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Material para construção civil a partir de lodo de estação de tratamento de água, lama de polimento de mármore e resíduo de produção de cal / Construction material from water treatment sludge, marble polish mud and lime production wasteHackbart, Fernanda Meireles 11 December 2015 (has links)
O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.
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Le concepteur et les matériaux de construction: éléments de réflexion pour une reconfiguration des circuits de l'économie matérielle par les pratiques architecturales contemporaines / Designer and the construction materials: elements of reflection for a reconfiguration of the circuits of material economy through contemporary architectural practicesGhyoot, Michaël 12 September 2014 (has links)
Cette recherche s'intéresse aux matériaux de construction et aux architectes. Elle explore les circuits le long desquels circulent les matériaux et étudie les dispositifs dont ils sont munis pour rendre cette circulation possible. Elle se penche sur les rôles que jouent et sur ceux que pourraient jouer les concepteurs au sein de ces circuits et en regard de ces dispositifs.<p>Ce travail s'inscrit dans le cadre d'une réflexion sur les pratiques de l'aménagement de l'espace bâti. Au cours de son trajet entre son site de production et celui de sa mise en œuvre (c'est-à-dire le chantier de construction) – et même au-delà, lorsqu'une transformation libère des éléments constructifs – un matériau passe par de nombreuses étapes. Parmi toutes celles-ci, le passage par le moment de la conception est un élément central de cette recherche (même si d'autres étapes seront également explorées au fil de pages de ce travail). Quels rôles les concepteurs jouent-ils au sein de ces vastes assemblages d'acteurs et de dispositifs qui se déploient le long des trajectoires des matériaux de construction ? Comment les concepteurs sont-ils affectés par ces assemblages et comment peuvent-ils les affecter en retour ?<p>Répondre à ces questions engage une exploration des principales trajectoires des matériaux de construction et un examen attentif des dispositifs dont ils sont munis au fil de ce processus. C'est ce à quoi s'attache la première partie de cette recherche, dont la portée est plutôt descriptive. Mais elle ne s'arrête pas à ce stade. Elle comporte également une seconde partie, plus prospective et critique. Cette recherche propose en effet d'explorer certaines pistes de reconfiguration au sein de ces assemblages. Elle examine plusieurs questions touchant aux limites des circuits de l'économie matérielle : par quelles modifications faudrait-il en passer pour que des matériaux actuellement exclus des circuits les plus courants de l'économie matérielle puissent malgré tout y circuler ? D'autres arrière-plans axiologiques pourraient-ils être mis en jeu dans les circuits de l'économie matérielle ?<p>La présente recherche repose sur l'hypothèse que les concepteurs peuvent effectivement contribuer à la transformation progressive des circuits de l'économie matérielle. Ils ont vraisemblablement un rôle à jouer dans la possibilité d'ouvrir ces circuits à de nouveaux matériaux, et de contribuer ainsi à établir des pratiques plus à même de répondre aux enjeux écologiques et politiques auxquels sont confrontés notre planète et ses habitants. Bien sûr, les concepteurs n'ont pas l'exclusivité de tels changements. D'autres acteurs peuvent, et même doivent, participer à de tels efforts. Ce sont pourtant principalement les concepteurs qui retiendront l'attention de cette recherche. Il s'agit dans ce cadre d'explorer les conditions d'un tel changement, et ce tant d'un point de vue méthodologique que d'un point de vue pratique.<p>/<p>This research investigates the relation between construction materials and architects. It examines the circuits along which the materials circulates and it studies the devices that are embedded in the materials in order to render this circulation feasible. It looks into the roles that are played, and those that could be played, by the designers within these circuits and in regard with these devices.<p>This work is part of a reflection on the practices of designing and constructing the built environment. During its journey between its production site and that of its implementation (i.e. the construction site) – and even beyond, when a transformation frees again constructive elements – a construction material travels through many steps. Among all these, the passage through the design process is a key element. What role do the designers perform within these networks of actors and devices? How are they affected by these assemblages and how can they affect them in return?<p>Answering these questions undertakes an exploration of the main trajectories of construction materials and of the devices that are embedded throughout these processes. This is the topic of the first part of the research. At this point, the scope is mainly descriptive. But the research goes further: it also involves a more critical and prospective dimension. It proposes indeed to discuss several possible reconfigurations within these assemblages. What would be necessary in order to include new materials that are currently excluded from the main circuits of material economy? Could other axiological backgrounds be represented within these circuits?<p>This research is based on the assumption that designers can effectively contribute to the gradual transformation of the circuits of material economy. They can probably help alternative materials to circulate in more standard circuits, and thus help to establish new practices that are more likely to respond to environmental and social issues. Of course, the designers do not have a monopoly on such changes. Other actors may, and even must, participate in such efforts. Yet, the main focus of this research is the designer. It explores the conditions of such a change, both from a methodological and practical perspective. / Doctorat en Art de bâtir et urbanisme / info:eu-repo/semantics/nonPublished
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Porovnání nákladů výstavby rodinného domu z klasických materiálů a z materiálů přírodních / Cost comparison of houses made of classic materials and houses made of natural materialLošáková, Jana January 2016 (has links)
This diploma thesis is focused on a comparison of construction cost of the house made of classic materials with the equivalent made of natural building materials and consequently on comparison of both construction variants. In order to perform those tasks, the used natural building materials were defined. Furthermore, the specific options of usage of these natural building materials as well as the used composition structures were introduced. The thesis concludes with a price calculation of the constructions made of natural building materials which were not available in the common budgetary software. The appendix of the thesis contains budgets for the first variant, where the house is made of natural building materials, and also for the second variant, where the house is made of classic materials.
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Energy efficiency interventions for residential buildings in Bloemfontein using passive energy techniquesKumirai, Tichaona January 2010 (has links)
Thesis (M. Tech. (Mech. Eng.)) -- Central University of Technology, Free state, 2010 / The purpose of this research is to minimize the use of active systems in providing thermal comfort in single-family detached, middle to high income residential buildings in Bloemfontein. The typical case study house was selected according to the criteria as reviewed by Mathews et al., (1999).
Measurements were taken for seven days (18 – 24 May 2009). The measurements were carried out in the winter period for Bloemfontein, South Africa. Ecolog TH1, humidity and temperature data logger was used in doing the measurements. These measurements included indoor temperatures and indoor relative humidity.
Temperature swings of 8.43 ºC and thermal lag of 1 hour were observed. For the period of seven days (168 hours), the house was thermally comfortable for 84 hours.
Thermal analysis for the base case house was done using Ecotect™ (building analysis software) and the simulated results were compared with the measured results. A mean bias error (MBE) of between 10.3% ≤≤11.5% was obtained on the initial calibration. The final calibration of the model yielded error between0.364% ≤≤0.365%. The final calibration model which presented a small error was adopted as the base case.
Passive strategies were incorporated to the Ecotect™ model (final calibrated model) singly and in combination; then both thermal and space load simulations were obtained and compared to simulations from the original situation (base case) for assessing improvements in terms of thermal comfort and heating, ventilation and air conditioning (HVAC) energy consumption. Annual HVAC electricity savings of up to 55.2 % were obtained from incorporating passive strategies in combination. Incorporating passive strategies resulted in small improvements in thermal comfort.
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Rural housing and rural development in Northern NamibiaWienecke, Martin Andreas 11 1900 (has links)
When Namibia became independent in March 1990, the new government pledged to
alleviate poverty, unemployment and to improve the living standards of the
formerly disadvantaged groups in the country. Rural development was presented as
one of the priorities because the majority of the people live in or still have
strong ties to the rural areas.
Rural housing and rural development consist of a number of components. Both have
similar objectives, inter alia, the improvement of living standards. Development
efforts are often impeded by an urban bias in government policies and projects. In
the case of Namibia, certain areas do not even have a formulated policy to guide
developments, especially in communal areas with a high population concentration.
This study explores to what extent the government has realised rural development
policies and in particular rural housing in Northern Namibia as a means to improve
living standards. / Public Administration and Management / M.A. (Development Administration)
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An investigation into the time and cost factors for a decision between in-situ and hybrid concrete constructionPiek, Philippus Jacobus 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The construction industry is a competitive market and contractors need to keep up-to-date with new
construction methods and technologies. Project teams in South Africa are required to make decisions
during the early stages of construction projects. These decisions often need to be made in a short time
period, and include the decision between various construction methods, such as the decision between
in-situ concrete construction and hybrid concrete construction.
Hybrid concrete construction is a combination of pre-fabricated concrete and cast in-situ concrete to
obtain the supreme benefits of their different construction qualities. This method of construction is
ultimately used to achieve faster, and occasionally, more cost effective construction. Hybrid concrete
construction, today, is a well-known term in the construction industry and is widely used in the UK
and other developed countries. However, the use thereof is limited in South Africa, and in-situ
concrete construction remains the conventional method of construction. Possible reasons for the
limited use of hybrid concrete construction are investigated in this study. With the intent of improving
the construction industry of South Africa, guidelines are provided to assist project teams in a decision
between in-situ concrete construction and hybrid concrete construction.
The decision between construction methods is based on many factors, such as project time, cost,
quality, safety, environmental performance, socio-economic aspects (labour) and client satisfaction.
Project time and cost are, however, the most important of these factors. It is stated that the structure of
a building represents typically only 10 % of the construction cost, however, the choice of construction
method and material can have significant effects on the cost of other elements throughout the life cycle
of construction projects. It is therefore important to measure the whole life cycle cost when deciding
between construction methods, such as in-situ concrete construction and hybrid concrete construction.
The aim of this study is to identify and investigate the factors that influence project time and cost,
throughout the life cycle of construction projects, and to provide a framework that can assist project
teams in their decision between in-situ concrete construction and hybrid concrete construction in
South Africa. The decision between these two construction methods is influenced by a vast number of
variables that may be difficult to quantify. The framework therefore consists of qualitative information
that can assist project teams in their decision.
The framework provided in this study includes the factors that have an influence on the time and cost
for a decision between in-situ concrete construction and hybrid concrete construction. These factors
are identified for the three primary phases in the life cycle of construction projects. These phases are
the design phase, the construction phase and the maintenance phase. / AFRIKAANSE OPSOMMING: Die konstruksiebedryf is 'n kompiterende mark en kontrakteurs moet op datum bly met nuwe
konstruksie metodes en tegnologieë. In Suid-Afrika word daar van projek spanne vereis om vinnige
besluite gedurende vroeë stadiums van 'n projek te neem. Hierdie besluite moet dikwels in 'n kort
tydperk geneem word, en sluit die besluit tussen verskillende konstruksie metodes in, byvoorbeeld die
besluit tussen in-situ en hibriede beton konstruksie.
Hibriede beton konstruksie (HBK) is 'n kombinasie van in-situ en voorafvervaardigde beton elemente.
HBK word in die algemeen gebruik om te baat uit 'n vinniger konstruksie tydperk, en kan soms ook ‘n
meer koste-effektiewe metode van konstruksie wees. HBK word gesien as 'n bekende term in die
konstruksiebedryf en word veral toegepas in ontwikkelde lande soos die VSA, Japan en Engeland. Die
toepassing daarvan in Suid-Afrika is egter beperk. In Suid-Afrika word in-situ beton konstruksie nog
steeds die meeste gebruik en staan dus bekend as die mees algemene metode van konstruksie. Hierdie
studie ondersoek moontlike redes vir die beperkte gebruik van HBK in Suid-Afrika. Met die oog op 'n
verbeterde konstruksiebedryf in Suid-Afrika, word rigylyne voorsien, wat projek spanne kan gebruik
vir 'n besluit tussen in-situ en hibriede beton konstruksie.
Daar is verskeie faktore wat 'n rol speel in die besluit tussen twee konstruksie metodes. Hierdie faktore
sluit in, die tyd, koste, kwaliteit, veilighed, omgewings impak, sosio-ekonomiese aspekte (soos arbeid)
en kliënt tevredenheid, van 'n projek. Tyd en koste is egter die belangrikste van hierdie faktore. Die
metode waarvolgens 'n struktuur gebou word kan 'n beduidende uitwerking op die koste van ander
elemente in die lewensiklus van 'n konstruksie projek hê. Dit is gevolglik belangrik om die hele
lewensiklus koste in ag te neem wanneer daar besluit moet word tussen verskeie konstruksie metodes,
soos in-situ en hibriede beton konstruksie.
Die doel van hierdie studie is gevolglik om die faktore wat 'n invloed het op die tyd en lewensiklus
koste van konstruksie projekte te identifiesieer. Hierdie faktore word dan gebruik om 'n raamwerk
voor te stel. Projek spanne kan hierdie raamwerk gebruik as 'n riglyn om te besluit tussen in-situ en
hibriede beton konstruksie. Die besluit tussen hierdie twee konstruksie metodes is afhanklik van 'n
groot aantal veranderlikes, wat moeilik is om te kwantifiseer. Die raamwerk bestaan dus uit
kwalitatiewe inligting wat projek spanne kan gebruik om 'n ingeligte besluit te neem oor in-situ en
hibriede beton konstruksie.
Die raamwerk wat in hierdie studie voorgestel word sluit dus die faktore in wat 'n invloed het op die
tyd en koste vir 'n besluit tussen in-situ en hibriede beton konstruksie. Hierdie faktore is geïdentifiseer
vir die drie primêre fases in die lewensiklus van 'n konstruksie projek. Hierdie fases is die ontwerp
fase, die konstruksie fase en die onderhoud fase.
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Effets de la variabilité des propriétés de matériaux cimentaires sur les transferts hygrothermiques : développement d’une approche probabiliste / Variability impacts of cementitious materials properties on the hygrothermal tranfers : development of a probabilistic approachIssaadi, Nabil 02 December 2015 (has links)
Ce travail concerne la modélisation numérique et expérimentale de la variabilité des propriétés thermo-hydriques de matériaux cimentaires en vue de l’évaluation de son impact sur la prédiction du comportement hygrothermique de parois de bâtiments. Une approche probabiliste qui prend en compte la variabilité spatiale des propriétés de matériaux lors des transferts couplés de chaleur et d’humidité a été développée. Elle est basée sur la génération, par la décomposition modale de Karhunen-Loève, de champs aléatoires spatialement corrélés. Une implémentation d’un modèle de transfert hygrothermique dans un code de simulation numérique a été ensuite réalisée en adoptant cette démarche stochastique. Cette dernière, qui considère comme variables d’entrée des champs aléatoires, permet de quantifier l’incidence de cette variabilité sur le comportement hygrothermique d’une paroi de bâtiment. Une étude préalable, dédiée à l’évaluation de l’incidence de la variabilité aléatoire du coefficient de diffusion, a été entreprise en considérant une variabilité de ±30% pour un mortier et de ±20% pour un BHP suivant une loi de distribution normale. Aussi, nous avons relevé un certain nombre d’incertitudes possibles de la teneur en eau à saturation tout en montrant leurs effets sensibles sur le résultat de la prédiction du comportement hygrothermique. Ces études ont permis de mettre en exergue l’importance de la prise en compte des incertitudes sur les données du matériau lors des simulations numériques des transferts hygrothermiques. Sur le plan expérimental, une campagne d’évaluation de la variabilité spatiale des paramètres les plus influents a été menée. Cette campagne a été réalisée sur un voile de dimension 2x1,2 m fabriqué au laboratoire. À l’issue de ce programme expérimental, l’espérance, la variance et la longueur de corrélation des propriétés étudiées (porosité à l’eau, perméabilité à la vapeur, isotherme de sorption et perméabilité au gaz) ont été déterminées. Ces trois paramètres sont indispensables pour la bonne mise en œuvre de la décomposition de Karhunen-Loève. Aussi, une autre campagne de caractérisation expérimentale a été menée sur des pâtes de ciment, mortiers et béton. Elle a été divisée en trois grandes parties selon les propriétés étudiées : (i) Les propriétés microstructurales et d’hydratation où l’on retrouve les mesures des porosités à l’eau et au mercure ainsi que les distributions de la taille des pores et une analyse de l’effet du taux d’hydratation de matériaux cimentaires sur leurs propriétés hygrothermiques. (ii) Les propriétés hydriques : dans cette partie, une analyse sous différents angles (évolution en fonction de l’âge des matériaux, en fonction de la température, effet des constituants des matériaux, etc.) a été réalisée sur les isothermes de sorption et sur la perméabilité à la vapeur d’eau. (iii) Les propriétés thermiques où des mesures de conductivités thermiques et de chaleurs spécifiques ont été effectuées. Les résultats de l’étude ont mis en exergue les limites des approches déterministes suite à leurs confrontations avec les résultats obtenus par l’approche probabiliste, mise en œuvre dans le cadre du présent travail. / This study deals with the experimental and the numerical modeling of the variability properties of cement based materials to evaluate their effects on the prediction of hygrothermal behavior of building envelops. A probabilistic approach taking into account the spatial variability of the materials properties during the coupled heat and mass transfer has been developed. It is based on the generation of spatially correlated random fields by the Karhunen Loève decomposition. The stochastic model’s program has been implemented in a numerical simulation code. Using this tool that considers the input variables as random fields, the impact of this variability on the hygrothermal behavior of building envelops was quantified. A prior study dealing with the assessment of the effect of the diffusion coefficient random variability was carried out by considering a variation of ±30% for mortar and ±20% for high performance concrete (HPC) according to a normal distribution. Also, we have identified some possible uncertainties of the water content at saturation and showed their significant impact on the prediction of hygrothermal behavior of the material. These studies highlight the importance of considering the data uncertainties of building materials during numerical simulation of hygrothermal transfers. At the experimental level, the spatial variability of the most influential parameters was evaluated. It was carried out by manufacturing a concrete wall in lab. At the end of this experimental program, the expected value, standard deviation and the correlation length of the studied properties (water porosity, water vapor permeability, sorption isotherm and gas permeability) were determined. These three parameters are important for the successful implementation of Karhunen Loeve decomposition. Also, another experimental program was conducted on cement pastes, mortars and concrete. It was divided into three parts according to the studied properties:(i) Hydrations and microstructural properties which include the measurement of water and mercury porosity, the pore size distributions and an analysis of some techniques for stopping cement hydration.(ii) Hydric properties: where an analysis of the sorption and the water vapor permeability was performed considering their evolution with materials ages, temperature…(iii) Thermal properties where measurement of specific heat and thermal conductivity were performed. The result of the study highlighted the limits of deterministic approaches after their confrontation with the obtained results using the probabilistic one developed in this work.
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A Study of Building Procedure in the Dominican Republic : How to develop a sustainable building process. -Are there applicable models and techniques from Sweden?Myrberg, Kristina, Knutsson, Caroline January 2009 (has links)
This report is the final thesis and the conclusion of the final project that was done during the spring semester of 2009, in the city of Santo Domingo, The Dominican Republic, West Indies by Caroline Knutsson and Kristina Myrberg. The project is based on the field studies that are done in the investigation together with the information from interviews from the construction sites and the collected information from the research. The focus is concentrated in an investigation about the construction techniques that are used, the building materials and the working conditions on the construction site. A study has been done of a Swedish model of urban planning with environmental objects (SAMS), made by the National Board of Housing, Building and Planning (Boverket), and successively applied in a project in South Africa. With the purpose of investigate if it is possible to apply the same model in the Dominican Republic, a review of the current environmental- and urban planning in the country has been done. Through the studies we think that an introduction of planning with environmental objectives and a development towards a sustainable and ecological society is possible in the Dominican Republic. After field studies on the construction sites, it was relevant to discuss the working conditions and the safety for the constructers. The thesis also deal with the waste problem, since it is a problem that is not taken care of neither in the building sector or in the society. The suggestion is to recycle and reuse more of the waste, especially all the concrete that is used in the buildings. Sweden have come a long way ahead in the questions of sustainable housing and ecological building, to spare and reduce the effect the building sector has on the environment. This is questions of more importance than ever today, when we are seeing the effects of the climate change in the world. An investigation is done of the possibility to apply any of the methods that are used in Sweden today to make the housing more sustainable and environmentally friendly, also in The Dominican Republic. The result is some suggestions of methods and technologies that might be applicable in the Dominican Republic.
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A Study of Building Procedure in the Dominican Republic : -How to develop a sustainable building process.-Are there applicable models and techniques from Sweden?Myrberg, Kristina, Knutsson, Caroline January 2009 (has links)
<p>This report is the final thesis and the conclusion of the final project that was done during the spring semester of 2009, in the city of Santo Domingo, The Dominican Republic, West Indies by Caroline Knutsson and Kristina Myrberg.</p><p>The project is based on the field studies that are done in the investigation together with the information from interviews from the construction sites and the collected information from the research. The focus is concentrated in an investigation about the construction techniques that are used, the building materials and the working conditions on the construction site. A study has been done of a Swedish model of urban planning with environmental objects (SAMS), made by the National Board of Housing, Building and Planning (Boverket), and successively applied in a project in South Africa. With the purpose of investigate if it is possible to apply the same model in the Dominican Republic, a review of the current environmental- and urban planning in the country has been done. Through the studies we think that an introduction of planning with environmental objectives and a development towards a sustainable and ecological society is possible in the Dominican Republic.</p><p>After field studies on the construction sites, it was relevant to discuss the working conditions and the safety for the constructers.</p><p>The thesis also deal with the waste problem, since it is a problem that is not taken care of neither in the building sector or in the society. The suggestion is to recycle and reuse more of the waste, especially all the concrete that is used in the buildings. Sweden have come a long way ahead in the questions of sustainable housing and ecological building, to spare and reduce the effect the building sector has on the environment. This is questions of more importance than ever today, when we are seeing the effects of the climate change in the world. An investigation is done of the possibility to apply any of the methods that are used in Sweden today to make the housing more sustainable and environmentally friendly, also in The Dominican Republic. The result is some suggestions of methods and technologies that might be applicable in the Dominican Republic.</p>
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Proposta de protocolo para mediação de concentrações de radônio proveniente de rochas graníticas em marmorarias / Protocol proposal for radon concentration mensuration from granitic rocks in marble factoryClaro, Flávia Del 14 September 2016 (has links)
CNEN / Radionuclídeos de ocorrência natural como o radônio (222Rn), seus produtos de decaimento e demais elementos provenientes das séries radioativas do urânio (238U e 235U) e do tório (232Th) representam importante fonte de exposição humana à radioatividade natural. A avaliação dos efeitos radiobiológicos e dos riscos a saúde decorrentes da exposição da população mundial a radionuclídeos naturais é uma preocupação crescente. Elementos como o radônio (222Rn), o torônio (220Rn), o rádio (226Ra), o tório (232Th) e o potássio (40K) podem ser encontrados em materiais comumente utilizados na construção de casas e edifícios. Nesse panorama, destaca-se o estudo da radioatividade proveniente de mármores e granitos, já que sob certas condições os níveis de radioatividade desses materiais podem ser perigosos requerendo, assim, a implementação de medidas mitigatórias para a utilização dos mesmos. Este trabalho apresenta um protocolo técnico de controle de exposição humana à radioatividade natural proveniente de rochas graníticas em marmorarias. O protocolo foi elaborado com base em medidas realizadas da concentração do gases 222Rn e 220Rn em rochas graníticas brasileiras que são comumente comercializadas nacionalmente e exportadas. Para as medidas de concentração de 222Rn e 220Rn foram utilizados os equipamentos AlphaGUARD (Saphymo GmbH) e RAD7 (Durridge Company), respectivamente. Para as medidas em ambos os equipamentos utilizados, as amostras de granito foram lacradas em frascos de vidro por 40 dias para que os radionuclídeos 226Ra e 222Rn entrassem em equilíbrio secular. As medidas foram realizadas no Laboratório de Física Nuclear Aplicada da Universidade Tecnológica Federal do Paraná. Paralelamente, detectores de estado sólido CR-39 foram instalados nos ambientes de uma marmoraria da região de Curitiba-Paraná para a avaliação das concentrações de 222Rn nos postos de trabalho. Os detectores CR-39 ficaram expostos por um período aproximado de 90 dias e, posteriormente, foram submetidos à revelação química e leitura manual em microscópio óptico. Os valores médios das concentrações de 222Rn das amostras de granito variaram de 32 Bq/m3 a 1,7 KBq/m3. Os resultados obtidos ressaltam a importância dessa pesquisa na contribuição de dados para o fomento de uma legislação nacional que estabeleça valores limites de radioatividade para a comercialização e utilização de rochas graníticas, afim de atender, também, as normas internacionais que limitam o valor de radioatividade aceitável de produtos como mármores e granitos para a importação, exportação e trânsito. / Naturally occurring radionuclides such as radon (222Rn), its decay products and other elements from the radioactive series of uranium (238U and 235U) and thorium (232Th) are an important source of human exposure to natural radioactivity. Worldwide the evaluation of radiobiological effects and risks to health from exposure of the population to natural radionuclides is a growing concern. Elements such as radon (222Rn), the thoron (220Rn), radio (226Ra), thorium (232Th) and potassium (40K) can be found in materials commonly used in construction of houses and buildings. Thus, the radioactivity study from marbles and granites is important, given that under certain conditions these materials radioactivity levels can be hazardous requiring the implementation of mitigation measures for their use. This study presents a technical protocol for the control of human exposure to natural radioactivity from granitic rocks in marble factories. The protocol was based on measurements of the 222Rn and 220Rn concentration in Brazilian granite rocks commonly nationally and exported. The 222Rn and 220Rn measurements were done using the AlphaGUARD (Saphymo GmbH) and RAD7 (Durridge Company) equipment’s, respectively. For measures the samples of granite were sealed in glass jars for 40 days in order that the 226Ra and 222Rn radionuclides entered in secular equilibrium. The measurements were performed on Applied Nuclear Physics Laboratory at the Federal Technological University of Paraná. At the same time, solid-state nuclear track detectors CR-39 were installed in a marble factory environments located in Curitiba - Paraná for the evaluation of 222Rn concentrations in workplaces. The CR-39 detectors were exposed for about 90 days and submitted to etching process. The alpha particle tracks were observed using an optical microscope. The average 222Rn concentrations of granite samples ranged from 32 Bq/m3 to 1,7 KBq/m3. The results obtained underscore the importance of this research in the data contribution to the development of national legislation that establishes limits of radioactivity values for marketing and use of granitic rocks. The results also contribute to the Brazilian granite meets the international standards that limit the acceptable radioactivity value for the import, export and transit the products such as marble and granite.
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