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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.
401

Att bygga hållbara småhus som privatperson : En studie om materialval, kostnad och hinder

Dahlfors, Patricia, Näsström, Sofia January 2024 (has links)
Bygg- och fastighetssektorn representerade år 2021 21,7% av Sveriges inhemska utsläpp (Boverket, 2023a). Detta visar på en stor potential i branschen att minska klimat- och miljöpåverkan som går i linje med FN:s hållbarhetsmål. Företag arbetar aktivt med att bygga mer hållbart, men privatpersoner som bygger småhus har också möjlighet att bidra till en positiv förändring. Detta projekt syftar till att jämföra olika materialval i klimatskalet i småhus ur ett hållbarhetsperspektiv. Ett av de analyserade alternativen är ett befintligt nybyggt exempelhus (småhus A) med mindre vanliga materialval, som har jämförts mot ett konventionellt sätt att bygga svenska småhus på (småhus B) som framtagits genom en enkätundersökning. Frågorna i enkätundersökningen har baserats på befintlig litteratur om vanligt förekommande material som skickats till 53 byggföretag, varav 31 företag svarat. Ett egenutvecklat förslag (småhus C) har även tagits fram med målet att förbättra materialvalen ur ett ekonomiskt och miljömässigt perspektiv.   För att kunna utvärdera miljömässig hållbarhet har en livscykelanalys genomförts där utsläpp av koldioxidekvivalenter studerats under delar av bygg- och användningsskedet. Material- och transportkostnad har även analyserats ekonomiskt med hjälp av en livscykelkostnad. För att ett förslag ska vara hållbart måste den ekonomiska och miljömässiga aspekten balanseras, som kan uppnås om lösningen är miljövänlig samtidigt som den är ekonomisk försvarbar. Det egenutvecklade förslaget är baserat på resultatet av livscykelanalysen och livscykelkostnaden från småhus A och B, samt utefter befintliga hinder som undersökts genom litteratur och ett frågeformulär som skickats ut till några aktörer som är med och påverkar byggprocessen. Två fiktiva småhusmodeller som utgår från den genomsnittliga boarean av småhus i Sverige togs fram, som resultatet av studien applicerades på för att ge en uppfattning om totalt CO2eq utsläpp och kostnad för ett småhus.   Resultatet visade att småhus B är det billigaste alternativet, men även det som genererar störst koldioxidutsläpp. För 105 000 eller 124 000 kr mer för material- och transportkostnad för de framtagna fiktiva småhusen med area 122 kvm, kan 7,1 respektive 12,1 ton koldioxidekvivalenter sparas in om materialen i småhus C används i stället. Småhus A är mer miljövänligt sett till koldioxidutsläpp än småhus B men sämre än småhus C, och ekonomiskt mer kostsamt än både småhus B och C. Det material som är den största faktorn både ekonomiskt och miljömässigt är valet av isolering i vägg och tak. Resultatet från enkätundersökningen om vanliga materialval i svenska småhus visade att det verkar finnas en branschstandard för materialval i småhus. / 21,7 % of Swedens’s domestic emissions in 2021 was represented by the building an real estate sector (Boverket, 2023a), which highlights a considerable potential to reduce emissions in line with UN:s sustainability goals. As well as companies, individuals also have the opportunity to contribute to a positive change by building more sustainable houses. This project aims to compare different materials choices in the building envelope of houses from a sustainability perspective. One of the analyzed alternatives is an existing newly built example house (house A) built with less common materials, which was compared to a conventional Swedish house (house B) based on a conducted survey. A literature study of common existing materials were the foundation for survey, which was sent to 53 construction companies were 31 companies responded. An alternative proposition (house C) was developed during the project with the goal of improving material choices from both an economic and environmental perspective.   A life cycle analysis has been conducted to evaluate environmental sustainability by studying carbon dioxide equivalent emissions during material extraction and production, transportation, and the use stage. A life cycle cost assessment has been used to analyze material and transportation cost. The economic and environmental aspects must be balanced in order for a solution to be sustainable. This can be achieved if the solution is environmentally friendly while also being economically justifiable. House C is based on the results of the life cycle analysis and life cycle cost from house A and B, as well as existing obstacles that were examined through literature and questionnaire that was sent to involved stakeholders in the building process. Two fictional house models were creates based on the average living area of small houses in Sweden. The result of the study was applied to these models to provide an estimate of the total CO2eq emissions and cost for a small house.      The obtained results showed that the cheapest option is house B, but it also generates the highest carbon dioxide equivalent emissions. For an additional cost of 105 000 sek or 124 000 sek for the fictional houses with an area of 122 square meters, 7,1 and 12,1 tons of carbon dioxide equivalent emissions could be reduced if the material propositions for house C is used instead. House A is more environmentally friendly with regards to house B, but less so than house C. On the other hand, it is more expensive then both house B and C. The biggest factor is the choice of insulation materials in walls and the roof, regarding both the economic and environmental aspect. The result of the survey on common material choices in Swedish small houses indicates that there seems to be an industry standard for material choices on these houses.
402

Ekologiškų namų racionalaus varianto intelektinės sistemos kūrimas / Development of an Intelligent System for Rational Variant of Eco-friendly Houses

Verikas, Vaidas 01 July 2011 (has links)
Baigiamajame magistro darbe nagrinėjamos ekologiškos statybinės medžiagos, analizuojami namo dalių konstrukciniai variantai, statant namus iš šių medžiagų. Taip pat sudaroma kompiuterinė sistema, padedanti vartotojui išsirinkti racionaliausią ekologiškų medžiagų panaudojimo variantą. Darbą sudaro trys dalys. Pirmojoje dalyje apžvelgiama ekologiškų statybinių medžiagų samprata, pagrindiniai principai, aprašomas statybinių medžiagų gyvavimo ciklas, aptariama aplinkai nekenksmingų medžiagų situacija Europoje. Antrojoje dalyje plačiau aprašomos gamtai nekenksmingos statybinės medžiagos, galimi tokių medžiagų konstrukciniai variantai. Analizuojami sienų, stogo dangos, šilumos izoliacijos ir šildymo sistemos pritaikymo galimybės statant ekologišką namą. Trečiojoje dalyje nagrinėjamas praktinis ekologiško namo konstrukcijų pritaikymo modelis. Sudaroma alternatyvų ir kriterijų sistema, apibūdinanti nekenksmingo aplinkai namo konstrukcinius elementus. Panaudojant kiekybinius ir kokybinius kriterijus ir galimas medžiagų alternatyvas, atliekama daugiakriterė statybinių medžiagų ir jų konstrukcijų analizė, sudaroma kompiuterinė sistema. / Ecological and environmentally friendly building materials and constructional options, that are used to build houses, are considered in this master work. It also contains the computer system enabling the user to choose the most rational option of ecological materials. This master work consists of three parts: In the first part the concept of ecological building materials and main principles are described. It also contains information about the life cycle of building materials and the situation of environmentally friendly materials in Europe are discussed. The second part describes environmentally friendly building materials and possible structural variations of such materials. It analyzes walls, roof, heat insulation and possibilities of heating system in the ecological house. In the third part the practical model of the ecological house is considered. An alternative and criteria system that describes the environmentally friendly house constructional elements is created. Using quantitative, qualitative criteria and possible material alternatives multiple criteria analysis of building materials and their construction is performed. The computer system is also made.
403

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 waste

Hackbart, 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%.
404

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 waste

Hackbart, 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%.
405

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 practices

Ghyoot, 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
406

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 material

Lošáková, 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.
407

Energy efficiency interventions for residential buildings in Bloemfontein using passive energy techniques

Kumirai, 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.
408

Rural housing and rural development in Northern Namibia

Wienecke, 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)
409

An investigation into the time and cost factors for a decision between in-situ and hybrid concrete construction

Piek, 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.
410

Compósito cimento-lodo de ETE de indústria de papel para aplicação na construção civil / Composite cement-sludge from pulp and paper industry mills effluent treatment for use in building materials

Paiva, Samantha Nazaré de 26 April 2007 (has links)
O grande volume de resíduos sólidos industriais gerado pelo setor de celulose e papel e o alto custo do seu manejo estimulam pesquisas em busca de soluções mais adequadas para o seu gerenciamento. Uma alternativa que se destaca neste contexto é o aproveitamento destes resíduos em materiais de construção. Este trabalho visa o aproveitamento do lodo de ETE de indústria de papel na produção de compósitos cimentícios para uso na construção civil. Foi estudada a influência de diferentes teores da adição do lodo de ETE (5%,10%,20% e 30% em massa) em argamassa de cimento e areia, com relação água-cimento de 0,65. Determinou-se para o resíduo: teor de umidade; massa unitária; massa específica; pH; sazonalidade de geração e teor de sólidos fixos e para o compósito: massa específica aparente; absorção de água por imersão; absorção de água por capilaridade; retratibilidade; isolamento acústico; resistência à compressão e análise da microestrutura. O resíduo foi classificado como Classe II &#150; A, não inerte e não perigoso, o que indica alto potencial para aproveitamento em materiais de construção. Sua incorporação na argamassa aumentou a absorção de água por capilaridade em 12,76 % e por imersão em 18,93% no traço com 30% de resíduo para a empresa &#34;A&#34;. Houve também a diminuição da resistência à compressão com a incorporação do resíduo, entretanto definiu-se o ponto-ótimo de incorporação em 12% para as duas empresas avaliadas, garantindo assim a resistência mínima à compressão de 2,5 MPa, exigência para blocos sem função estrutural. A incorporação de resíduo também apresentou decréscimo na massa específica do compósito de 14% na empresa &#34;A&#34; e de 34% para a empresa &#34;B&#34; para os traços de 30% de resíduo. Os resultados permitem concluir que este compósito é adequado para uso em materiais de construção sem função estrutural. / The large volume of industrial solids residues generated by the pulp and paper sectors and its high management cost stimulate research aiming at finding adequate solutions to its management. An alternative that shows high potential in this context is using these residues in building materials. This work aims at studying the use of paper&#39;s mills effluent treatment solid waste in the production of cement composites to be used in construction. The influence of adding different sludge proportions (5%,10%,20% and 30% in mass) in cement and sand mortar, with a water-cement relation of 0,65 was studied. The humidity ratio, unit mass, specific mass, pH, generation season and fixed solid concentration for the residue; and specific apparent mass, water absorption by immersion, water absorption by capillarity, acoustic isolation, compression resistance and microstructure analysis for the composite. The residue was classifies as Class II &#150; A, not inert and not dangerous, which indicated high potential for use as building materials. Its use in the mortar increased the water absorption by capillarity in 12.76% and in immersion by 18.93% in the trace of 30% residue from company &#34;A&#34;. There was also a decrease in compression strength when the residue was incorporated, however the optimal incorporation point was defined in 12% for both evaluated firms, guaranteeing the minimum compression resistance of 2.5 MPa, required for block without structural function. The residue incorporation also presented a decrease in the composite specific mass of 34% for company &#34;B&#34; and 1% for company &#34;A&#34; for the traces of 30% residue. The results allow us to conclude that this composite is adequate for use as building materials with no structural function.

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