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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.
21

Moderní jednotka pro energetické využití odpadů o střední kapacitě / Up-to-Date Medium Capacity Waste-to-Energy Unit

Krišpín, Jan January 2017 (has links)
The submitted Master Thesis deals with the technological/mechanical solution of an up-to-date medium capacity waste-to-energy plant. Operational requirements and basic parameters related to a concrete region are specified in the introduction of the Thesis. This is supplemented by a flow-sheet of the plant with the description of main process subsystems. To meet the goals of the Thesis basic balance information is summarized and related schemes included. These data represent principal inputs for the on-site plant as well as basic parameters for the design of key equipment. These pieces of equipment are schematically drawn including their basic parameters and a description of construction. All the available innovative solutions are taken into account. The Thesis provides also a technical-economic analysis for being able to evaluate the overall project.
22

Blandat byggavfall : Vägen mot en miljömässig hållbar avfallshantering / Mixed construction waste : The path to environmentally sustainable waste management

Stenmark, Maja January 2022 (has links)
Construction of new buildings and restoration of existing buildings is causing waste. Often,the waste consists of a mixture of different materials, also called “mixed waste”. Waste fromconstruction sites stands for over 35 % of the entirely waste in amount Sweden and is aconsiderable contributing factor to the carbon dioxide emissions. It is very important that theamount of waste is reduced, and different materials are separated in order to achieve increasedsustainability. This report will examine the alternatives for building companies to minimisethe mixed waste fraction from their construction sites, using waste statistics from constructionprojects in the northern part of Sweden and a survey answered from the site managers at theconstruction company. The results show that mixed waste is one of the largest fractions ofwaste from construction projects, and it is also one of the most expensive fractions. Theenvironmental benefits and the economic gain a reduced mixed waste can contribute with, isan important step to reduce the climate impact from construction work. This paper willhopefully inspire some new ideas for minimising the mixed waste fraction at constructionproject, for example the displaying of containers for the different waste fractions. To separatethe different waste fractions efficiently and is beneficial regarding the environmental impactand the economy of the building companies.
23

Ökad källsortering för materialåtervinning : Åtgärdsförslag för att minska mängden byggavfall som källsorteras i fraktionen brännbart

Langborg, Julia, Tavana Nejad, Frida January 2020 (has links)
There is a great need for reducing the extraction of limited resources of the Earth today. Oneway to achieve this, inter alia, is through increased recycling of material. The UN is activelytaking action on the matter, on a global level, and regionally the European Union hasdeveloped a directive on material waste. The Swedish construction sector is responsible forapproximately a third of the total generated waste, and measures regarding construction wasteshould thus be prioritized. Based on the abovementioned EU directive, the SwedishEnvironmental Protection Agency has developed a national action plan for waste, in whichconstruction and demolition waste is a focal point. JM AB is one of the leading corporationsin the Nordic countries in terms of housing development projects and one of their keyconcepts is sustainability. Not only does JM conduct its work in accordance with the currentrecommendations of both national and regional bodies, but in addition it has raised theambitions even further.JM is actively working to reduce the amount of landfill waste as well as the total amount ofwaste, and it has a good structure in place for doing so. An area of improvement with recyclingthat has now been identified is separation at source of combustible waste. Materials such aswood, plastics and corrugated cardboard can be separated from other combustible materials.This would not only increase the waste being recycled but also decrease the waste being burntfor energy extraction. The purpose of this thesis is to examine obstacles and possibilitieswithin the current recycling of combustible waste. The main ambition is for the results toprovide a foundation for the work of JM with regards to this, but hopefully other corporationsand actors within the construction sector will find the results useful and helpful as well.An internal survey was conducted and the questionnaire included both open questions andquestions with multiple-choice answers. Six employees at JM also participated in interviews.For added depth and more thorough analysis two waste contractors were also interviewed.Furthermore, a literature review was conducted and suggested that there is a strong need forchange in recycling within the entire construction sector. The review also showed that manysimilar problems exist in other construction companies.The survey, literature review and interviews lead to several action proposals of varying extentand complexity. Some of them are more specific, such as clearer signage on containers, newtank solutions, introduction of recycling instructions, and focus on recycling of wrappingplastics. Other proposals respond to more complex issues, such as a lack of commitment andsubstandard planning in the initial stages. What increases dedication and commitment is veryspecific for each individual. A shift in behavior relative to recycling, as well as increasedknowledge of combustibles, are both necessary. For this to happen a continuous effort isrequired, which in and of itself is a challenge, as well as clear leadership, division ofresponsibilities, and top down support within the corporate group.In a broader perspective, better cooperation from all actors within the construction sector isnecessary. An increased producer responsibility overall is required and improvements inwaste management alone is not sufficient. Producers should ensure that products andwrapping can be reused or recycled. This requires better and easier access to recycling, butalso a viable market for recycled material, and by extension manufacturers should be obligedto use more recycled material in their products.
24

Utilização de veículo aéreo não tripulado (VANT) na identificação de resíduos de construção civil (RCC) dispostos em locais inadequados

Parente, Dênis Cardoso 09 November 2016 (has links)
Existe um número considerável de áreas utilizadas como pontos de descarte de resíduos de construção civil na cidade de Palmas – TO que extrapolam o alcance das ferramentas de controle e fiscalização do município, principalmente em pontos dentro do perímetro urbano. A presente pesquisa tem como objetivo principal verificar a aplicabilidade da utilização de imagens obtidas pelo veículo aéreo não tripulado (VANT), no auxílio da identificação dos resíduos e de pontos de descarte de resíduos de construção civil (RCC) em áreas irregulares da cidade. De posse do instrumento, foram tomadas como unidade amostral áreas de descarte preliminarmente mapeadas por meio de imagens de satélite com resoluções espaciais menos refinadas. Com metodologia que permitisse atestar a potencialidade dos produtos gerados em termos de fotointerpretação, precisões geométricas e geográficas, foram feitos sobrevoos com diferentes sobreposições de imageamento e com a utilização de pontos de controle coletados por meio de GPS de precisão. Os resultados encontrados mostram que as imagens aéreas obtidas e os ortomosaicos gerados podem auxiliar de forma confiável, rápida, segura e com melhores informações na identificação de pontos de lançamento de RCC, atestando que as plataformas VANTs e os sensores passíveis de serem acoplados à elas podem servir adequadamente como tecnologia para sensoriamento remoto, como ênfase no estudo proposto. / There are a considerable number of areas used as waste disposal points for construction in the city of Palmas - TO, which extrapolate the reach of the control and inspection tools of the municipality, especially in points within the urban perimeter. The present research has as main objective to verify the applicability of the use of images obtained by the unmanned aerial vehicle (UAV), in the aid of the identification of the residues and points of disposal of construction waste (RCC) in irregular areas of the city. Once the instrument was in possession, preliminary sampling areas were mapped using satellite images with less refined spatial resolution. With a methodology that allowed to attest to the potential of the products generated in terms of photointerpretation, geometric and geographic precisions, overflight with different overlays of imaging and with the use of control points collected through precision GPS were made. The results obtained show that the aerial images obtained and the generated ortomosaic can help in a reliable, fast, safe and with better information in the identification of points of launch of RCC, attesting that the platforms VANTs and the sensors that can be coupled to them can Adequately serve as a technology for remote sensing, as an emphasis on the proposed study.
25

Durabilidade de concretos com agregados reciclados / Durability of concrete with recycled aggregate

Rizzo, Giovanna Falzetta 26 February 2018 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2018-04-10T19:01:59Z No. of bitstreams: 1 GIOVANNA FALZETTA RIZZO.pdf: 4328364 bytes, checksum: c9d6f46d59c6df71381b35bbaab4f27e (MD5) / Made available in DSpace on 2018-04-10T19:01:59Z (GMT). No. of bitstreams: 1 GIOVANNA FALZETTA RIZZO.pdf: 4328364 bytes, checksum: c9d6f46d59c6df71381b35bbaab4f27e (MD5) Previous issue date: 2018-02-26 / Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo - FAPESP / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Civil construction is one of the industries that most impact the environment. The extraction of natural resources, the cement production, the concrete production and the use of its components, beyond the reckless generation of construction, materials that are often discarded as ?rubble?, affects directly affect the environment, the society and cities. Construction waste is already used in many European countries as recycled aggregates for concrete mix with for structural purposes. In Brazil, its use is still restricted to concrete without structural function, because the characteristics of the recycled aggregates can increase the permeability of the concrete. Due to the high porosity of the recycled aggregate when compared to the natural ones, it is expected that the concrete produced with the recycled aggregate higher porosity and consequently, fluids and gases will be easier to penetrate inside, directly affecting the durability and the useful life of reinforced concrete structures. In order for recycled aggregates to be a possible substitute for natural aggregates in the concrete mix for structural purposes, this work aims to study the parameters that affect the durability, determining and comparing through laboratory tests the physical and mechanical characteristics of concrete produced with different types of recycled aggregate. Four different types of coarse aggregates were defined for the accomplishment of this work, natural (AN), concrete (ARCO), cement-based materials aggregate (ARCI) and treated cement-based materials aggregate and two levels of natural aggregate replacement by aggregates recycled, 20 and 30% were employed. The concretes were tested in the ages of 7, 28, 90, 180 days and after 180 days of immersion in saline solution. The physical and mechanical characteristics of the concretes were determined, as well as indirect measurements of durability, such determination of air permeability, chloride ion penetration, carbonation and migration of chloride ions. The results indicated that concrete using recycled concrete aggregate (ARCO) produced 100% of crushed concrete presented characteristics similar to conventional concrete, and that the increase in the substitution content of 20 to 30% did not cause significant loss in concrete characteristics. As for the cement-based materials aggregate (ARCI), the results obtained for concrete with 30% substitution content were higher than for the concrete produced with the substitution content of 20%, and when compared to the conventional concrete the results presented by both concretes were inferior. However, for the substitution content of 30% even the results being inferior to the conventional concrete it presented good mechanical behavior. The concretes produced with the treated cement-based materials aggregate (ARCI Treated) did not present better performance than those with cement-based materials aggregate (ARCI) for most of the characteristics evaluated indicating that the proposed treatment was not adequate. / A constru??o civil ? uma das ind?strias que mais causam impacto ao meio ambiente. A extra??o desenfreada dos recursos naturais, a produ??o de cimento, a produ??o de concreto e a utiliza??o dos seus componentes, al?m da gera??o imprudente dos res?duos de constru??o civil, materiais esses que muitas vezes s?o descartados como ?entulho? afeta diretamente o meio ambiente, ? sociedade e ?s cidades. Os res?duos de constru??o civil j? s?o utilizados em muitos pa?ses da Europa como agregados reciclados para a mistura de concreto com fins estruturais. No Brasil, a sua utiliza??o ainda ? restrita a concretos sem fun??o estrutural, devido ? grande variabilidade do agregado reciclado, e o que elas influenciam nas caracter?sticas do concreto e em sua durabilidade. Devido ? alta porosidade do agregado reciclado quando comparado ao agregado natural, espera-se que o concreto produzido com o agregado reciclado apresente maior porosidade. E, consequentemente, flu?dos e gases possuam maior facilidade em penetrar em seu interior, afetando diretamente a durabilidade e a vida ?til das estruturas de concreto armado. Para que seja poss?vel a amplia??o no campo de consumo dos agregados reciclados, este trabalho tem como objetivo estudar os par?metros que afetam a durabilidade, determinando e comparando atrav?s de ensaios laboratoriais as caracter?sticas f?sicas e mec?nicas de concretos produzidos com diferentes tipos de agregado reciclado. Foram definidos quatro diferentes tipos de agregados gra?dos para a realiza??o deste trabalho, o natural (AN), o de concreto (ARCO), o ciment?cio (ARCI) e o ciment?cio tratado (ARCI Tratado) e dois teores de substitui??o do agregado natural pelos agregados reciclado: 20 e 30%. Os tra?os de concreto foram ensaiados para as idades de 7, 28, 90, 180 dias e ap?s 180 dias de imers?o em solu??o salina. Foram determinadas as caracter?sticas f?sicas e mec?nicas dos concretos, al?m de ensaios de medi??o indireta da durabilidade, como a determina??o da permeabilidade ao ar, penetra??o de ?ons cloreto, carbonata??o e migra??o de ?ons cloreto. Os resultados obtidos demonstram que concreto utilizando o agregado reciclado de concreto (ARCO) produzido com 100% de concreto britado apresentou caracter?sticas similares ao concreto convencional, e que o aumento no teor de substitui??o de 20 para 30% n?o ocasionou perda significativa nas caracter?sticas do concreto. Quanto ao agregado ciment?cio (ARCI), os resultados obtidos para o tra?o com teor de substitui??o de 30% foram superiores daqueles com o tra?o produzido com o teor de substitui??o de 20%, e quando comparados ao concreto convencional os resultados apresentados para ambos os tra?os foram inferiores. Por?m, para o teor de substitui??o de 30% mesmo os resultados sendo inferiores ao concreto convencional foi obtido um bom comportamento mec?nico. Os concretos produzidos de agregado ciment?cio tratado (ARCI Tratado) n?o apresentaram melhor desempenho que os com agregado ciment?cio (ARCI) para a maioria das caracter?sticas avaliadas indicando que o tratamento proposto n?o foi adequado.
26

A influência do uso da argamassa estabilizada na diminuição de impactos ambientais

Weissheimer, Luís Fernando 24 March 2017 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-06-12T16:55:47Z No. of bitstreams: 1 Luís Fernando Weissheimer_.pdf: 3421242 bytes, checksum: 04b1fa9c628dd1d13a12334fe2e6e93b (MD5) / Made available in DSpace on 2017-06-12T16:55:47Z (GMT). No. of bitstreams: 1 Luís Fernando Weissheimer_.pdf: 3421242 bytes, checksum: 04b1fa9c628dd1d13a12334fe2e6e93b (MD5) Previous issue date: 2017-03-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / A construção civil é uma atividade fundamental para o desenvolvimento da sociedade, gerando empregos, qualidade de vida e desenvolvimento econômico. Porém, através do uso descontrolado de recursos naturais, tem gerado grande volume de resíduos e impactos ambientais negativos consideráveis. Ao passo que novas tecnologias surgem como alternativas ao tradicional desperdício presente nessa atividade, esse estudo analisou a influência da substituição do uso de argamassa convencional pelo uso de argamassa estabilizada na geração dos resíduos classificados como Classe A pela Resolução 307 (CONAMA, 2002). Para tal, foram quantificados os resíduos gerados durante a execução de três obras residenciais verticais, denominadas Edifícios A, B e C, avaliando-se, por meio de técnicas estatísticas, a variação na taxa de geração de resíduo Classe A em decorrência da mudança do sistema de produção de argamassa convencional (A e B) para o sistema de argamassa estabilizada (C). Após a análise dos resultados, considerando que o único sistema construtivo que sofreu alteração foi o tipo de argamassa, constatou-se redução na taxa de geração de RCD Classe A de aproximadamente 31% no edifício C, onde foi utilizada a argamassa estabilizada, em comparação com a média dos Edifícios A e B, onde foi utilizada argamassa convencional. Foram, ainda, coletadas amostras de cada tipo de argamassa, enviadas para análises de lixiviação e solubilização frente aos critérios da NBR 10.004 (ABNT, 2004), não sendo apontadas diferenças significativas entre as amostras para esses parâmetros, concluindo-se que utilização da argamassa estabilizada reduz de forma significativa a quantidade de RCD no canteiro de obras, sem o aumento de risco de contaminação ambiental por parte do mesmo. / Civil construction is a fundamental activity for society’s development, generating jobs, life quality and economic development. However, through the uncontrolled use of natural resources, it has generated a large amount of waste and considerable negative environmental impacts. While new technologies arise as alternatives to the traditional waste present in this activity, this study analyzed the influence of the replacement of conventional mortar by the use of stabilized mortar in the generation of waste classified as Class A by Resolution 307 (CONAMA, 2002). For this, the waste generated during the execution of three vertical residential buildings, named Buildings A, B and C, were quantified, using statistical techniques to evaluate the variation in the rate of generation of Class A waste due to the change in the system of conventional mortar (A and B) for the stabilized mortar system (C). After the results analysis, considering that the only construction system that changed was the type of mortar, it was verified a reduction in the rate of generation of Class A CDW of approximately 31% in Building C, where the stabilized mortar was used, in comparison with the average of Buildings A and B, where conventional mortar was used. Samples were also collected from each type of mortar, sent for leaching and solubilization analyzes against the criteria of NBR 10.004 (ABNT, 2004). Since no significant differences between the samples were indicated for these parameters, it was concluded that the use of mortar reduces significantly the amount of CDW at the construction site, without increasing the risk of environmental contamination by the same.
27

Resíduos da construção civil no município de Palmas - Tocantins: proposição de um modelo de boas práticas de manejo

Barreto, Onésima Aguiar Campos 25 July 2016 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-12-22T14:40:54Z No. of bitstreams: 1 Onésima Aguiar Campos Barreto_.pdf: 819320 bytes, checksum: 77032227ee24042f8cd627cc2eef5be9 (MD5) / Made available in DSpace on 2016-12-22T14:40:54Z (GMT). No. of bitstreams: 1 Onésima Aguiar Campos Barreto_.pdf: 819320 bytes, checksum: 77032227ee24042f8cd627cc2eef5be9 (MD5) Previous issue date: 2016-07-25 / Nenhuma / A indústria da construção civil exerce uma grande contribuição para o desenvolvimento da economia dos países, principalmente se considerada a quantidade de empregos gerados e a influência direta em todos os setores que produzem insumos, equipamentos e serviços para a utilização no seu processo produtivo. Apesar desse grande destaque da indústria da construção civil brasileira na economia nacional, o setor é grande consumidor de recursos naturais, pois as obras utilizam grande quantidade e variedade de materiais de construção que, na maioria das vezes, por falta de planejamento, são desperdiçados e transformados em Resíduos da Construção Civil (RCC). O crescimento progressivo dos RCC tem ocorrido juntamente com o aumento da população, e traz consigo problemas ambientais em virtude do crescimento da construção civil, que no intuito de atender as expectativas da sociedade, caminham lado a lado com este crescimento. O município de Palmas/TO nos últimos anos vem passando por um processo acelerado de verticalização, acompanhado da geração de uma grande quantidade de RCC. No que tange às disposições desses resíduos no município e os impactos que eles provocam, esta pesquisa propôs diagnosticar a atual situação, baseado em um framework teórico de boas práticas e manejo, e da classificação e quantificação dos RCC gerados pelo período de um ano. Estas informações subsidiaram a elaboração de um manual de gerenciamento baseado em boas práticas de gestão e manejo. O método de pesquisa caracteriza-se como abordagem qualitativa, de natureza aplicada, com objetivos, exploratório e descritivo, sendo utilizados como método de trabalho, a pesquisa bibliográfica, documental e estudo de caso. Os dados foram coletados através da aplicação de questionários abertos e entrevistas com roteiro previamente definido. Os principais achados são: a falta de fiscalização e ineficiência da administração pública municipal; e a falta de gerenciamento ambientalmente correto pelas empresas construtoras, que as impedem de terem ganhos financeiros com a reutilização e reciclagem dos RCC. As recomendações para trabalhos futuros tratam-se da investigação da eficácia das certificações ISO 9001 e P-BQPH nas empresas construtoras, em especial no município de Palmas; a viabilidade do ponto de vista técnico e ambiental da adoção do manual de boas práticas proposto, para que se comprove sua eficácia quanto ao gerenciamento dos RCC, e por fim, a aplicação do framework teórico em estudos de campo. / The construction industry has a significant contribution to the countries’ economy development, especially if considered the created jobs amount and the direct influence across the sectors that produce raw materials, equipment and services for use in its production process. In spite of this major highlight of Brazilian civil construction industry in the national economy, the sector is large consumer of natural resources, since the construction uses building materials in large quantity and variety , most often, for lack of planning, are wasted and turned into Construction Waste (CW) The progressive growth of the CW has been in conjunction with an increase in population, and bring with them environmental problems arising from construction growth that in order to attend the expectations of society go hand in hand with this development. the city of Palmas/TO in the past years has experienced an accelerated process of verticalization, accompanied by the generation of a large amount of CW. Regarding to the provisions of this waste in the city and the impacts they cause, this research proposed to diagnose the current situation, based on a theoretical framework of good practices and managing, and classification and quantification of CW generated for a period of one year. This information supported the development of a management guide based on best management and handling practices. The research method is characterized as a qualitative approach, with applied nature, exploratory and descriptive objectives, being used as a working method, bibliographical, documentary research and case study. Data were collected through the application of open questionnaires and interviews with pre-defined script. The main findings are: the lack of supervision and inefficiency of the municipal government; and the lack of environmentally proper management for construction companies, preventing them from having the financial gains from the reuse and recycling of CW. Recommendations for future studies are: the investigation of the effectiveness of ISO 9001 and PBQP-H certifications in construction companies, especially in the city of Palmas; the viability of the technical and environmental point of view of the adoption of the proposed the best management guide, in order to prove its effectiveness as the management of CW, and finally, the application of theoretical framework on field studies.
28

Desempenho de argamassas de revestimentos produzidas com agregados reciclados oriundos do res?duo de constru??o e demoli??o da Grande Natal-RN / Performance of mortar coating produced with recycled aggregates derived from construction and demolition waste (CDW) produced in the Grande Natal-RN

Ara?jo, Neuber Nascimento de 28 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:48:17Z (GMT). No. of bitstreams: 1 NeuberNA_DISSERT.pdf: 3614551 bytes, checksum: 214bf692c54f433fec3b97fdac3c0659 (MD5) Previous issue date: 2014-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The construction industry is responsible for generating a lot of waste because of their activities. Consequently, it is noticeable the occurrence of environmental problems in terms of its disposal in inappropriate places. Faced with this problem, some studies have been conducted with the aim of developing technologies and alternatives for recycling construction and demolition waste (CDW), motivated by the scarcity of natural resources and reduction of environmental problems generated. The research aims to characterize the recycled aggregates derived from construction and demolition waste (CDW) produced in the Greater Natal-RN and analyze the performance of mortar coating produced with recycled aggregates. The study includes the chemical , physical and microstructural characterization of recycled aggregates , as well as conducting microscopic analysis and laboratory tests in the fresh state (consistency index , water retention , bulk density and content of entrained air ) and in the hardened state ( compressive strength , tensile strength in bending , water absorption by immersion and capillary , mass density and void ratio ) for mortars produced from different levels of substitution of aggregates ( 0, 20 %, 40 %, 60 %, 80 % and 100 %). The results were satisfactory, providing mortars produced with recycled aggregates, smaller mass density and dynamic modulus values as well as an increase in the rates of absorption and porosity. The tensile strength in bending and compression for TP1 (1:2:8) trait were lower for mortars produced with recycled aggregates and the best result was 20% for replacement. For the TP2 (1:8) mapping, there was an increase in resistance to traction and compression and the best result was for 100% replacement of natural aggregates by recycled. The experiments led to the conclusion that the technical and economic point of view that the mortars produced with recycled aggregates can be used in construction, only if there is an effective control in production processes of recycled aggregate and at the dosage of mortars / A ind?stria da constru??o civil ? respons?vel por gerar uma grande quantidade de res?duos em fun??o de suas atividades, ocasionando problemas ambientais, econ?micos e sociais. Diante dessa problem?tica, alguns estudos v?m sendo realizados com o objetivo de desenvolver tecnologias e alternativas de reciclagem para os res?duos de constru??o e demoli??o (RCD), motivados pela escassez de recursos naturais e pela diminui??o dos problemas ambientais gerados. A pesquisa tem por objetivo caracterizar os agregados reciclados produzidos na Grande Natal-RN e analisar o desempenho de argamassas de revestimento produzidas com estes agregados. O estudo inclui a caracteriza??o qu?mica, f?sica e microestrutural dos agregados reciclados, assim como a realiza??o de an?lises microsc?picas e ensaios laboratoriais das argamassas no estado fresco (?ndice de consist?ncia, reten??o de ?gua, densidade de massa e teor de ar incorporado) e no estado endurecido (resist?ncia a compress?o, resist?ncia a tra??o na flex?o, absor??o de ?gua por imers?o e por capilaridade, densidade de massa e ?ndice de vazios), para argamassas produzidas a partir de diferentes teores de substitui??o de agregados (0, 20%, 40%, 60%, 80% e 100%). Os resultados obtidos foram satisfat?rios, proporcionando ?s argamassas produzidas com agregados reciclados, valores menores de densidade de massa e m?dulo de elasticidade din?mico, assim como um incremento nos ?ndices de absor??o e porosidade. A resist?ncia ? tra??o na flex?o e ? compress?o para o tra?o TP1 (1:2:8) foram inferiores para as argamassas produzidas com agregados reciclados e o melhor resultado foi para 20% de substitui??o. Para o tra?o TP2 (1:8), ocorreu um incremento na resist?ncia ? tra??o e ? compress?o e o melhor resultado foi para 100% de substitui??o dos agregados naturais pelos reciclados. Os experimentos conduziram a concluir que do ponto de vista t?cnico, as argamassas produzidas com agregados reciclados podem ser utilizadas na constru??o civil, desde que haja um controle eficiente nos processos de produ??o do agregado reciclado e na dosagem das argamassas
29

Development of wood-crete building material

Aigbomian, Eboziegbe Patrick January 2013 (has links)
Main concerns in the building industry includes the development of alternative building materials that reduces the amount of energy spent during manufacturing process and easier to work with. Wood-crete is a composite material developed in this study, made up of wood waste (sawdust), paper, tradical lime and water. Wood-crete is developed to provide an alternative material in construction solving problems associated with the delivery of low-cost housing across all income earners, reducing the amount of energy spent during manufacturing process of construction materials and the ease with which these construction materials are developed and solve issues related to waste management. This thesis presents the processing technologies, factors which affect the performance and properties of wood-crete. Wood-crete properties were found to be closely related to the composition of the constituent elements though compressive strength and modulus of elasticity were low when compared to other building materials like concrete and steel. In a bid to improve the strength of the developed wood-crete, the properties were investigated based on the modification of sawdust by hot water boiling and alkaline treatments which help to modify cellulose fibre surface to reduce the hydrophilic nature of sawdust thereby improving the sawdust-matrix bonding. It was found that the surface modification, processing of cellulosic fibril and the extraction of lignin and hemi-cellulosic compounds with alkali had an effect on the compressive strength of wood-crete, with treating sawdust with 4% NaOH at 140mins of boiling time achieving the highest compressive strength and boiling sawdust from 100mins to 140mins had a gradual increase in compressive strength but reduced at higher boiling time. Furthermore, treating sawdust with NaOH more than 4% weakened the individual wood particles thus leading to poor strength of wood-crete. Additionally, the properties of wood-crete were investigated based on the type of wood sawdust – hardwood (beech and oak) and softwood (pine and cedar). Apart from individual wood density having a significant effect on the density of wood-crete, other factors such as lignin, cellulose, hemicellulose contents including fibre length of individual wood species affect the strength properties of wood-crete. The compressive strength of wood-crete was closely related to the wood species, with highest compressive strength of 3.93MPa recorded for hardwood wood-crete compared to 1.37MPa and 0.26MPa of wood-crete from softwood and mixed wood respectively. Results from thermal conductivity tests on wood-crete also show that wood-crete blocks can be produced with good insulating properties for building construction. Addition of different types of paper fibres to reduce the density of wood-crete and improve the insulating properties of composite developed also had a dominant influence on both strength and thermal conductivity, reflecting its effect on the structure of composite and contribution of self strength of paper fibres. The addition of various percentages of waste paper (de-fibred) had a significant influence on the thermal conductivity of wood-crete with 75% addition of waste paper achieving a thermal conductivity value of 0.046W/mK performed with the TCi thermal conductivity analyser. Thermal conductivity results for wood-crete made from hardwood and softwood sawdust was closely related to the chemical composition of various wood species, with softwood wood-crete having about 20% lower thermal conductivity compared to hardwood wood-crete. The developed wood-crete was able to withstand impact load and considered, like hempcrete, most suitable for wall panelling or other non- and semi-structural applications with good thermal insulating properties. Findings of this study provides an alternative new material for the construction industry and an important background for achieving better strength of wood-crete, choosing what type of sawdust to be used for development of wood-crete and for directing a better use of this potential material with very small embodied energy and carbon negative.
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Avaliação da geração de resíduos da construção civil e suas implicações em bairros populares. O caso do bairro de Gramame em João Pessoa- PB.

Guedes, Ana Luisa Pires Gouveia 09 June 2014 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-01-04T15:08:21Z No. of bitstreams: 2 arquivototal.pdf: 5665029 bytes, checksum: 06bf4bbd17e5fc54dbfb8c73bb40b227 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-01-04T15:08:21Z (GMT). No. of bitstreams: 2 arquivototal.pdf: 5665029 bytes, checksum: 06bf4bbd17e5fc54dbfb8c73bb40b227 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-06-09 / The managers of cities have found it difficult to effectively manage the generation of civil construction waste (CCW) in order to solve the problem of irregular arrangements that compromise the quality of life of the population and cause serious environmental and health problems. For these reasons and due to housing growth driven by incentives from the Federal Government through the social program called Minha Casa Minha Vida (MCMV), the object of this study was to assess the generation of waste arising from civil construction of the popular buildings at two sites located in the neighborhood known as Gramame in the city of João Pessoa – PB, based on resolutions of the National Environment Council – CONAMA No. 307/2002 and No. 431/2011, and the National Policy of Solid Waste – PNRS (Law No. 12,305 of 2010). A qualitative and quantitative methodology was applied and had the following steps: Bibliographical Survey (survey, review and critical analysis of national and international literature); Documentary Research (visits to public administration, to companies that have implemented the land subdivisons Parque Sul II and Novo Milênio, and to companies that process the CCW); Field research (Interviews with questionnaires, Recognition of areas of study, Mapping and Quantification of CCW), Selection and Organization of Data and Analysis and Interpretation of Data. According to Law No. 11.176/07 from the city of João Pessoa, the CCW generated at the construction site should be segregated during execution of works. However, it was found that the waste is not subject to any kind of segregation. Based on the mapping done for three months in the land subdivisions, an average of fourteen points of irregular arrangement of CCW was found. According to the quantification in the foundation phase, the most discarded residue is sand (69%), and in the phase of structures, the most generated residue is the mortar (58%). Since the masonry, ceramic brick (42%) is the most discarded finishing step and the residue which is most generated is plaster (25%). Thus, this study aims to contribute to ensuring greater awareness of the problem presented by the generators and that a more efficient inspection by the appropriate agencies occurs. We propose measures to reduce waste, to reuse the CCW generated and to recycle the material at the building site. It also shows how design can influence the minimization of CCW. / Os gestores das cidades têm encontrado dificuldades tanto para gerenciar de forma eficaz a geração dos resíduos da construção civil (RCCs), quanto para solucionar o problema das disposições irregulares que comprometem a qualidade de vida da população e acarretam sérios problemas socioambientais e sanitários. Pelo exposto e devido ao crescimento habitacional impulsionado pelos incentivos do Governo Federal, através do programa Minha Casa Minha Vida (MCMV), o objeto do estudo deste trabalho foi avaliar a geração dos resíduos de construção civil oriundos das construções populares em dois loteamentos localizados no bairro Gramame no município de João Pessoa-PB, baseados nas Resoluções do Conselho Nacional de Meio Ambiente - CONAMA Nº 307/2002 e Nº431/2011, e na Política Nacional de Resíduos Sólidos - PNRS (Lei Nº 12.305 de 2010). A metodologia do trabalho foi de caráter qualitativo e quantitativo e teve as seguintes etapas: Pesquisa Bibliográfica (levantamento, revisão e análise crítica da literatura nacional e internacional); Pesquisa Documental (visitas a administração pública, a empresas que implementaram os loteamentos Parque Sul II e Novo Milênio e empresas beneficiadoras de RCCs); Pesquisa de Campo (Entrevistas com aplicação de questionários, Reconhecimento das áreas de estudo, Mapeamento e Quantificação dos RCCs), Seleção e Organização dos Dados e Análise e Interpretação dos Dados. De acordo com a Lei Nº 11.176/07 do município de João Pessoa, os RCCs gerados no canteiro devem ser segregados durante a execução das obras. Entretanto, foi verificado que os resíduos não são submetidos a nenhum tipo de segregação. Baseado no mapeamento realizado, durante 03 meses, nos loteamentos foi encontrado uma média de 14 pontos de disposição irregular de RCCs. Conforme a quantificação dos resíduos na etapa de fundação o resíduo mais descartado é a areia (69%), na etapa de estruturas o resíduo mais gerado é a argamassa (58%). Já na alvenaria, o tijolo cerâmico (42%) é o mais descartado e na etapa acabamento o resíduo mais gerado é gesso (25%). Dessa forma, o presente trabalho pretende contribuir para que haja uma conscientização maior sobre o problema apresentado por partes dos geradores e que ocorra uma fiscalização mais eficiente por parte dos órgãos competentes. Propõem-se medidas para redução do desperdício, para reutilização dos RCCs gerado e para a reciclagem na própria obra e mostra como o projeto pode influenciar na minimização dos RCCs.

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