update the FM design recommendations extensive experimental and analytical investigations are required. In the current study an experimental program was conducted at the National Research Council of Canada (NRC) on flat roofing systems, for simulating the wind uplift effect on several roofing systems samples, as recommended by FM design recommendations. A Finite Element Model (FEM) of the same roofing systems as those used in the experimental cases was developed and different loading patterns were analysed for providing a better simulation of the deflection, moments and forces responses, as measured during the experiments. The FEM was validated with the experimental results and was further employed for applying the FE analysis for more steel deck span dimensions and wind rating cases, as provided in the FM design recommendations tables. These results were reported to the Single Ply Roof Industry (SPRI) Committee where the updating of the FM design tables is currently under discussion.

CO2 is one of the main gases accountable for the increment of the greenhouse effect, of climate changes, and of environmental degradation arising from this ecological unbalance. Civil construction is one of the main sources of CO2 emissions, using construction techniques that are more sustainable can contribute to the reduction of those emissions. Furthermore, the energy content of materials must be taken into account as well due to the fact that the consumption of petroleum by-products increases the CO2 indexes in the atmosphere. It becomes then clear that the less energy is consumed, even those renewable, the less environmental impact there is. Thus, it is indispensable to analyse not only the emissions of CO2 but also the energy content of materials used in three roofing technologies under scrutiny in this research: green roofs, fibre cement, and ceramic tiles. Green roofs are a sustainable alternative to be implemented in covering the top of buildings. This research, therefore, aims to compare the CO2 emission to the energy content of two green roof solutions and of two traditional coverage solutions in the pre-operational phase in the cities of Porto Alegre and Santa Maria, both in the state of Rio Grande do Sul. The method used to identify left from the layers and constituents in each green cover, and the raw materials used in traditional roofs, measuring how much material was used for each cover, analyzing all the material traversed by the means of transport, quantifying emissions CO2 and energy consumption of materials by processes fabrication them and finally to compare all results. Common belief is that green roofs have the potential to mitigate environmental damages, especially those caused by the civil construction sector concerning CO2 emissions and energy consumption in the pre-operational phase, just as advantages in the operational phase are described. Such hypothesis was confirmed for the tested cover. However, among the possibilities discussed below for closing the top of buildings, green roofs are the only technology capable of mitigating environmental damage, in particular, the emission of carbon dioxide, and provide an environmental service to the community carbon sequestration to throughout his life . Nonetheless, amongst the building coverage possibilities herein analysed, green roofs are the only technology capable of integrally mitigating environmental damages in a few years, especially the emission of carbon dioxide, and also the only technology capable of providing an environmental service to the collectivity of carbon sequestration to throughout his life. / O CO2 é um dos principais gases responsáveis pelo incremento do efeito estufa, das mudanças climáticas e da degradação ambiental decorrente deste desequilíbrio ecológico. Sendo a construção civil uma das principais responsáveis pela emissão de CO2, o uso de técnicas construtivas mais sustentáveis pode contribuir para a redução dessas emissões. Além disso, o conteúdo energético dos materiais também é importante ser considerado, pois além de incrementar, através de consumo de derivados de petróleo, os índices de CO2 na atmosfera, o menor consumo de energia possível, mesmo as renováveis, representa menores impactos ambientais. Assim sendo, imprescindível analisar não só a emissão de CO2, como também o conteúdo energético dos materiais empregados nas três tecnologias de cobertura objetos de estudo desta pesquisa: coberturas verdes, de fibrocimento e de telhas cerâmicas. As coberturas verdes são uma possibilidade sustentável a ser implementada no fechamento de topo de edificações. A presente pesquisa visa a comparar as emissões de CO2 e o conteúdo energético de duas soluções de cobertura verdes e duas soluções de coberturas tradicionais, na fase pré-operacional, localizadas em Porto Alegre e outra em Santa Maria RS. O método utilizado partiu desde identificar as camadas e elementos constituintes em cada cobertura verde, bem como os insumos utilizados nas coberturas tradicionais, mensurar quanto material foi utilizado para cada cobertura, analisar o percorrido de todos os materiais pelos meios de transportes, quantificar as emissões de CO2 e o consumo energético dos materiais pelos processos de fabricações dos mesmos e finalmente comparar todos os resultados. O senso comum considera que as coberturas verdes têm o potencial de mitigar danos ambientais, especialmente os causados pelo setor da construção civil de emissão de CO2 e de consumo energético na fase pré-operacional, da mesma forma como são descritas as vantagens na fase operacional. Tal hipótese se confirmou para as coberturas avaliadas. Dentre as possibilidades aqui analisadas para fechamento de topo de edificações, as coberturas verdes são a única tecnologia capaz de mitigar os danos ambientais, em especial, a emissão de dióxido de carbono, e fornecer um serviço ambiental à coletividade de sequestro de carbono ao longo de sua vida útil.