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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.
61

Percepções relativas às práticas em sustentabilidade nos canteiros de obras

Coutinho, Sandra Lúcia Moscon 06 September 2013 (has links)
Made available in DSpace on 2016-12-23T14:05:53Z (GMT). No. of bitstreams: 1 Sandra Lucia Moscon Coutinho.pdf: 5557407 bytes, checksum: e4912c06f06201eb877dbb2827c4d8bf (MD5) Previous issue date: 2013-09-06 / A construção civil destaca-se por ser uma atividade causadora de grandes impactos ao meio ambiente em função de seu elevado consumo de recursos materiais naturais, água e energia, e altos índices de resíduos e poluições gerados. Em contrapartida, apresenta significativa importância econômica e desafios a serem vencidos: desenvolvimento de maneira sustentável, evitando danos ambientais irreparáveis às futuras gerações. A sustentabilidade deve ser inserida em todo o ciclo de vida da edificação, em especial no seu início, ou seja, na fase de canteiros de obras, pois é nesta fase que ocorre grande parte dos impactos ambientais. Neste contexto, esta pesquisa de caráter descritivo e qualitativo, apresenta um instrumento de avaliação de percepções relativas às práticas em sustentabilidade para a fase de canteiro de obras, composto de: (a) questionário; (b) lista de observações diretas e (c) lista para registro fotográfico. Foram realizados nove estudos de caso em canteiros de obras de edificações, localizados na cidade de Vitória (ES), para aplicar o instrumento proposto. A aplicação do instrumento de avaliação despertou interesse por parte dos responsáveis pelos canteiros de obras, possivelmente por ser este tema ainda pouco discutido no mercado local. Observou-se que, sob a ótica das percepções dos entrevistados, a sustentabilidade nos canteiros de obras, ocorre de forma incipiente, apesar de os canteiros visitados, pertencerem a empresas construtoras de médio e grande porte, com certificações da série ISO 9001, PBQP-H nível A e possuírem diversos empreendimentos construídos e em construção / The civil engineering process stands out for being an activity whitch causes major impact to the environment, due to its high consumption of material resources, water and energy, and its high levels of waste and pollution generation. On the other hand, it has significant economic importance and challenges to overcome: like sustainable development, in order to avoid irreparable environmental harm to future generations.Sustainability shoud be inserted throughout the buildinglife cycle, specially in its beginning, whitch means, in the construction site phase, because it is here where occur most of the environmental impacts. In this context, this descriptiveand qualitative research, presents an assessment instrument of perceptions regarding sustainability practices for the construction site phase, consisting of: (a) questionnaire; (b) direct observations list; and (c) photographic records list. The proposed assessment tool was applied to nine case studies, conducted on construction sites, located in the city of Vitória (ES). The application of the assessment instrument aroused interest among those responsible for the construction sites, possibly because this topic is little discussed in the local market. It was observed that, from the perspective of the respondent perceptions, sustainability in the construction site phase is in an incipient form, even though the construction sites visited belongto builders of medium and large sizes, with ISO 9001 certifications, PBQP-H level A and a lot of finalized and under construction buildings
62

Práticas recomendadas para a gestão mais sustentável de canteiros de obras. / Recommendable practices for more sustainable siteworks management.

Viviane Miranda Araújo 20 August 2009 (has links)
A construção sustentável é uma condição essencial para o alcance do desenvolvimento sustentável da sociedade. Para isso, é necessário preocupar-se com a sustentabilidade de todas as etapas do ciclo de vida de um empreendimento, desde sua concepção, passando pelo projeto, construção, manutenção, até sua demolição, considerando sempre as três dimensões da sustentabilidade: econômica, social e ambiental. Portanto, destaca-se o estudo da redução dos impactos negativos da etapa de construção de empreendimentos na medida em que a indústria da construção civil, além de grande consumidora de recursos naturais, é fonte de diversos impactos negativos causados ao meio ambiente. Dessa forma, o objetivo desta pesquisa é propor práticas a serem adotadas por empreendedores e empresas construtoras e seus subcontratados em seus canteiros de obras, visando a um processo de produção de edifícios mais sustentável em áreas urbanas. Essas práticas envolvem diretrizes tecnológicas e gerenciais, além de um guia, que propõe uma estratégia para implantação de canteiros de obras mais sustentáveis. A pesquisa, de propósito exploratório e caráter qualitativo, foi desenvolvida por meio de estudos teóricos, envolvendo revisão bibliográfica nacional e internacional, assim como observações em campo. Como principais resultados, apresentam-se: a evolução da matriz de correlação de aspectos e impactos ambientais de canteiros de obras de edifícios; a formulação de conjunto de diretrizes tecnológicas e gerenciais que visem a um processo de produção mais sustentável em canteiros de obras; e a elaboração de um guia para implantação de um canteiro de obras mais sustentável. / Sustainable construction is an essential condition for society sustainable development achievement. So, concerning about sustainability is indispensable for all stages of the building life cycle, since its conception, through design, construction, maintenance, until its demolition, considering the three dimensions of sustainability: economical, social and environmental. Hence, the building construction negative impacts reduction study stands out, as the construction industry, besides being a great consumer of natural resources, causes unwanted environmental impacts. Thus, the purpose of the research is to provide recommendable practices to be adopted by the constructors in their site works, aiming at a more sustainable production process in urban areas. These practices involve technological and managerial guidelines, besides a guide, which proposes a more sustainable site works establishment strategy. The research has exploratory object and qualitative nature, and was developed through theoretical studies, involving national and international literature review, and field observations. As main results there are: the evolution of the site works environmental aspects and impacts correlation matrix, the formulation of technological and managerial guidelines aiming at a more sustainable site works production process, and the preparation of a guide for a more sustainable site works establishment.
63

CORPORATE SOCIAL RESPONSIBILITY  COMMUNICATION from a NETWORK PERSPECTIVE : A Case Study of Peab AB

Chuikina, Viktoriya, Ekberg-Tamminen, Sari January 2012 (has links)
Problem Description: Since there are recognized similarities in the construction industry between relationship building and strategic CSR engaging thus managing and communicating CSR should be evaluated from the industrial network perspective. Close interaction between stakeholders and implemented strategic CSR facilitate to perform successfully and remain competitive when facing challenges in modern construction industry. Peab AB was chosen for the research as one of the leading construction companies in the Nordic region that recently redefined its CSR strategy and now delivering and sharing the vision through entire established network. Purpose of the research: Sustainable development has become part of the business plans for Swedish construction companies. Therefore it is relevant to research implementation of sustainable dynamics in the Peab’s vision by analyzing their strategic CSR process and how it is communicated to their key stakeholders within complex industrial network. Research questions: How is sustainability vision and strategic CSR communicated through Peab’s business relationships within its industrial network? How does the company communicate its CSR strategy within the industrial network? How does the company handle its CSR issues within long-term relationships? Methods: In this thesis qualitative research method with deductive approach has been used. The empirical findings contain primary data such as interviews with the management of the Peab Group, Peab Grundläggning, Swerock and Leimet. The secondary data sources were academical journals, books, Peab website and its corporate policy, annual & sustainability reports. Conclusion: By combining traditional industrial marketing theories together with the modern strategic CSR communication, it has been concluded that the sustainability vision and strategic CSR engaged and communicated to the stakeholders through Peab’s industrial network have process kind of nature.  Even though sustainability vision helps Peab to remain successful and competitive in the long run their performance in the industrial network depends highly on close cooperation with the stakeholders. Close interaction and committed relations with partners is one of the ways of handling sustainability aspects in the construction industry.
64

Understanding the issues of project cost and time in sustainable construction from a general contractor's perspective: case study

Weeks, Jason A. 17 March 2010 (has links)
The green building market has seen tremendous growth in the past decade. Organizations such as the US Green Building Council have emerged to become a dominant leader in the building industry. Although the green building rating systems are cross-disciplinary, much of the focus has been directed towards design-related input. General Contractors play an important role in delivering successful sustainable construction projects. If an integrated project delivery method is chosen, the General Contractor may offer insightful preconstruction assistance by providing ideas on green construction methods and materials. As sustainable building practices become more prominent in the construction industry, General Contractors must remain knowledgeable on current green building standards in order to stay competitive. Two of the most important aspects of business for a General Contractor involve time and money. Through qualitative literature review and quantitative results from a case study, this research analyzes time and cost in sustainable construction projects from a General Contractor's perspective. The research also examines whether the management of a sustainable construction project is substantially different than a non-sustainable construction project for a General Contractor. Finally, because the green building process involves multiple parties, the collaboration effort from all parties involved in a green building project will be studied.
65

Structural behaviour and optimization of moment-shaped reinforced concrete beams

Hashemian, Fariborz 25 July 2012 (has links)
This research includes a preliminary study prior to the commencement of the Ph.D. work and three phases of design, construction and testing of three generations of moment-shaped beams. Each phase of the research brought a better understanding of curved beams which follow the shape of the moment diagram. The moment diagram in this study was for simply supported beams supporting a uniformly distributed load as would be the case in the majority of building designs. The original theory for this research can be described as follows: Moment-shaped beams are the natural outcome of a fundamental understanding of stress paths in a horizontal load bearing member. By following these stress paths we may provide materials where required to most efficiently carry the compression and tension stresses to the supports. Allowing stresses to follow their naturally desired paths reduces regions where stresses cross paths called disturbed regions. The outcome of the final phase of this research was the development of the third generation of curved beams with a camber. These beams, designated as Cambered Curve beams (CCBs), exhibited the same behaviour as the rectangular control beam design using CSA-A23.3 up to the serviceability failure of L/360 (12mm). The CCB moment-shaped beams require 20% less concrete and 40% less reinforcing steel (no shear stirrups) to carry the ultimate load which is only 12% less than that carried by the CSA-designed control beam. Due to a closed system of internal forces, the moment-shaped beams remain intact and are able to sustain self weight, even after total failure. A significant part of this research was to modify and verify a FORTRAN-based finite element analysis program: FINIT-Y. This program was reconstructed to analyse a full size beam, and enabled the researcher to model and correctly predict the maximum load, crack pattern and failure mode. This study found that moment-shaped beams with no shear reinforcement have the same stiffness and load carrying capacity as the CSA-designed rectangular control beam with shear reinforcement up to serviceability failure (L/360). The study also found that moment-shaped beams have significantly lower ductility at the ultimate load.
66

Structural behaviour and optimization of moment-shaped reinforced concrete beams

Hashemian, Fariborz 25 July 2012 (has links)
This research includes a preliminary study prior to the commencement of the Ph.D. work and three phases of design, construction and testing of three generations of moment-shaped beams. Each phase of the research brought a better understanding of curved beams which follow the shape of the moment diagram. The moment diagram in this study was for simply supported beams supporting a uniformly distributed load as would be the case in the majority of building designs. The original theory for this research can be described as follows: Moment-shaped beams are the natural outcome of a fundamental understanding of stress paths in a horizontal load bearing member. By following these stress paths we may provide materials where required to most efficiently carry the compression and tension stresses to the supports. Allowing stresses to follow their naturally desired paths reduces regions where stresses cross paths called disturbed regions. The outcome of the final phase of this research was the development of the third generation of curved beams with a camber. These beams, designated as Cambered Curve beams (CCBs), exhibited the same behaviour as the rectangular control beam design using CSA-A23.3 up to the serviceability failure of L/360 (12mm). The CCB moment-shaped beams require 20% less concrete and 40% less reinforcing steel (no shear stirrups) to carry the ultimate load which is only 12% less than that carried by the CSA-designed control beam. Due to a closed system of internal forces, the moment-shaped beams remain intact and are able to sustain self weight, even after total failure. A significant part of this research was to modify and verify a FORTRAN-based finite element analysis program: FINIT-Y. This program was reconstructed to analyse a full size beam, and enabled the researcher to model and correctly predict the maximum load, crack pattern and failure mode. This study found that moment-shaped beams with no shear reinforcement have the same stiffness and load carrying capacity as the CSA-designed rectangular control beam with shear reinforcement up to serviceability failure (L/360). The study also found that moment-shaped beams have significantly lower ductility at the ultimate load.
67

Buying into residential eco-estates: perception and reality of "green living" in eco-estates in Gauteng, South Africa

Sherriff-Shuping, Roselle Danette January 2015 (has links)
With few studies focusing on the construction of green buildings in South Africa, there is a need to understand the reasoning behind the development of residential estates that have classified themselves as “eco”. The aim of this study was to establish whether or not residential estates that market themselves as “eco” are in fact sustainable. This study looks at the environmental sustainability of residential eco-estates (n=7) and compares them to non-eco-estates (n=7) in the Gauteng Province of South Africa. The study used content analysis to evaluate the marketing material of the 14 estates sampled for the study. The data gathered through content analysis was then used to determine the environmental sustainability for each estate using an adapted version of the Sustainable Building Assessment Tool. The findings indicate that although the residential eco-estates had higher environmental sustainability scores when compared with non-eco-estates, the overall score for many of the eco-estates was too low for them to be classified as sustainable. The results of the study also highlight that a number of the eco-estates use greenwashing methods to attract potential homeowners. By selling nature, these estates are able to attract homeowners who may be interested in protecting the environment. When looking at these findings, it is possible to assume that the development of residential eco-estates has less to do with the sustainability of nature and has more to do with a desire to increase profits. In order to achieve environmental sustainability, it is therefore important to provide guidelines for developers to use if they are genuinely interested in creating estates that focus on the protection of the environment and natural resources. These guidelines can be developed through frameworks that exist to evaluate the sustainability of developments. Although much of the focus of this research is placed on the developers of each estate, it is important to acknowledge that the individuals who live within these estates are just as responsible for achieving sustainability. / Geography / M.A. (Geography)
68

Elementos construtivos e de proteção térmica à base de gesso e resíduos agroindustriais

Noronha, Livia Lima 14 August 2014 (has links)
Made available in DSpace on 2015-05-14T12:09:40Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3962338 bytes, checksum: 03f9aed8a56ba7c74bc692ad2af0238f (MD5) Previous issue date: 2014-08-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The sustainable construction concept has attracted attention worldwide, seeing that already is against scarcity of natural resources and energy, solid waste generation and emission of gases that damage the planet increasingly. This study invetigated the possibility the use of vegetable fibers pseudostem of banana and pulp packaging of cement for the development of composites that stand out for its reinforcing properties and thermal. The use of renewable materials can help reduce the strain on the environment. Packages of Portland cement are in Kraft paper and the vast majority are discarded into the environment. However, as they contain pulp fibers (cellulose) can be used as reinforcement in matrix. To obtain the pulp coming from cement bags, they were cut into pieces and passed in a paper shredder. Then the crushed material was immersed in water and passed on an industrial blender. In mixtures prepared with the fiber banana fiber percentages of 2% and 4% and the water / gypsum ranging from 0.4 to 0.7 were tested. The trace with 4% fiber and the water / plaster 0.5 resulted in a resistance of 2.80 MPa, while the mark with 2 % fiber and 0.4 of the water / gypsum produced a composite resistor 5 , 87 MPa. It is observed that by reducing the amount of fiber in the composite and the water / plaster, resistance increased due to voids also decreased . For the optimization of mixtures made with the pulp ranged up the water / plaster. The features were always molded to a ratio of 1 kg of gypsum / 0.08 kg pulp / 0.01 retardant additive. The variation of the water / gypsum was tested to get the best strength and workability. The best water / plaster ratio is 0.7. The results obtained by the method of hot plate protected, we found good results mainly the thermal properties of composites prepared with plaster and pulp packaging of cement. The test of thermal conductivity of the composite using the hot plate method showed that decreased compared to the plaster without reinforcement. / O conceitoconstruçãosustentável tem despertado a atenção em todo o mundo, visto que já se está diante da escassez de recursos naturais e de energia, geração de resíduos sólidos e emissão de gases que danificam cada vez mais o Planeta. Este estudo investigou a possibilidade do uso de fibras vegetais do pseudocaule da bananeira e polpa de embalagens de cimento para o desenvolvimento de compósitos que se destacam por suas propriedades de reforço e térmicas.O aproveitamento de materiais renováveis pode ajudar a reduzir as agressões ao meio ambiente. As embalagens de cimento Portland são em papel tipo Kraft e na sua grande maioriasão descartadas no meio ambiente. No entanto, elas contêm fibras na forma de polpa (celulose) que podem ser utilizadas como reforço em matrizes. Para a obtenção da polpa oriunda de sacos de cimento, estes foram cortados em pedaços e passados em um triturador de papel. Em seguida o material triturado era imerso em água e passado em liquidificador industrial. Nas misturas elaboradas com a fibra de bananeira foram testadas porcentagens da fibra em 2% e 4% e relação água/gesso variando de 0,4 a 0,7. O traço com 4% de fibra e relação água/gesso 0,5 conduziu a uma resistência de 2,80 MPa, enquanto que o traço com 2% de fibra e 0,4 de relação água/gesso produziu um compósito com resistência de 5,87 MPa. Observa-se que ao diminuir a proporção de fibra no compósito e a relação água/gesso, a resistência aumentou devido aos vazios que também diminuíram. Para a otimização das misturas realizadas com a polpa variou-se relação água/gesso. Os traços foram moldados sempre para a proporção de 1 kg de gesso/0,08 kg da polpa /0,01 do aditivo retardador. A variação da relação água/gesso foi testada até se chegar nas melhores resistência e trabalhabilidade. A melhor relação água/gesso é de 0,7. Através dos resultados obtidos pelo método de placa quente protegida, constatou-se bons resultados das propriedades térmicas principalmente dos compósitos elaborados com gesso e polpa de embalagens de cimento. O teste de condutividade térmica do compósito utilizando o método da placa quente mostrou que houve redução em relação ao gesso sem reforço.
69

Gestão sustentável para área contaminada em campus universitário / Sustainable management of a contaminated area on campus

Fernanda Bertaco Bueno 12 June 2017 (has links)
A presença de contaminação por substâncias perigosas no solo e na água subterrânea acarreta inúmeros problemas, tais como: risco à saúde humana e aos ecossistemas; comprometimento da água para abastecimento público; e redução do valor econômico e da função social do terreno. Embora as tecnologias de remediação sejam aplicadas para resolver problemas ambientais e de saúde pública, estas também podem gerar externalidades ambientais negativas como consumo de energia e recursos naturais; desequilíbrio do ciclo da água; erosão do solo; e emissão de gases de efeito estufa. Tendo em vista a recente ocorrência com áreas contaminadas na Universidade de São Paulo (USP) o presente trabalho visou elaborar um plano de gestão sustentável para uma dessas áreas localizada no campus USP da Capital, contribuindo com o Programa de Políticas Ambientais, sob coordenação da Superintendência de Gestão Ambiental da USP. A metodologia de pesquisa foi baseada em revisão bibliográfica sobre remediação sustentável e construção sustentável e em a análise qualitativa das ações, práticas e lições aprendidas de casos bem sucedidos de gestão das áreas contaminadas com elementos sustentáveis como subsídio para elaboração do plano. A partir da caracterização de quatro áreas contaminadas existentes no campus USP da Capital, foi selecionada a área da USP Leste para estudo de caso para promover o uso de práticas sustentáveis em campus universitário, de tal forma que proteja a saúde humana e minimize os impactos ambientais adversos. Com o intuito de buscar melhorias à gestão do campus, por meio da inserção da sustentabilidade na gestão da contaminação da USP Leste, a elaboração do plano de gestão sustentável considerou as especificidades locais nas práticas sustentáveis a serem implementadas, conforme as necessidades e diretrizes da USP. As soluções propostas incluíram a combinação do planejamento das fases de investigação e remediação com o design da construção de edifícios, que possam trazer benefícios ambientais, econômicos e sociais a todas as partes interessadas, tais como redução de custos a longo prazo relacionados à redução do consumo de energia e eletricidade pela implantação de sistemas de energia renováveis para fornecimento de energia elétrica ao sistemas de ventilação de metano / The presence of contamination by hazardous substances in soil and groundwater causes numerous problems, such as risk to human health and ecosystems; water impairment as drinking water; and reduced economic value and social function of the land. Although remediation technologies solve environmental and public health issues, they can also generate negative environmental externalities such as energy and natural resources consumption; imbalance of water cycle; soil erosion; and greenhouse gas emissions. Due to recent occurrence with contaminated areas at the University of São Paulo (USP) the present work aims to develop a sustainable management plan for one of these areas located on the USP Capital campus, contributing to Program of Environmental Policies, coordinated by the Superintendence of Environmental Management of USP. The research methodology was based on literature review about sustainable remediation and construction; and qualitative analysis of actions, practices and lessons learned applied on successful case studies of contaminated sites management with sustainable elements as subsidy for elaboration of the plan. Based upon a characterization of four contaminated areas located on USP Capital campus, the site of USP Leste was selected as case study in order to promote the use of sustainable practices on campus, through an approach that protects human health and minimizes adverse environmental impacts. In order to seek improvements to the campus management by sustainability integration in contamination management of USP Leste, the elaboration of sustainable management plan considered local specificities on sustainable practices to be implemented, according to the needs and guidelines of USP. The proposed solutions included the planning of investigation and remediation stages with the construction design of buildings that can bring environmental, economic and social benefits to all stakeholders, such as long-term cost savings related to the reduction of energy consumption and electricity by the implementation of renewable energy systems to supply electricity to methane ventilation systems
70

Compensação ambiental de canteiros de obras em ambientes urbanos: um foco no meio antrópico. / Building sites environmental compensations in urban areas: focusing the anthropic environment.

Viviane Miranda Araujo Fiorani 21 June 2016 (has links)
O alcance do desenvolvimento sustentável, envolvendo as dimensões ambiental, social e econômica, é um desafio reconhecido mundialmente, sendo a construção sustentável uma condição essencial para o seu cumprimento. Dessa forma, uma importante ação é a diminuição dos impactos ambientais da construção civil, com a implantação de políticas voltadas à redução na sua própria geração. Observa-se, porém, que nem sempre os impactos podem ser reduzidos na origem. Sugere-se, assim, a adoção de medidas compensatórias que contrabalanceiem os prejuízos gerados, de modo a restabelecer as condições ambientais existentes antes dos impactos. O objetivo desta pesquisa, portanto, é a elaboração de uma proposta para a compensação dos impactos ambientais de canteiros de obras de edifícios em áreas urbanas, observando o meio antrópico. O estudo é conduzido em duas etapas: embasamento teórico, que envolve revisão bibliográfica nacional e internacional; e elaboração da proposta para a compensação ambiental. Esta tese apresenta um método de cálculo composto por quatro indicadores: ruídos, emissão de material particulado, danos a bens edificados e ocupação da via pública. Esses, por meio da adoção de Fatores de Ponderação, têm sua relevância graduada de acordo com o meio ambiente em que o canteiro está inserido. Tais fatores são calculados com o auxílio de questionários formulados para identificar as necessidades locais e aplicados à vizinhança da obra. Por fim, o cálculo resulta em um valor que, variando de 0 a 10, determina o grau de compensação necessário para cada obra. Discute-se, então, as maneiras de transformar o valor calculado em uma compensação efetiva, assim como formas de realizar a fiscalização de sua implantação. / The success of sustainable development, universally recognized regarding the economic, environmental and social limitations it incorporates, is primarily dependent on sustainable construction. Being so, the reduction of environmental impacts by implementing effective policies during initial construction operations becomes all important, although not always possible. Compensatory measures are therefore proposed to minimize and counterbalance the losses incurred and restore the environmental conditions existing prior to impact. In concurrence, this research aims to elaborate a course of action which will compensate for impacts produced at building construction sites in urban areas by strict observance of the anthropic environment. This study comprises two phases: a theoretical basis covering a review of national and international references; and the elaboration of a proposal for environmental compensation. Also presented is a method of calculation using four indicators: noises, particulate matter emissions, damage to buildings and the utilization of public streets. Weighed factors, considering building site location, are used to give a graduated relevance to each indicator. These factors are calculated with the aid of questionnaires that seek to identify local necessities and applied to the neighborhood surrounding the site. As a result, the method produces a value ranging from 0 to 10 which determines the degree of compensation each project warrants. This calculated value is then discussed, with the objective of transforming it into effective compensation and discovering ways of supervising its implementation.

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