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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

Resíduos da construção e demolição (rc&d): estudo dos impactos ambientais provocados pelo descarte inadequado no município de Presidente Bernardes – SP / Waste of Construction and Demolition (Rc&D): Study of the Environmental Impacts Caused by Disadvantaged in the Municipality of Presidente Bernardes - Sp

QUAGLIO, Renam Serraglio 24 November 2017 (has links)
Submitted by Adriana Martinez (amartinez@unoeste.br) on 2018-03-01T19:35:13Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) RENAM SERRAGLIO QUAGLIO.pdf: 4813087 bytes, checksum: d84dbcaf6484445e15d3364a5daf62a5 (MD5) / Made available in DSpace on 2018-03-01T19:35:13Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) RENAM SERRAGLIO QUAGLIO.pdf: 4813087 bytes, checksum: d84dbcaf6484445e15d3364a5daf62a5 (MD5) Previous issue date: 2017-11-24 / The urban centers produce a large amount of solid waste daily, among them we can highlight the construction and demolition waste (RCD) from the processes of construction, demolition and maintenance of civil works. Civil construction can be identified as one of the sectors that most cause impacts to the environment due to exploitation of natural resources and high rate of waste generation. The creation of irregular provisions in the urban perimeter is observed in public roads and public places, squares, slopes, water courses and areas of permanent preservation. In this context, this study aims to report on the possible environmental impacts caused in the areas of RCD irregularity in the municipality of Presidente Bernardes-SP, presenting its characteristics and spatial analysis. The methodological basis for the characterization of the areas was descriptive statistics. The quantitative and qualitative analyzes evaluated the generation rate and composition of RCDs in the municipality. After a detailed investigation of the urban perimeter and accesses of the municipality were demarcated 40 points of irregular disposal that had more than 3 m³ of deposited RCDs. These points were classified in public, private and permanent preservation areas. Class A, 82.5% of Class B, 47.5% of Class C and D (CONAMA 307/02) were identified in all the analyzed points, it was also verified that 20% of the points had household residues evidencing the power attractiveness of RCDs. The mortar was the most representative material with 22.58% of the analyzed sample, followed by concrete with 19.65%. The identified impacts were to the degradation of the disposal areas evidenced by the RCD composition, sedimentation and compromise of the Guarucaia stream, soil erosion, among others. The evaluation of municipal management pointed to the diagnosis of the system and environmental education as bad and the inspection as bad, based on the parameters analyzed. Such evaluations are fundamental for the identification of the fragilities of the management, and proposition of a management based on the principles of the sustainability. / Os centros urbanos produzem uma grande quantidade de resíduos sólidos diariamente, dentre eles podemos destacar os resíduos da construção e demolição (RCD) oriundos dos processos de edificação, demolição e manutenção de obras civis. A construção civil pode ser identificada como um dos setores que mais causam impactos ao meio ambiente devido à exploração dos recursos naturais e elevado índice de geração de resíduos. A criação de disposições irregulares no perímetro urbano é observada em vias e logradouros públicos, praças, encostas, cursos d’água e áreas de preservação permanente. Neste contexto, este estudo tem por objetivo relatar os possíveis impactos ambientais ocasionados nas áreas de disposição irregular dos RCD no município de Presidente Bernardes-SP apresentando suas características e análise espacial. A base metodológica para a caracterização das áreas foi à estatística descritiva. As análises quantitativas e qualitativas avaliaram a taxa de geração e a composição dos RCD no município. Após uma investigação detalhada do perímetro urbano e acessos do município foram demarcados 40 pontos de descarte irregular que possuíam mais de 3 m³ de RCD depositados. Estes pontos foram classificados em áreas públicas, particulares e em áreas de preservação permanente. Em todos os pontos analisados foram identificados resíduos da Classe A, 82,5% da Classe B, 47,5% da Classe C e D (CONAMA 307/02), também foi verificado que 20% dos pontos apresentavam resíduos domiciliares evidenciando o poder de atratividade dos RCD. A argamassa foi o material com maior representatividade com 22,58% da amostra analisada, seguida pelo concreto com 19,65%. Os impactos identificados foram à degradação das áreas de disposição evidenciadas pela composição dos RCD, assoreamento e comprometimento do córrego Guarucaia, erosão dos solos entre outros. A avaliação da gestão municipal apontou o diagnóstico do sistema e educação ambiental como péssimos e a fiscalização como ruim, a partir dos parâmetros analisados. Tais avaliações são fundamentais para a identificação das fragilidades do gerenciamento, e proposição de uma gestão baseada nos princípios da sustentabilidade.
62

Vliv umístění stavby na cenu a náklady stavebního objektu / The influence of the location of buildings on price and cost of a building

Petr, Lubomír January 2017 (has links)
The thesis deals with the influence of the location of buildings on the price and the cost of a building. In the first theoretical part it deals with brownfields, redevelopment of geological environment and construction and demolition waste. In this passage the various concepts, their division, the legislative side of things and generally their problems are explained. The second part is practical, it analyzes the cost associated with the revitalization of abandoned buildings for the possibility of reuse of land. For these purposes the representative brownfield is created and it is set in different environment. In conclusion all important findings are summarized.
63

Sustainability of Construction and Demolition Waste : A Closed-loop Supply Chain for Flat Glass

Dahl, Thor Lobekk, Lu, Yichang, Thill, Sidney Carina January 2021 (has links)
Purpose: This thesis’ purpose is to identify a CLSC model of flat glass, including actors,waste sources, and what can be done with recycled flat glass. In addition, this researchaims to propose a cost structure of a flat glass CLSC. Thus, this thesis’ research questions(RQ) are: RQ1: How can closed-loop supply chains (CLSC) for the purpose of flat glasslook like? RQ1.A: What actors are a part of a flat glass CLSC? RQ1.B: What are thewaste sources of flat glass in a flat glass CLSC? RQ1.C: What are the uses of flat glassas secondary material? RQ2: How can a cost structure for a closed-loop supply chain(CLSC) for the purpose of flat glass look like?  Method: For this purpose of this thesis the researchers chose to employ a pragmatistresearch philosophy. The thesis is an exploratory qualitative study using an abductiveapproach. A case study strategy was used, and data was collected through semi-structuredinterviews and a literature review. Seven interviews were conducted with the six casecompanies. Findings: A flat glass CLSC consists of three phases: manufacture, use, and secondary(raw) material. The main actors are float glass manufacturer, flat glass processor/refiner,flat glass distributor, construction and demolition company, flat glass recycler, and freighthauler. Sub-actors of a flat glass CLSC are raw materials supplier, government, thirdparty contractors, container glass manufacturer, and glass wool manufacturer. Secondarymaterial occurs during flat glass manufacturing, distribution/transport, construction, anddemolition. It can be divided into three types, i.e., pure, high quality cut-offs,contaminated flat glass, and end-of-use flat glass. The possible uses of flat glass assecondary material are float glass, container glass, and glass wool manufacturing. Thecost structure for a flat glass CLSC divides cost elements into the three phases of a flatglass CLSC and six supply chain cost categories, which include manufacturing cost,distribution cost, warehousing cost, administration cost, capital cost, and installation cost. Theoretical Implications: This master’s thesis helps in adding to two research areas: flatglass and CLSC. By reviewing existing literature and conducting the case studies inChina, Germany, and Norway, the researchers can reflect the current practices of flat glassCLSCs in different countries, thereby adding to existing scientific research to close theresearch gap of flat glass CLSCs. Practical Implications: This master’s thesis contributes to practice by providing a flatglass CLSC model and cost structure which can be used as a starting point of developinga flat glass CLSC and its cost structure. In addition, this thesis is connected to anotherbigger research project in collaboration with the Linnaeus University and the city ofVäxjö, the findings from this thesis are beneficial for improving the situation of flat glassin Sweden. Societal Implications: By researching circularity in CDW, this master’s thesis helps notonly the city of Växjö but also other Swedish cities to improve the situation of flat glassand strive towards a full circular economy, further contributing to an increase insustainability in Sweden.
64

Assessing Condition on Alkali-Silica Reaction (ASR) Affected Recycled Concrete

Zhu, Yufeng 06 October 2020 (has links)
Many highway and hydraulic structures in North America have been reported to be affected by alkali aggregate reaction (ASR). It is anticipated that most of these structures will be demolished as they approach the end of their service lives. Recycling demolished concrete as aggregates in new concrete is an option that not only reduces the amount of construction demolition waste (CDW) disposed in landfills but also lessens the consumption of non-renewable resources such as natural aggregates. However, the use of recycled concrete aggregate (RCA) in new concrete requires detailed research to make sure that the durability of the recycled material is not compromised, especially if the RCA had been previously affected by ASR. In this research project, coarse recycled concrete aggregate (RCA) is reclaimed and processed from distinct members (i.e. foundation blocks, bridge deck and columns) of an ASR-affected overpass after nearly 50 years of service. RCA concrete mixtures incorporating 50 and 100% replacement are manufactured and stored in conditions enabling further ASR development. Mechanical (i.e. Stiffness Damage Test - SDT) and microscopic (Damage Rating Index - DRI) analyses are performed at a fixed “secondary” induced expansion of 0.12%. Results show that the overall performance of the ASR-affected recycled mixtures depends upon the “past” condition of the RCA particles. Moreover, the DRI was able to capture the “past” and “secondary” induced expansion and damage of affected RCA while the SDT only detected the “secondary” distress development. Lastly, an adapted version of the DRI was proposed to further evaluate the overall damage of recycled concrete along with properly displaying “past” and “secondary” induced distress.
65

Construction and demolition waste in Helsinki : Case study of the circular economy hub HSY Ekomo / Bygg- och rivmatieral i Helsingfors : En case studie av cirkulär ekonomi stationen HSY Ekomo

Wikström, Erik January 2018 (has links)
The limited amount of natural resources on our planet has been actively discussed during the past decade. Recycling materials is becoming increasingly important in order to benefit the economy and the environment. The purpose of this study is to conduct a material flow analysis of the construction and demolition waste in the Helsinki metropolitan area to find out whether or not the goals set by the EU Waste Framework Directive can be reached by 2020. The study aims to map out the flows and suggest improvements wherever needed. The study is conducted by using a case study, HSY Ekomo, the first fully operational circular economy hub in Finland. The results show that both the municipality and private sector are well over the required goal of 70% recyclability rate of construction and demolition waste with a steady positive improvement from the first year of operations. The improvements were over 10% between the year 2016 and 2017. The private sector experiences some turbulence regarding legislation issues such as noise- and environmental permits which limits the economic benefit of recycling construction and demolition waste. Continued monitoring and faster adaption to international standards (such as the EU Waste Framework Directive) is required in order to be able to benefit the most economically and environmentally out of circular economic initiatives. / Den begränsade mängden naturresurser som existerar på vår planet har diskuterats under det senaste decenniet aktivt. Återvinning av material blir allt viktigare i dagens samhälle och vi kan se en trend var utvecklingen strävar efter beslut som har rötterna i cirkulär ekonomiskaprinciper. Resultatet av diskussionerna har blivit höga måtsättningar för medlemsländerna i Europeiska Unionen gällande återvinning var målet är att uppnå en återvinningsgrad på 70% innan 2020 för bygg- och rivavfall. Studien använder materialflödes analys (MFA) som metod för att kartlägga och kvantifiera flödnena av bygg- och rivavfall. Materialflödes analysen använder data från årsrapporter och statistik som blivit tillgängligt av HSY (statligt ägt bolag) samt av intervjuerna som utfördes på fältet. För att kvantifiera flödena på basis av den konceptuella modellen avnändes mjukvaran STAN. Avhandlingen strävar efter att ta första steget för att kartlägga materialflöden av bygg- och rivavfall i huvudstadsregionen (Helsingfors). Målet är att skapa en modell som kan användas som botten i framtida undersökningar och att kvantifiera modellen med existerande data för att se ifall målsättningarna stadgade av Europeiska Unionen kommer att uppnås innan 2020. Studien utfördes på cirkulär ekonomi stationen Ekomo för att kunna göra upp modeller för den privata sektorn och den kommunalla sektorn eftersom båda är verksamma på Ekomo. Resultaten av anvhandlingen var följande: Den privata sektorn och staten uppnår en återvinningsgrad på över 90% vilket är väl över stadgan satt av den Europeiska Unionen under året 2017 med en stadig utveckling från året innan med en väldigt liten andel som placeras på soptipp. Resultaten visar en stark utveckling av intresse från hushåll och företag för återvinning eftersom antalet kunder och lastbilar som besökt stationen ökat starkt under de senaste fem åren. Även om målsättningarna inom återvinning är uppnådda finns det ärenden som måste behandlas för att försäkra en fortsatt positiv utveckling. Den privata sektorn upplever att begränsade möjligheter för återanvänd krossbetong minskar efterfrågan på produkten, vilket gör den finansiellt svår att integrera i deras försälning. Buller- och miljötillstånd tvingar för tillfället bolagen att transportera bygg- och rivmaterialet utanför rivmålet, t.ex till Ekomo, för att krossas vilket ytterligare skapar finansiella problem för den privata sektorn. Lösningar för att göra återvinning av riv- och byggnadsmaterial för den privata sektorn lukrativare behövs för att inspirera flera organisationer att ansluta sig till arbete mot ett mera cirkulärt samhälle. Monitorering och snabbare anpassningsförmåga för internationella standarder krävs för att kunna utnyttja cirkulär ekonomiska initiativ på bästa möjliga sättet. För att komplettera avhandlingen skulle det vara intressant att se resultaten av en livcykelanalys (LCA) gällande samma flöden för att identifiera miljörelaterade problem och för att optimera flöden.
66

Avfall i byggbranschen : En fallstudie av ett projekts arbete med avfallshantering

Gustafson Nilsson, Elin January 2023 (has links)
The construction sector today accounts for a big part of the totalamount of waste in Sweden and we need to save the earth’srecourses. To save our resources when processing waste it is best tofollow the waste ladder. It’s very important for all of our sake thatwe handle the waste properly. In the summer of 2020 new lawswere applied to ensure that construction waste is being handled ina proper way. For this study the waste disposal management of aspecific company was studied to see how their current work withwaste disposal and what improvements can be made. By usingliterature study, qualitative interviews, quantitative survey, ocularinspection and document analysis a result has been formed. Theresult that can be seen in this study is that the company in questionis following the requirements for waste disposals but there areroom for improvements. The conclusion from this study is that theleadership and employees in the company is in need of betterknowledge on how to properly manage the waste from theconstruction sites. / Byggsektorn står idag för en stor del av Sveriges totalaavfallsmängd och vi behöver spara på jordens resurser. För attspara på resurserna är det viktigt att bearbeta avfallet på bästa sättutifrån avfallstrappan. Det är viktigt att avfall hanteras på rätt sättbåde för miljön och människors skull. För att bygg- ochrivningsavfall ska hanteras på bästa sätt trädde sommaren 2020nya lagar kring avfallshantering i kraft. I studien har ett företagsarbete med avfallshantering studerats med syfte att se hur manarbetar med avfallshantering samt att hitta förbättringsmöjligheterför företaget. Genom litteraturstudie, kvalitativa intervjuer,kvantitativ enkät, okulär besiktning och dokumentanalys harstudiens resultat tagits fram. Resultatet som framkommer är attföretaget följer de krav som ställs på dem men att det finnsförbättringsmöjligheter. Slutsatsen är att företaget behöver arbetamer med att utbilda både arbetsledningen och yrkesarbetarna ivilka lagar och krav som ställs på avfallshanteringen vidbyggprojekt. / <p>2023-06-26</p>
67

Beställarens roll för ökat återbruk av byggmaterial : En kvalitativ intervjustudie / The client's role for increased reuse of building materials : A qualitative interview study

Waern, Max January 2021 (has links)
Sveriges byggbransch genererar årligen stora mängder avfall som under 2018 uppgick till 13 miljoner ton vilket motsvarar 35 % av Sveriges totala genererade avfall. För att klara de globala hållbarhetsmålen och minska byggbranschens klimatpåverkan behöver resursanvändningen och uttaget av jungfruliga resurser minska. Diskussionen om ett hållbart samhällsbyggande kretsar kring en fossilfri och resurseffektiv värdekedja och kräver en övergång till cirkulära flöden. I byggbranschen är beställaren den huvudsaklige kravställande parten som besitter stor potential till förändring av hela branschen men den egna medvetenheten hos beställare varierar kraftigt beroende på målgrupp, organisationens storlek och ekonomiska förutsättningar. I denna studie har en intervjustudie genomförts för att undersöka beställarens roll för ökat återbruk av byggmaterial vilket lett till insikter om beställarens roll samt de främsta utmaningar för nämnt syfte. Respondenterna i studien har varit yrkesverksamma i byggbranschen med olika grad av professionell erfarenhet av återbruk av byggmaterial, som representerat olika typer av aktörer inom byggbranschen. I forskningen studeras idag möjligheten till återbruk av byggmaterial i innovations- och pilotprojekt för att hitta arbetsmetoder och lösningar för större flöden av återbrukat material och produkter inom byggbranschen. Denna studie har som avsikt haft att fortsatt undersöka återbrukets potential och utmaningar utifrån ett beställarperspektiv på en branschnivå och har resulterat i kunskap om beställarens roll för ökat återbruk av byggmaterial. Studien visar att beställaren besitter en nyckelroll för att driva förändringsarbetet inom branschen. Det framgår att det finns stora skillnader i beställarens medvetenhet över branschen och att de största aktörerna driver framgångsrika projekt med fokuserat återbruksarbete. Samtidigt är mindre beställare, som till antalet utgör stor del av byggbranschens aktörer, långt ifrån att driva återbruk som en del av hållbarhetsfrågan på grund av okunskap och avsaknad av efterfrågan från kunder. Studien presenterar även de främsta utmaningar som branschens beställare står inför för att gå mot större flöden av återbrukat byggmaterial. Dessa utmaningar visar sig vara; kunskapsbrist och erfarenhet, bristen på aktörer som arbetar med återbruk, att nya arbets- och tankesätt måste realiseras, att det befintliga regelverket måste förändras till att gynna återbruk, att stora delar av branschen inte är redo, logistik och lagerhantering samt medvetenheten om ekonomiska förutsättningar. För att vidare studera återbruk inom byggbranschen vore det intressant att studera olika entreprenadformers påverkan på återbruksmöjligheter. En annan intressant tråd att arbeta med vore att ta fram konkreta ekonomiska incitament för minskat avfall och ökat återbruk från höga strategiska nivåer för att på en branschnivå driva förändringsarbetet mot cirkulära flöden. Som vidare undersökning utifrån denna studie vore det av stort värde att genomföra en större kvalitativ studie med statistiska slutsatser som kan bidra med underlag för beslut för beställare och lagstiftning. / Sweden's construction sector generates large amounts of waste annually and amounted 2018 to 13 million tonnes of waste, which corresponds to 35 % of Sweden's overall generated waste. In order to meet the global sustainable development goals and reduce the climate impact of the construction sector, the use of resources and the abstraction of virgin resources need to be reduced. The discussion about sustainable construction development revolves around a fossil-free and resource-efficient value chain and requires a transition to circular material and economic flows. In the construction sector, the client is a demanding party who has great potential to push for change over the entire industry, but the self-awareness of the client varies greatly depending on the target group, the size of the organisation and economic conditions of the client’s organisation. In this study, an interview study has been conducted to investigate the client's role in increasing reuse of building materials, which has led to insights into the role of the client as well as the main challenges for the stated purpose. The respondents of the study are professionals in the construction industry with various levels of professional experience in the reuse of construction materials, representing different types of actors in the construction industry. Researchers are currently studying innovation and pilot projects to find new or improved working methods and solutions for greater volumes of recycled materials and products. This study aims to continue to investigate the potential and the arisen challenges of reuse from a client's perspective at an industry level and has resulted in knowledge of the client's role in increased reuse of building materials. The study shows that the client has a key role to play in driving change in the industry. Even though, it appears to be major differences in the client’s awareness across the industry and the largest actors are running successful projects with focused reuse work. At the same time, smaller client’s, who make up a large part in number of the industry's actors, have long ways to go before adopting reuse as part of the sustainability issue due to inexperience and lack of demand from customers. The study also presents the identification of the main challenges for the industry's clients in order to move towards industrial volumes of reused building materials. These challenges are: lack of knowledge and experience, the lack of actors working with reuse, the realisation of new ways of working and thinking, the need to change the existing regulatory framework to promote reuse, a large number of actors are not ready to adopt methods of reuse, logistics and warehousing, and awareness of economic prerequisites.  In order to further study reuse in the construction industry, it would be interesting to study the impact of different project delivery methods and its impact on reuse opportunities. Another interesting thread to follow up on would be to develop tangible financial incentives, for reduced waste and increased volumes of reused materials, from high strategic levels in order to drive change towards a circular economy. As a continuation of this study, it would be of great value to conduct a larger quantitative study with statistical deductions that can provide a basis for decisions for clients and legislative advancement.
68

Mass Logistics Centres and Social Impacts : Investigating the Challenges and Solutions in Urban Residential Areas / Masslogistikcentra och sociala effekter : Undersöka utmaningarna och lösningarna i urbana bostadsområden

Brandt, Barbara Iwona January 2024 (has links)
Addressing the amount of construction and demolition waste (CDW) is crucial for transitioning into a sustainable and circular economy, and therefore supports reaching climate neutrality in the European Union by the year 2050. One important solution for CDW recovery is placing mass logistic centres (MLCs) near construction projects. MLCs contribute to reducing environmental emissions, improving transport efficiency, and increasing economic benefits. However, when MLCs are built in proximity to residential areas they are often associated with a negative social impact. The present study aims to develop a strategy to improve planning processes and design for MLCs to have a positive impact on local communities. The research is done through case studies of existing MLCs near residential areas, using public surveys and focus group workshops. The data shows that the residents’ main concerns are environmental impacts and safety, noise and pollution levels, disturbances from heavy traffic, and disturbances to places' identity and facilities' aesthetics. The study concludes that the most important aspects of a more considerate MLC design are maintaining open and inclusive communication with the local community during early planning stages as well as during construction and operations, considering and responding to the residents’ concerns, as well as gaining an understanding of the place's identity. As this is a novel topic within the field, more extensive research is required to further investigate both challenges and solutions for local communities related to MLCs being located near their residential areas. / En viktig lösning för återvinning av bygg- och rivningsavfall (CDW) är masslogistikcentraler (MLC) nära byggprojekten. MLC bidrar till att minska miljöutsläpp, förbättra transporteffektiviteten och är även ekonomiskt fördelaktigt. Att ligga nära byggprojekt innebär dock ofta att de kommer ligga nära befintliga bostadsområden, särskilt i samband med förtätning. Denna studie syftar till att utveckla en strategi för förbättrade planeringsprocesser och design för MLC som tar större hänsyn till närboende och näraliggande verksamheter. Studien har utförts genom fallstudier av befintliga MLC nära bostadsområden med hjälp av enkäter och workshops med fokusgrupper för att samla in nödvändiga data. Resultaten visar att invånarnas huvudsakliga oro rör miljöpåverkan och säkerhet, buller- och föroreningsnivåer, störningar från tung trafik, påverkan på platsens identitet samt anläggningens estetiska utformning. Studien drar slutsatsen att de viktigaste aspekterna för att MLC ska utformas mer hänsynsfullt för lokalsamhället är förbättrad planering med tidigt samarbete med närboende; att beakta och svara på invånarnas oro och få en förståelse för platsens identitet; samt att upprätthålla en öppen och inkluderande kommunikation med lokalsamhället under byggandet och driften. Ämnet för studien är i sin linda och mer forskning krävs för att ytterligare undersöka både utmaningar och lösningar för de lokalsamhällen som påverkas av att anläggningarna ligger nära deras bostadsområden.
69

A formação da mineração urbana no Brasil: reciclagem de RCD e a produção de agregados. / The formation of urban mining in Brazil.

Lima, Francisco Mariano da Rocha de Souza 07 March 2013 (has links)
A nova Política Nacional de Resíduos Sólidos no Brasil, consubstanciada na lei 12305 /2010, possibilita o emprego de instrumentos econômicos para o fortalecimento de um mercado de agregados reciclados ainda nascente, no qual a maior parte dos resíduos de construção e demolição (RCD) ainda não é reciclada. Este trabalho tem fundamentos técnicos em duas áreas do conhecimento: a engenharia mineral e a construção civil. Na área mineral, será analisado o tratamento do RCD, processado como um minério. Na cadeia da construção civil, o foco é o uso dos agregados reciclados obtidos a partir dos resíduos da construção e demolição, que permite a valorização do RCD como insumo para estes agregados. O conceito de mineração urbana diz respeito à procura e ao processo de tratamento dos RCDs como matéria prima para o mercado de agregados reciclados que se formou no marco regulatório da resolução CONAMA 307 de 2002. Neste mercado de agregados reciclados nascente, usa-se o conceito de Indústria Recicladora Emergente para traçar as possíveis estratégias para alcançar o nível qualitativo dos produtos de indústrias recicladoras maduras, localizada nos países pós-industriais. Para dar conta da complexidade de ações da gestão dos RCDs no novo marco regulatório, empregou-se a modelagem dinâmica para os modelos de Custo Benefício em São Paulo, Macaé e Maceió e de Viabilidade da implantação de plantas de reciclagem na cidade de Macaé. A modelagem baseia-se no trabalho empírico de amostragem do RCD das três cidades brasileiras e em visitas a plantas de reciclagem no Brasil e no exterior. Os resultados obtidos mostram: 1) A heterogeneidade das cidades amostradas no tocante a qualidade do RCD originários de distintos processos de urbanização; 2) O modelo de Custo - Benefício para as três cidades mostra que os benefícios superam os custos na seguinte ordem: São Paulo, Macaé e Maceió; 3) Plantas móveis de reciclagem são mais viáveis do que as fixas na cidade de Macaé; 4) A região de São Paulo, devido ao maior volume de RCD e maiores estímulos à reciclagem, é a única entre as três que não precisa de subsídios; 5) O modelo de viabilidade mostra que a qualidade do resíduo tem considerável influência na viabilidade das empresas de reciclagem; 6) Os fatores mais sensíveis ao modelo de viabilidade são nesta ordem: o valor cobrado pelo terreno, a taxa cobrada na entrada do RCD na planta de reciclagem, os custos de operação da planta e os impostos em vigor. / The new National Policy of Solid Waste in Brazil (Política Nacional de Resíduos Sólidos) based on the law 12305/2010, allows the use of economic instruments for the strengthening of the market of recycled aggregates still nascent, where the major part of its construction and demolition waste (CD&W) is not recycled yet This work has technical roots in two knowledge fields: mining and construction. In the mining field it will be analyzed the CD&W treatment, processed as an ore. In the construction chain the focus will be at the application of the recycled aggregates obtained, that allows the valorization of the CD&W as a raw material of these aggregates. The concept of urban mining refers to the searching and the process of treating the CD&W as raw material for the market of recycled aggregates formed in the regulatory framework of CONAMA Resolution 307. In this nascent market for recycled aggregates we use the concept of recycling emerging industry and determined possible strategies to reach the quality level of the products of recycling industries located in mature post-industrial countries. To solve the complexity of the inherent management actions of CD&W in the new regulatory framework, it was employed dynamic modeling models of Cost Benefit analysis in Sao Paulo, Macaé and Maceió and also Feasibility models to implement recycling plants in the city of Macaé. The modeling is based on the empirical work of CD&W sampling of the three Brazilian cities and visits to recycling plants in Brazil and abroad. The results show: 1) The heterogeneity of the cities surveyed regarding the quality of the CD&W due to the different processes of urbanization; 2) The model of Cost - Benefit for the three cities shows that the benefits are greater than the costs in the following order: São Paulo, Macaé, Maceió; 3) In the city of Macaé, recycling mobile plants are more economic viable; 4) The region of Sao Paulo, due to higher volume and higher RCD incentives recycling, is the only one among the three which do not need subsidies; 5) The feasibility model shows that the difference in qualities of the waste has considerable influence on the viability of recycling companies; 6) The most sensitive factors in the viability model are in this order: the amount charged for the land, the tax fee into the recycling plant, the plant\'s operational costs and the taxes.
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Caracterização das propriedades de agregados miúdos reciclados e a influência no comportamento reológico de argamassas. / Characterization of properties of fine recycled aggregates and its influence on mortar rheological behavior.

Hawlitschek, Gustav 29 September 2014 (has links)
A construção civil consome uma quantidade enorme de matérias primas minerais e por consequência também gera uma grande quantidade de resíduos, denominados resíduos de construção e demolição (RCD). No Brasil a estimativa é de que são geradas mais de 70 milhões de toneladas de RCD por ano, ficando atrás apenas da produção de minério de ferro, areia e brita. A reciclagem de RCD, tanto no Brasil como em outros países, envolve basicamente etapas de britagem e peneiramento, sendo poucas as usinas que utilizam o beneficiamento mineral para a separação das fases porosas inorgânicas, as quais causam inúmeras dificuldades na utilização dos agregados reciclados como materiais de construção. Estudos recentes comprovaram a eficácia do beneficiamento mineral na produção de agregados reciclados de baixa porosidade. No entanto, a aplicação em argamassas e concretos ainda não é recomendada e tampouco regulamentada, principalmente pela ausência de procedimentos de caracterização dos produtos gerados. Nesse contexto, o presente trabalho avalia a técnica de medida de porosidade por meio de intrusão de mercúrio em agregados miúdos reciclados e a influência deste parâmetro no comportamento reológico de argamassas. Complementarmente, são também estudados o comportamento reológico de misturas cimentícias formuladas com areias com diferentes características (morfologia e porosidade). Foram utilizadas três areias recicladas com diferentes porosidades e três areias comerciais (naturais ou oriundas de britagem de rochas) de referência com diferentes formas. As areias foram caracterizadas e, posteriormente, foram utilizadas na formulação de argamassas, as quais foram avaliadas tanto no estado fresco como no endurecido. A porosimetria por intrusão de mercúrio mostrou-se uma alternativa mais rápida e precisa na determinação da porosidade de areias recicladas. Contudo, para estudos de materiais particulados de granulometria fina, abaixo de 300 m, a definição das condições operacionais torna-se determinante. Os resultados mostraram que apesar das diferentes características das areias (forma e porosidade), estas podem apresentar um comportamento reológico similar em função do teor de água e de aditivos adicionados à mistura cimentícia. Por outro lado, a porosidade dos agregados influencia diretamente nas propriedades mecânicas da mistura, pois quanto maior o consumo de água e o teor de ar incorporado, maior será a porosidade no estado endurecido e, consequentemente, menor sua resistência à compressão. Sendo assim, o estabelecimento do equilíbrio entre o investimento em tecnologias de processamento mineral para redução da porosidade ou a tolerância ao aumento no consumo de água e aditivos está mais diretamente relacionado à viabilidade econômica do que técnica. Uma alternativa ao beneficiamento mineral após a britagem, seria a substituição parcial dos agregados naturais pelos reciclados; com isso, tem-se uma redução da porosidade total da mistura e a incorporação parcial de agregados reciclados, com mínima intervenção no sistema. / The construction industry consumes an enormous amount of mineral raw materials and consequently also generates lots of waste, known as construction and demolition waste (CDW). In Brazil, it is estimated that over 70 million tons of CDW are generated per year, which is equivalent to the fourth position in national ranking of mineral commodities production. Recycling of CDW, in Brazil and in other countries, basically involves crushing and screening stages. Few plants uses mineral processing for the separation of inorganic porous phases, responsible for many limitations on recycled aggregates application as construction material. Recent studies have proven the effectiveness of mineral beneficiation in the production of low porosity recycled aggregates. However, application in mortar and concrete is still not recommended nor regulated, mainly by the absence of characterization procedures of generated products. In this context, this research evaluates the mercury intrusion porosity technique for characterization of recycled fine aggregates and the influence of this parameter on the rheological behavior of mortars. Additionally, the rheological behavior of mortars composed with fine aggregates with different characteristics (morphology and porosity) are also studied. Recycled sands with three different porosities and three commercial sands (natural or produced by rocks crushing) with different shapes were used. The sands were characterized and used on mortars composition, which were analyzed in fresh and hardened state. The mercury intrusion porosimetry proved to be a faster and accurate method in determining the porosity of recycled sands. However, the operations conditions and experimental procedure for the characterization of fine particulate materials, mainly below 300 m, plays a major role for reproducible results. The results showed that despite the different sands features (porosity and shape), they may have similar rheological behavior as a function of water content and additives added to the mortars. Aggregates porosity influences directly the mechanical properties of the mortar, the higher the water consumption and air content, the higher the porosity in the hardened state and consequently the lower the compression resistance. Thus, the establishment of the equilibrium between the investments in mineral processing technologies to reduce the aggregates porosity or the tolerance for increasing water and additives consumption is more related to the economic viability than technically. An alternative to mineral beneficiation after crushing would be the partial replacement of natural aggregates by recycled ones, this will lead to a lower porosity system with partial incorporation of recycled aggregates.

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