252 resultados para Roofing, Bituminous.


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The performance of breathable roofing membranes (BRM’s) in buildings where bats roost have been investigated using experimental measurements and numerical simulations. Measurement techniques as outlined in BS EN ISO 12572 of membranes from manufacturers in its pure state and those that have been contaminated with bat urine, faeces and natural oils transmitted via fur because they were found in bat roost have been tested for their permeability functions. The findings from this shows that there are significant differences between the functionality of the pure samples compared to the contaminated samples, with an average of about 20-30% reduction in functionality. This paper integrates modelling techniques using a heat, air and mass software with a simulink interface on a Matlab platform to investigate the moisture transfer properties of the BRMs. The simulation results demonstrate high level of condensation formation when the BRM is contaminated as compared to when it is not.

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The objective of the present work was to evaluate the effects of 14 years of weathering exposition on the microstructure and mineral composition of cementitious roofing tiles, still in service, reinforced with fique fibres (Furcrae gender). The results show that tiles under weathering exposition presented higher water absorption and apparent void volume than tiles under laboratory exposition. The continuous hydration of cement and natural carbonation filled the smaller pores but contrarily the large pores remained in the porous fibre to matrix interface in the samples exposed to weathering. On the other hand, their microstructure presented lower air permeability than samples aged in the internal environment of the laboratory. Besides, in the weathering aged tiles takes place a more intensive hydration process as it was identified greater amount of hydrated phases than in the laboratory aged specimens. The present results contribute to understanding the consequences of tropical weathering on the fibre-cement degradation. (C) 2010 Elsevier Ltd. All rights reserved.

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The present work evaluated the effects of accelerated carbonation on mechanical and physical characteristics of cementitious roofing tiles reinforced with vegetable fibre. The maximum load and toughness of the tiles have increased approximately 25% and 80% respectively as a consequence of the accelerated carbonation. Water absorption and apparent porosity decreased with carbonation while bulk density increased as a clear indication of the densification of the composite. The improvement on the mechanical performance suggests that the fibres retained their tensile strength in the inorganic matrix. Results of specimens extracted from the tested tiles after approximately 480 days in laboratory environment and further aged indicate that soak and dry cycles promoted some leaching of hydration products and more voids and lower density when performed before carbonation. The results indicate the utilization of accelerated carbonation as an effective procedure to mitigate the degradation suffered by the cellulose fibres in the less aggressive medium. (C) 2009 Elsevier Ltd. All rights reserved.

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The main objectives of this work are to establish a relationship between solar radiation and equivalent temperatures for the radiation heat source (oven) to be used in the laboratory and to determine the impact of solar radiation on the absorption and evaporation potential of roofing tiles (glazed and unglazed). Based on the results obtained, it is justifiable to conclude that solar radiation do affect the evaporation and absorption potential of the glazed and unglazed tiles. There is a trend of decrease in both the absorption and evaporation potential of both tiles when exposed to decreasing solar radiation. The evaporation potential of the roof tiles is much higher than its absorption potential. This is clearly displayed in both types of tiles.

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Integrating solar energy devices with building products is a rapidly growing market in the building industry. The aim is to make solar devices that integrate into a standard facade, window, roof tile, membrane roof or long run roof. These serve as weatherproofing for a building and also generate electrical and thermal energy.

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The use of onsite renewable energy cogeneration from structural building elements is a relatively new concept, and one that is gaining considerable interest in the building industry. In this study the design, development, testing and production methods for a novel building integrated photovoltaic/thermal (BIPVT) solar energy cogeneration system are examined and discussed.

During the analysis of the design, adhesives (ADH), resistance seam welding (RSW) and autoclaving (ATC) were identified as the most appropriate for fabricating BIPVT panels for roofing and façade applications. Of these manufacturing methods ADH was found to be most suitable for low volume production systems due to its low capital cost.

Furthermore, a prototype panel was fabricated using ADH methods and exhibited good thermal performance. In addition it was shown, using experimental testing, that the performance of a BIPVT could be theoretically predicted using a one-dimensional heat transfer model. Furthermore, the model was used to suggest further improvements that could be made to the design. Finally, a transient simulation of the BIPVT was performed in TRNSYS and was used to illustrate the long term benefits of the system.

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Esta pesquisa foi conduzida com o objetivo de avaliar diferentes tipos de coberturas em instalações para aves, por meio do Índice de Temperatura de Globo Negro e Umidade (ITGU), Carga Térmica de Radiação (CTR) e Entalpia (H). O experimento foi conduzido na Universidade Estadual de Goiás, entre os meses de abril e maio de 2011, sendo composto por cinco tratamentos (coberturas): CA -Telha de cimento-amianto; BA -Telha de bambu; BAP -Telha de bambu pintada de branco; FB -Telha de fibra vegetal e betume; FBP -Telha de fibra vegetal e betume pintada de branco, com 15 repetições, sendo as repetições os dias de medição. Dentre os horários estudados, o considerado menos confortável foi às 14h, sendo que a cobertura de fibra vegetal e betume foi a que apresentou maior valor de ITGU (84,1) quando comparada às demais coberturas, caracterizando uma situação de menor conforto térmico, não sendo observada diferença para CTR e H entre os tratamentos na região estudada.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coal is an aggregation of vegetal matter with varying small amounts of mineral and animal matter which have been so changed by the processes of sedimentation, decay and metamorphism that it has become a dense, dark, combustible substance. It occurs in beds varying in thickness from one foot or less to over 300 feet. The horizontal extent of a bed is sometimes continuous over an area as large as the State of Montana.

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Artículo a partir de extracto de la memoria de proyecto de la rehabilitación de la nave 8B de Matadero Madrid

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In this study, the behavior of bituminous mixes made with sewage sludge ash (SSA) as mineral filler was investigated. The behavior of these mixes was evaluated with the Cantabro, indirect tensile strength, water sensitivity, permanent deformation, and resilient modulus tests. The results show that SSA waste may be used in bituminous mixes at approximately 2–3% weight percent, maintaining adequate levels of cohesion and adhesion in the mixtures, which is comparable to mixtures made with active fillers such as hydrated lime and cement. Moreover, its use does not increase permanent deformations. However, the resilient modulus test gave slightly lower results for mixes made with SSA than for mixtures made with other fillers. It may be concluded that SSA waste may be used as a filler for bituminous mixes with better results than for mixes made with limestone fillers and with similar results for mixes made with other fillers such as hydrated lime and cement.

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Bitumoid contents in metalliferous sediments from axial parts of the East Pacific Rise (EPR) have been studied. Maximal concentrations of bitumoid matter and aromatic hydrocarbons have been found in the axial zones of the EPR as a result of hydrothermal processes and accumulation of endogenous matter in the sediments. Distribution of bitumoids and hydrocarbons coincides with deposition of ore minerals that indicates similarity of their sources.

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Cover title.