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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.
151

Exploring Lean Practices in Commercial Construction Projects / Utforskning av leanverktyg i kommersiella byggprojekt

Shakarchi, Ahmad, Fadhil, Daniel January 2021 (has links)
Lean construction is often suggested as way of enhancing the productivity of the construction industry. There are no clear definitions of lean construction, but it is often referred to as a construction management philosophy that aims to minimize waste and maximise customer value. Adopting lean construction in a project can be difficult and there are several critical factors for successful implementation; one of which is the use of lean construction practices. Lean construction practices are tools, techniques and strategies through which the principles of lean construction can be implemented. It has been pointed out that there is lack of information on the number of existing practices and their exact area of use. This master thesis report identified lean practices that have been implemented in commercial construction projects, and categorised them according to the phases of lean construction. The report also explored which lean production-planning-and-control- practices have been adopted by a commercial construction contractor. To identify the lean practices, a literature analysis was conducted based on the documents reviewed by Babalola et al. (2019) in their article ‘Implementation of lean practices in the construction industry: A systematic review’. This revealed 22 different lean practices that have been implemented in commercial construction projects, with the Last Planner System having been reported the most followed by Just in Time and Pull Scheduling. The literature analysis also resulted in the project delivery stages in which each identified practice had been adopted. This helped categorise the practices according to the phases of lean construction. The phases were defined by the conceptual framework ‘The Lean Project Delivery System’ as Project Definition, Lean Design, Lean Supply, Lean Assembly and Lean Use. The categorisation showed that (out of the 22 identified practices) 3 practices belong to the phase Project Definition, while 8, 9, 15 and 0 practices belong to the other phases respectively. To explore which lean production-planning-and-control-practices have been adopted by a commercial construction contractor, a case study was conducted of the production phase of a large-sized project referred to as Project X. Seven members of the production team were interviewed as to reveal the contractor’s working methods in the planning and control of production in terms of time, activity and logistics. The revealed working methods were then compared to 9 out of the 22 identified lean practices, since they were interpreted as production-planning-and-control-practices. This analysis showed that six of those practices were seemingly implemented in the production of Project X, while one was partially implemented and two were not implemented. / Lean byggproduktion föreslås ofta som ett sätt att öka produktiviteten i byggbranschen. Det finns inga tydliga definitioner av lean byggproduktion, men konceptet beskrivs ofta som en filosofi för byggledning som ämnar minimera avfall och maximera kundvärdet. Att anta lean byggproduktion i ett projekt kan vara svårt och det finns ett antal kritiska faktorer för lyckad implementering, varav en är användandet av lean byggverktyg. Lean byggverktyg är verktyg, tekniker och strategier genom vilka principerna av lean byggproduktion kan implementeras. Det har påpekats att det finns brist på information om antalet befintliga lean byggverktyg och deras användningsområden. Denna rapport identifierade lean verktyg som har implementerats i kommersiella byggprojekt, och kategoriserade de enligt faserna av lean byggproduktion. Rapporten utforskade också vilka lean verktyg för planering och styrning av produktion som har antagits av en kommersiell byggentreprenör. För att identifiera leanverktyg i kommersiella byggprojekt så genomfördes en litteraturanalys baserat på de dokument som granskats av Babalola et al. (2019) i deras artikel ‘Implementation of lean practices in the construction industry: A systematic review’. Detta avslöjade 22 olika lean byggverktyg som implementerats i diverse kommersiella byggprojekt, där Last Planner System har rapporterats mest följt av Just in Time och Pull Scheduling. Litteraturanalysen resulterade också i projektleveransstadierna där varje identifierat verktyg hade implementerats. Detta hjälpte att kategorisera verktygen enligt faserna av lean byggproduktion. Faserna definierades av det konceptuella ramverket ’The Lean Project Delivery System’ som Project Definition, Lean Design, Lean Supply, Lean Assembly och Lean Use. Kategoriseringen visade att (utav de 22 identifierade verktygen) 3 verktyg tillhör fasen Project Definition, medan de resterande faserna innefattar 8, 9, 15 respektive 0 verktyg. För att utforska vilka lean verktyg för planering och styrning av produktion som har antagits av en kommersiell byggentreprenör så utfördes en fallstudie av produktionsfasen av ett stort projekt såkallat Projekt X. Sju medlemmar av produktionsteamet intervjuades för att uppenbara entreprenörens arbetsmetoder vid planering och styrning av produktion beträffande tid, aktivitet och logistik. De uppenbarade arbetsmetoderna jämfördes sedan med 9 av de 22 identifierade leanverktygen eftersom just de tolkades som verktyg för planering och styrning av produktion. Denna analys visade att sex av dessa verktyg var till synes implementerade i produktionen av Projekt X, medan en var delvis implementerad och två inte alls implementerade.
152

Práticas de produção enxuta no contexto da construção e manutenção de redes de distribuição de utilidades. / Lean production practices in the context of construction and maintenance of utility distribution networks.

Kempenich, Sergio 21 October 2009 (has links)
Esta dissertação considera a atuação das empresas responsáveis pelas redes de distribuição de água, energia elétrica e gás natural denominadas Redes de Distribuição de Utilidades (RDUs) como sistemas produtivos, com o propósito de conhecer e avaliar a maneira como os esforços de melhoria da produtividade são conduzidos em busca de metas como maior qualidade, menor custo e menor prazo de entrega ao cliente. Este estudo é desenvolvido tomando-se como referência o modelo da produção enxuta, desenvolvido pela Toyota Motor Company do Japão, fundamentado no princípio de buscar o aumento da produtividade por meio da identificação e eliminação de desperdícios. Embora originalmente disseminada na cadeia da indústria automobilística, a adoção e adaptação da abordagem de melhoria de processos deste modelo têm sido consideradas em diferentes setores. Assim, o presente trabalho tem como motivação explorar as possibilidades de estender a aplicação de conceitos e práticas da produção enxuta em empresas de RDU. Primeiramente, a cadeia de valor das RDUs é analisada, e são escolhidos dois processos construção e manutenção para o desenvolvimento do estudo. Em seguida, é apresentada uma revisão bibliográfica, a partir da qual um conjunto de dezenove práticas enxutas possivelmente aplicáveis aos processos escolhidos é identificado. Por meio de três estudos de caso, analisa-se em que medida as empresas responsáveis pelas RDUs aplicam tais práticas enxutas em seus processos, e em que medida a aplicação atual ou uma possível aplicação futura de cada prática enxuta é motivada pelo pensamento enxuto. Com base nos dados levantados na pesquisa de campo, as práticas consideradas são avaliadas quanto ao potencial de efetiva aplicação em cada processo, levando-se em conta o objetivo de eliminação de desperdício. O estudo possibilitou verificar que todas as dezenove práticas são aplicáveis a pelo menos um dos processos considerados, sendo a maioria aplicável a ambos. / This dissertation considers the performance of the companies that are responsible for water, electricity and natural gas networks named Utility Distribution Networks (UDN) as productive systems, in order to understand and evaluate the way that the efforts for continuous productivity improvement of their processes are conducted in search of goals such as more quality, less cost and less lead time to customer. The model that is used as a reference for this study is the lean production model, which was developed by the Toyota Motor Company in Japan, founded on the principle of search for productivity increase by the elimination on waste. Although it was originally disseminated in the auto industry value chain, the process improvement approach from this model has been considered in different industries. Therefore, the present work is motivated by the chance to explore the possibility of extending the lean production application concepts and practices to UDN companies. Firstly, UDNs value stream is analyzed, and two processes are chosen construction and maintenance for the development of study. Then, a bibliographic review is presented, from which a set of nineteen lean practices that maybe possibly applicable on the chosen processes is identified. By the development of three case studies, an evaluation is performed with the objective to analyze to what extent the companies that are responsible for UDN apply those lean practices on their processes, and to what extent the current application or a possible future application of each lean practice is motivated by lean thinking. Based on the data from the field research, the potential for effective application of the considered practices is evaluated for each process, taking into consideration the objective of elimination of waste. The study made it possible to verify that all the nineteen practices are applicable at least on one of the considered processes, and the majority is applicable on both processes.
153

Hantering av oanvänt byggmaterial på byggarbetsplatser / Management of unused construction material on construction sites

Alsterlund, Karin, Andler, Fanny January 2018 (has links)
Syfte: Byggindustrin genererar över 100 miljoner ton avfall per år. Fokus vid miljöarbete ligger ofta på materialval, energianvändning, inomhusmiljö, transporter och avfall. Med hjälp av certifieringssystem kan byggnader klassificeras och för att uppnå certifieringarna finns vissa krav. Det finns dock inga krav när det gäller kassering av oanvänt byggmaterial. 13 procent av avfallet är så kallat oanvänt material. Med oanvänt material menas material och produkter som beställs till ett byggprojekt men inte nyttjas under byggnationen utan hamnar i containern. Målet med arbetet är därför att undersöka hur kasseringen kan minska av oanvänt material på stora byggföretag i Sverige. Metod: Arbetet genomfördes som en kvalitativ studie där metoderna litteraturstudie, dokumentanalys och intervjuer har använts. Litteraturstudien kartlade dagens forskningsfront. Dokumentanalysen och intervjuerna gav information om företagets miljömål, etiska regler och arbetssätt. Resultat: Arbetet visar att oanvänt material förekommer p.g.a. bristfällig mängdning till följd av tidsbrist och oro över att få stillestånd. Det förekommer även då hanteringen av materialet på arbetsplatser leder till skador som gör att det kasseras. Materialet kasseras för att följa företagets etiska regler men motstrider de uppsatta miljömålen. Samtliga intervjurespondenter var eniga om att en förändring behövs för att få ett mer hållbart byggande. Resultatet visar att företaget har ett framarbetat arbetssätt, samlastning, som skulle kunna användas i större utsträckning för att minska kasseringen av oanvänt material på fler arbetsplatser. Det framkom även att oanvänt material kan tillvaratas på ett bättre sätt genom mer kommunikation mellan projekten för att möjliggöra nyttjandet av det överblivna materialet på ett annat projekt. Problematiken med hanteringssättet är variationen av entreprenadform på projekten då det inte alltid är företaget som äger materialet. En säljportal har tidigare diskuterats i företaget men där är platsbrist och resursåtgång problematiskt. Material förblir oanvänt p.g.a skador orsakade av väder men platsbrist på projekten orsakar att extra väderskydd inte är en genomförbar lösning. Konsekvenser: För att minska uppkomsten av oanvänt material kan BIM, Lean, prefabricering och samlastning användas. För att nyttja material som blir oanvänt kan bättre kommunikation mellan projekten gynna material kasseringen. Begränsningar: Arbetet har avgränsat genom att endast teoretiskt undersöka hur kasseringen av material kan minska. Inga mätningar har genomförts. Varken tid ekonomiska aspekter har undersökts. Arbetet anser inte material som spill, förbrukningsmaterial eller material som vid rivning är användbart utan enbart oanvänt material vid nybyggnation. Resultatet är brukbart för större företag eftersom mindre företag inte har samma problematik. Nyckelord: Avfall och energiutsläpp minskning, Building Information Modeling, BIM, etiska regler, hållbarhet, kassering, Lean Construction, materialavfall, materialhantering,  miljö, miljömål, oanvänt byggmaterial, samlastning. / Purpose: The construction industry generates over 100 million ton of waste every year. When it comes to sustainability there is focus on material type, energy use, indoor climate, transports and waste. There are different certification systems that can be used to classify the buildings. In those certification systems there are no requirements on unused building material. 13 percent of the waste contains unused material. Unused material means material and products that are ordered to the construction site but is not used in the construction. The goal with the project is to analyse how to reduce the amount of unused material that goes to waste on big construction companies in Sweden. Method: This thesis is done through a qualitative study with the methods of literature study, document analysis and interviews. The literature study showed the current research front. Document analysis and interviews provided information about the companies sustainable goals, ethical regulations and working methods. Findings: The thesis shows that unused material occurs because of difficulties to quantify material because of the tight time schedule and not wanting to risk getting downtime in the production. The material gets damaged when it is handled on the construction site. The material is disposed to follow the ethical requirements of the company but is not in line with the sustainability goals. All interview responders agreed on the need of change to achieve the goal. The company has a working method where the trucks drive the material to a terminal and then out to the construction when it is time for the material to be used. This method could be used to minimize the disposal. Better communication between the projects would help unused material to be taken care of in a different project. The problem is that since it is different owners of the material depending on the purchase of contract it is not always easy to handle the material between the projects. To sell the unused material has been discussed before in the company but because of the lack of space and resource consumption it is problematic. Material also get damaged from the weather, but the lack of space is the reason why a tent not is a good solution. Implications: In order to reduce the occurrence of unused material, BIM, Lean, prefabrication and terminal management can be used. The materials that become unused can be taken care of in a different project, better communication between the projects will reduce material disposal. Limitations: The thesis is only theoretically analysing how to reduce disposal of unused material. No measures of time or economical aspects has been analysed. The work does not consider material like waste, consumables or material that are useable after demolishes. The result is useful in larger companies since smaller companies do not have the same problematics. Keywords: Building Information Modeling, BIM, disposal,  durability, environment, environmental objectives,  ethical rules, Lean Construction, material handling,  material waste, terminal management, unused building materials, waste and energy loss reduction.
154

Propostas Logísticas para o Suprimento de Estruturas Metálicas Utilizando Ferramentas Lean / Logistics proposals for the supply of metalic structures using lean tools

Paulo Roberto Corrêa de Araújo 14 December 2005 (has links)
Este trabalho propõe uma organização para o processo de abastecimento de estruturas metálicas na construção de um prédio comercial, correlacionando a logística de suprimento do canteiro com a montagem das estruturas metálicas. A proposta foi desenvolvida a partir dos conceitos da logística empresarial e da concepção construtiva lean originário do Sistema Toyota de Produção e, posteriormente, foram aplicados em outros setores como o da construção civil. Para enfatizar problemas críticos do processo abastecimento de materiais e identificar suas soluções, foi estudada uma proposta logística para o suprimento das estruturas em uma obra localizada no Centro da cidade do Rio de Janeiro. A sincronização entre a atividade logística e o processo de montagem das estruturas seguiu a lógica lean de redução de tempos de espera, de eliminação de estoques em canteiro, como condição para a melhoria de produtividade da obra. Foi analisado o mapeamento da cadeia de valor do fluxo de materiais e operações compreendidos entre o depósito de estruturas e a obra, verificando o balanceamento de atividades de produção e os possíveis ganhos de produtividade. Os resultados obtidos evidenciariam potencial de ganho na medida em que fornece justificativas para a aplicação das atividades logísticas e das ferramentas lean na proposta de suprimento de estruturas. A proposta logística apresentada integra os fabricantes de estruturas com a obra e principalmente reduz as esperas e estoques em processo, que são considerados desperdícios na concepção construtiva lean. Conclui-se, portanto, que a logística é fator decisivo na viabilidade de qualquer processo construtivo, e que, especificamente, sob os conceitos do sistema de construção lean, reúne condições para a melhoria de produtividade do processo construtivo e por conseguinte aumento de competitividade. / In this Work is proposed the organization for structural steel supply process in the construction of a commercial building, correlating the supply logistic of the site with the assembly of the steel structures. The proposal was developed using the concepts of business logistic and of the original lean construction conception that was developed by Toyota Production system and later applied in other sections as the one of the building site. In order to emphasize critical problems of the provisioning process of materials and to identify there the main solutions, it was studied a logistic proposal for the supply of the structures in a located work downtown of Rio de Janeiro. The synchronization between the logistics activity and the structures assembly process followed the lean logic of reduction of wait time, of elimination of stocks in construction site, as condition for the improvement of the productivity of construction. It was analyzed the value stream mapping of the materials flow and operations understood between the structures warehouse and the construction site, verifying the swinging of production activities and the possible productivity gains. The obtained results would evidence potential earnings in the measure that it supplies justifications for the application of logistics activities and of the lean tools for structural steel supply. The proposal presented logistic integrates the manufacturers of structures with the work and mainly it reduces the waits and stocks in process, that wastes are considered in lean constructive conception. We can conclude that the logistic is a decisive factor in the viability of any construction process, and that, specifically, under the concepts of lean construction system, it gathers conditions for the improvement of productivity of the constructive process and consequently increase of competitiveness.
155

Propostas Logísticas para o Suprimento de Estruturas Metálicas Utilizando Ferramentas Lean / Logistics proposals for the supply of metalic structures using lean tools

Paulo Roberto Corrêa de Araújo 14 December 2005 (has links)
Este trabalho propõe uma organização para o processo de abastecimento de estruturas metálicas na construção de um prédio comercial, correlacionando a logística de suprimento do canteiro com a montagem das estruturas metálicas. A proposta foi desenvolvida a partir dos conceitos da logística empresarial e da concepção construtiva lean originário do Sistema Toyota de Produção e, posteriormente, foram aplicados em outros setores como o da construção civil. Para enfatizar problemas críticos do processo abastecimento de materiais e identificar suas soluções, foi estudada uma proposta logística para o suprimento das estruturas em uma obra localizada no Centro da cidade do Rio de Janeiro. A sincronização entre a atividade logística e o processo de montagem das estruturas seguiu a lógica lean de redução de tempos de espera, de eliminação de estoques em canteiro, como condição para a melhoria de produtividade da obra. Foi analisado o mapeamento da cadeia de valor do fluxo de materiais e operações compreendidos entre o depósito de estruturas e a obra, verificando o balanceamento de atividades de produção e os possíveis ganhos de produtividade. Os resultados obtidos evidenciariam potencial de ganho na medida em que fornece justificativas para a aplicação das atividades logísticas e das ferramentas lean na proposta de suprimento de estruturas. A proposta logística apresentada integra os fabricantes de estruturas com a obra e principalmente reduz as esperas e estoques em processo, que são considerados desperdícios na concepção construtiva lean. Conclui-se, portanto, que a logística é fator decisivo na viabilidade de qualquer processo construtivo, e que, especificamente, sob os conceitos do sistema de construção lean, reúne condições para a melhoria de produtividade do processo construtivo e por conseguinte aumento de competitividade. / In this Work is proposed the organization for structural steel supply process in the construction of a commercial building, correlating the supply logistic of the site with the assembly of the steel structures. The proposal was developed using the concepts of business logistic and of the original lean construction conception that was developed by Toyota Production system and later applied in other sections as the one of the building site. In order to emphasize critical problems of the provisioning process of materials and to identify there the main solutions, it was studied a logistic proposal for the supply of the structures in a located work downtown of Rio de Janeiro. The synchronization between the logistics activity and the structures assembly process followed the lean logic of reduction of wait time, of elimination of stocks in construction site, as condition for the improvement of the productivity of construction. It was analyzed the value stream mapping of the materials flow and operations understood between the structures warehouse and the construction site, verifying the swinging of production activities and the possible productivity gains. The obtained results would evidence potential earnings in the measure that it supplies justifications for the application of logistics activities and of the lean tools for structural steel supply. The proposal presented logistic integrates the manufacturers of structures with the work and mainly it reduces the waits and stocks in process, that wastes are considered in lean constructive conception. We can conclude that the logistic is a decisive factor in the viability of any construction process, and that, specifically, under the concepts of lean construction system, it gathers conditions for the improvement of productivity of the constructive process and consequently increase of competitiveness.
156

Práticas de produção enxuta no contexto da construção e manutenção de redes de distribuição de utilidades. / Lean production practices in the context of construction and maintenance of utility distribution networks.

Sergio Kempenich 21 October 2009 (has links)
Esta dissertação considera a atuação das empresas responsáveis pelas redes de distribuição de água, energia elétrica e gás natural denominadas Redes de Distribuição de Utilidades (RDUs) como sistemas produtivos, com o propósito de conhecer e avaliar a maneira como os esforços de melhoria da produtividade são conduzidos em busca de metas como maior qualidade, menor custo e menor prazo de entrega ao cliente. Este estudo é desenvolvido tomando-se como referência o modelo da produção enxuta, desenvolvido pela Toyota Motor Company do Japão, fundamentado no princípio de buscar o aumento da produtividade por meio da identificação e eliminação de desperdícios. Embora originalmente disseminada na cadeia da indústria automobilística, a adoção e adaptação da abordagem de melhoria de processos deste modelo têm sido consideradas em diferentes setores. Assim, o presente trabalho tem como motivação explorar as possibilidades de estender a aplicação de conceitos e práticas da produção enxuta em empresas de RDU. Primeiramente, a cadeia de valor das RDUs é analisada, e são escolhidos dois processos construção e manutenção para o desenvolvimento do estudo. Em seguida, é apresentada uma revisão bibliográfica, a partir da qual um conjunto de dezenove práticas enxutas possivelmente aplicáveis aos processos escolhidos é identificado. Por meio de três estudos de caso, analisa-se em que medida as empresas responsáveis pelas RDUs aplicam tais práticas enxutas em seus processos, e em que medida a aplicação atual ou uma possível aplicação futura de cada prática enxuta é motivada pelo pensamento enxuto. Com base nos dados levantados na pesquisa de campo, as práticas consideradas são avaliadas quanto ao potencial de efetiva aplicação em cada processo, levando-se em conta o objetivo de eliminação de desperdício. O estudo possibilitou verificar que todas as dezenove práticas são aplicáveis a pelo menos um dos processos considerados, sendo a maioria aplicável a ambos. / This dissertation considers the performance of the companies that are responsible for water, electricity and natural gas networks named Utility Distribution Networks (UDN) as productive systems, in order to understand and evaluate the way that the efforts for continuous productivity improvement of their processes are conducted in search of goals such as more quality, less cost and less lead time to customer. The model that is used as a reference for this study is the lean production model, which was developed by the Toyota Motor Company in Japan, founded on the principle of search for productivity increase by the elimination on waste. Although it was originally disseminated in the auto industry value chain, the process improvement approach from this model has been considered in different industries. Therefore, the present work is motivated by the chance to explore the possibility of extending the lean production application concepts and practices to UDN companies. Firstly, UDNs value stream is analyzed, and two processes are chosen construction and maintenance for the development of study. Then, a bibliographic review is presented, from which a set of nineteen lean practices that maybe possibly applicable on the chosen processes is identified. By the development of three case studies, an evaluation is performed with the objective to analyze to what extent the companies that are responsible for UDN apply those lean practices on their processes, and to what extent the current application or a possible future application of each lean practice is motivated by lean thinking. Based on the data from the field research, the potential for effective application of the considered practices is evaluated for each process, taking into consideration the objective of elimination of waste. The study made it possible to verify that all the nineteen practices are applicable at least on one of the considered processes, and the majority is applicable on both processes.
157

Desenvolvimento técnico e avaliação de custo e benefício do sistema construtivo de painéis sanduíche, com núcleo de garrafas PET, moldados no local / Technical development and evaluation od cost and benefit of the construction system of sandwich panels, with bottles PET nuccleus, framed in local

Fernandes, Georgeo Dias 28 January 2016 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-01T09:08:49Z No. of bitstreams: 2 Dissertação - Georgeo Dias Fernandes - 2016.pdf: 4550829 bytes, checksum: c89172b3acd5d16ace7d0bf283fc8446 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-01T09:10:55Z (GMT) No. of bitstreams: 2 Dissertação - Georgeo Dias Fernandes - 2016.pdf: 4550829 bytes, checksum: c89172b3acd5d16ace7d0bf283fc8446 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-01T09:10:55Z (GMT). No. of bitstreams: 2 Dissertação - Georgeo Dias Fernandes - 2016.pdf: 4550829 bytes, checksum: c89172b3acd5d16ace7d0bf283fc8446 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2016-01-28 / Traditional construction methods are questioned, because of low productivity, waste, rework, low standardization, among other things. Because of these problems and taking into account environmental aspects, new building systems that make use of reusable or recyclable materials from other industries are analyzed to verify its efficiency in technical and economic level. In this context, the aim of the dissertation is to describe the technical development and assess costs and benefits of the constructive system sandwich panels, molded on site, which reuses bottles of polyethylene terephthalate (PET) to make up the core of the walls and slabs. Concerning the technical development was described experiments and tests carried out for the conformation of the construction system, with the configuration of its characteristics and peculiarities, discussed the results of the tests performed, including the early to define the structural safety of the walls and slabs together with the presentation of the theoretical model calculation and performance evaluation for the validation. In the economic aspect, there was a comparison between the traditional construction system and the studied system. The cost direct was examined and observed the benefits with the help of value attributes expected to prefabricated options construction, drawn by Cook (2013), namely: direct costs (material and labor), time (schedule), design flexibility, work time management, quality, delivery and conference in work, subcontractors activities in work, work safety, exercise stress testing, health, environmental impact, LEED certification, rubble and dispensing, public relations, marketing, maintenance (life cycle). With the help of estimators engineers, through interviews, the steps we investigated, activities, productivity and resources needed to execute a project in the traditional building system, building system in masonry traditional system and building system analyzed. Was elaborated cost composition of spreadsheets and productivity for hypothetical situations of conventional and innovative construction system of sealing walls with slabs of residential buildings and walls and structural slabs works until two floors. The mapping process was designed, in which to extract the consideration of potential benefits or otherwise of the building system. Technical descriptions highlight the possibility of constructive feasibility of sandwich panels, with core of PET bottles, molded on site. And the evaluation of costs and benefits demonstrates its value, not so much due to the direct cost, but in terms of building system management benefits. / Os métodos construtivos tradicionais são questionados em função da baixa produtividade, desperdícios, retrabalhos e baixa padronização, dentre outros aspectos. Em virtude destes problemas e levando em conta aspectos ambientais, novos sistemas construtivos, que fazem uso de materiais reutilizáveis ou recicláveis de outras indústrias, são analisados visando verificar sua eficiência em nível técnico-econômico. Diante desse contexto, o objetivo da dissertação é descrever o desenvolvimento técnico e avaliar custo e benefício do sistema construtivo em painéis sanduíche, moldados no local, que reutiliza garrafas de politereftalato de etileno (PET) para compor o núcleo das paredes e lajes. Relativo ao desenvolvimento técnico, descrevem-se os experimentos e ensaios realizados para a conformação do sistema construtivo, apresentando a configuração das suas características e peculiaridades. Em seguida, discutem-se os resultados dos ensaios executados, compreendendo os iniciais para definição da segurança estrutural das paredes e lajes conjuntamente com a apresentação do modelo teórico de cálculo, bem como os de avaliação de desempenho para validação. No aspecto econômico, faz-se um comparativo entre o sistema construtivo tradicional e o sistema estudado. A relação custo direto foi examinada e observou-se os benefícios com a ajuda dos atributos de valor esperados para opções pré-fabricadas de construção, quais sejam: custo direto (material e mão de obra), tempo (cronograma), flexibilidade de projeto, tempo de administração de obra, qualidade, entregas e conferência em obra, atividades de subempreiteiros em obra, segurança do trabalho, ergometria, condições de saúde, impacto ambiental, certificação LEED, entulho e descarte, relações públicas, marketing e manutenção (ciclo de vida). Com a ajuda de engenheiros orçamentistas, por meio de entrevistas, investigaram-se as etapas, atividades, produtividade e recursos necessários para executar um projeto no sistema construtivo tradicional, sistema construtivo em alvenaria estrutural e no sistema construtivo analisado. Elaboraram-se planilhas de composição de custo e produtividade para as situações hipotéticas do sistema construtivo inovador e convencional de paredes de vedação com lajes de edifícios habitacionais e para paredes e lajes estruturais de obras até dois pavimentos. O mapeamento dos processos foi delineado, no qual foram extraídas as considerações sobre possíveis benefícios ou não do sistema construtivo. As descrições técnicas evidenciam a possibilidade da viabilidade construtiva de painéis sanduíche, com núcleo de garrafas PET, moldados no local. Já o a avaliação de custo e benefício demonstrou seu valor, nem tanto em função do custo direto, mas, em termos de benefícios de gestão do sistema construtivo.
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Planificación y Programación para la Construcción de una Estación de Tren Subterránea de la Línea 2 del Metro de Lima y Callao, Aplicando la Metodología Lean Construction para el Control y Ejecución del Proyecto

Velásquez Luque, Humberto Martín Ernesto 23 November 2020 (has links)
La filosofía Lean Construction (LC) o la construcción sin pérdida se da en la década de 1990, siendo este una adaptación del modelo automovilístico del Toyota Production System o Lean Production a la industria de la construcción, la introducción o el nuevo enfoque de la gestión de proyectos de construcción fue propuesta por el profesor Lauri Koskela, donde nos dice que veamos a la producción en la construcción como un proceso de transformación, de flujo y generador de valor, en consecuencia el objetivo de LC es crear buenos sistemas de producción que permitan optimizar, reducir o eliminar los flujos para mejorar los tiempos de entrega. El sector construcción uno de los más importantes gestores de la economía del país por su participación del PBI necesita la aplicación de metodologías en la gestión de proyectos como LC para generar valor sin pérdidas, sin embargo, su aplicación o su correcta aplicación es reducida, resultando con indicadores óptimos para un grupo selecto de empresas de construcción. En este trabajo de investigación se va a proponer la aplicación de la filosofía Lean Construction como herramienta para la planificación, ejecución y control para la construcción de una estación subterránea de pasajeros para la Línea 2 del Metro de Lima y Callao, vamos a detallar los conceptos y herramientas del LC que, nos sirvan como base para su aplicación y desarrollo para el cumplimiento de los objetivos del proyecto. Así también, se determinará la secuencia, división y sectorización de trabajo para la elaboración del plan de trabajo, se identificarán las actividades que no agregan valor o no productivas, atacando así las perdidas más visibles, reduciendo los ciclos y proponiendo actividades en paralelo. Aplicaremos las teorías Last Planner, Lookahead y Week Planning para el control del proyecto a fin de evaluar restricciones y determinar los que podemos hacer en la planificación diaria, con lo cual buscamos generar una guía para la ejecución del resto de estaciones que comprenden el proyecto. Finalmente se analizará los resultados del proyecto mediante herramientas de medición como el PAC (Porcentaje de Actividades Cumplidas), TC (trabajos contributorios) y otros para las conclusiones y recomendaciones para futuras estaciones aplicando la mejora continua. / The Lean Construction (LC) philosophy or construction without loss occurred in the 1990s, this being an adaptation of the automotive model of Lean Production to the construction industry, the introduction or the new approach to construction project management It was proposed by Professor Lauri Koskela, where he tells us to see production in construction as a process of transformation, flow and value generator, therefore the objective of LC is to create good production systems that allow optimizing, reducing or eliminate flows to improve delivery times. The construction sector, one of the most important managers of the country's economy due to its participation in GDP, needs the application of project management methodologies such as LC to generate value without losses, however its application or its correct application is reduced, resulting in Optimal indicators for a select group of construction companies. In this thesis, the application of the Lean Construction philosophy will be proposed as a tool for planning, executing and controlling the construction of an underground passenger station for Line 2 of the Lima and Callao Metro, we will detail the concepts and tools of the LC that serve as a basis for its application and development for the fulfillment of the project's objectives. Also, the sequence, division and sectorization of work for the preparation of the work plan will be determined, activities that do not add value or are not productive will be identified, thus attacking the most visible losses, reducing cycles and proposing activities in parallel. We will apply Last Planner, Lookahead and Week Planning theories for project control in order to evaluate restrictions and determine what we can do in daily planning, with which we seek to generate a guide for the execution of the rest of the stations that comprise the project. Finally, the results of the project will be analyzed using measurement tools such as the PAC (Percentage of Completed Activities), TC (contributory works) and others for the conclusions and recommendations for future stations applying continuous improvement. / Tesis
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Förstärkning av träregelstomme med KL-trä : Teoretisk utvärdering av olika ytterväggstyper / Strengthening of light frame timber walls with CLT : Evaluation of different wall types

Larsson, Joel January 2020 (has links)
På senare tid har intresset för och viljan att bygga flerbostadshus i trä ökat och medfört en trend att bygga allt högre hus med stomme av trä. En aktör är Lindbäcks Bygg som bygger flerbostadshusi trä med volymelement och lätt regelstomme. Idag begränsas dock möjligt antal våningar med regelstomme till 6 – 8 våningar. Ett relativt nytt material inom träbyggnadstekniken är korslimmat trä (KL-trä) vars användning gjort det möjligt att bygga högre byggnader i trä. Examensarbetets syfte är att studera olika lösningar för hur Lindbäcks regelstomme kan förstärkas med KL-trä, vilket kan göra det möjligt att bygga allt högre flerbostadshus i trä. Samt att jämföra denna lösning med den idag använda regelstommen utan KL-trä. Studien har avgränsats till att enbart behandla ytterväggar. För att uppskatta rimliga laster på ytterväggar i en flervåningsbyggnad togs en principbyggnad (ihopsatt av ett antal volymelement) fram. I beräkningar tillämpades ett antal olika ytterväggstyper, en med den idag användaregelstommen (referensvägg) samt fem med regelstomme i kombination med KL-skivor i olika tjocklekar. För principbyggnaden kontrollerades genom beräkningar hur högt det är möjligt att bygga vid tillämpning av vardera ytterväggstyp. De olika ytterväggstyperna med KL-trä jämfördes även med referensytterväggen utifrån U-värde samt kostnad. Idag används KL-trä ibland av Lindbäcks och då som stabiliserande väggar. I deras fabriker tillämpas en lösning där KL-träskivorna fälls in mellan syll och hammarband tillsammans med reglarna. Beräkningar har visat att det, för principbyggnaden, med denna lösning är möjligt att bygga maximalt 2 våningar högre jämfört med referensytterväggen, detta för den bästa av ytterväggstypernaförstärkta med KL-trä. Det som begränsar ett högre antal våningar är trycket vinkelrätt fiberriktningen på syllen under KL-skivorna. Beräkningar visar att det finns en potential att med regelstomme förstärkt med KL-trä kunna bygga ännu högre om en annan lösning används där KL-träskivorna placeras på utsidan av syll, hammarband och reglar istället för infälld mellan syll och hammarband. Med denna lösning undviks tryck vinkelrätt fiberriktningen på syll under KL-skivor och KL-skivans kapacitet kan utnyttjas effektivare då normalkraftskapaciteten för själva skivan blir den begränsande faktorn för hur högt det går att bygga. Enligt beräkningar är det, för principbyggnaden, med denna lösning möjligt att bygga uppemot 8 våningar högre än med referensytterväggen. När KL-trä används i stommen ökar energiförlusterna genom väggen, dvs. U-värdet ökar, då reglar med mellanliggande isolering ersätts av KL-trä med sämre värmeledningsförmåga. Enligt beräkningar uppskattas U-värdet öka jmf. med för referensyttervägg, detta med ca. 20 – 40 % beroende på ytterväggstyp. Ökningen kan dock begränsas till ca. 0,4 – 14 % genom införande av ett 45 mm installationsskikt med isolering på väggens insida. Även kostnaden för ytterväggstyper med regelstomme förstärkt med KL-trä uppskattas öka jmf. med uppskattad kostnad för referensyttervägg. Detta med uppskattningsvis 40 – 50 %, vilket till huvudsak är en följd av ökad materialkostnad för KL-skivor som delvis ersätter reglar med mellanliggande isolering. / Today there is an increased interest in building taller buildings with timber. Lindbäcks Bygg is one of companies that uses modular construction with light timber stud frames. However, a problem with light timber frames is that the building height is limited to roughly 6 - 8 stories. A relatively new product in timber engineering is cross laminated timber (CLT) and the use of this product have made it possible to build taller timber buildings. The purpose of this study is to investigate different solutions for how Lindbäcks can strengthen their stud frames by using CLT and thereby build taller buildings. The difference with respect to U-value and cost between the walls strengthened width CLT and the typical stud frame wall, that is used today, is also studied. The study has been limited to exterior walls only. A multi-storey building consisting of several modules/volume elements has been used to estimate reasonable loads on the exterior walls. Different wall types, one with the ordinary stud frame (the reference wall) and five types of stud walls strengthened with different thicknesses of CLT, have been investigated. The maximal number of storeys that can be build, the U-value and the cost were determined by calculations for each of the studied wall types and were compared with the results for the reference wall. Today, Lindbäcks Bygg sometimes uses CLT for stabilizing walls. In their factories, they use a solution in which the CLT-plate is placed between the top and bottom plate together with the studs. According to the calculations it is, with this solution, possible to build up to 2 storeys higher then with the reference wall. The limiting factor for how high it is possible to build, is compression perpendicular to the grain on the bottom plate underneath the CLT-plate. If a solution where the CLT-plate is placed on the outside of the frame (consisting of studs, top and bottom plate) is used instead of between the top and bottom plate does the calculations show that a higher number of storeys is possible. With this solution, the compression perpendicular to the grain underneath the CLT-plate is avoided and the limiting factor is instead the compression strength of the CLT-plate. This means that the CLT can be used more efficiently. Calculations show that it is possible to build up to 8 storeys higher with this solution compared to what is possible with the reference wall. With CLT increases the energy losses through the wall, i.e. increased U-value, since studs with insulation in between is partially replaced with CLT that has worse thermal conductivity. According to the calculations, the U-value is 20 – 40 % higher (depending on the wall type) compared to the reference wall. The increase in U-value can be limited to 0.4 – 14 % by adding an extra layer with 45 mm insulation on the inside of the CLT-plate. The cost for the wall types strengthened with CLT is also higher compared to the estimated cost for the reference wall. The main reason for this is increased cost of materials since the studs with insulation in between is partially replaced with the more expensive CLT, which is an engineered wood product. The increase in cost is estimated to roughly 40 – 50 % of the cost for the reference wall.
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APPLICERING AV INDUSTRIALISERADE METODER VID ETT TRADITIONELLT BYGGFÖRETAG : EN FALLSTUDIE / APPLICATION OF INDUSTRIALISED METHODS AT A TRADITIONAL CONSTRUCTION COMPANY : A CASE STUDY

Eriksson, Oscar January 2021 (has links)
The construction sector in Sweden released 21% of the country’s CO2-e emissions in. With aggressive climate and pollution goals these emissions cannot be allowed to increase. There is therefore a need for more efficient construction methods and techniques in the Swedish construction sector. The construction sector is today split up between industrial construction and traditional construction. Industrial construction handles the construction process with a strong emphasis on the process and allocates all its efforts toward streamlining the process and removing wasteful steps and elements. Traditional construction places more focus on the individual project. It has one major advantage, which is its exceptional ability to adapt the specific project according to the wishes and demands of the customer and the project’s other unique circumstances.   The IHB-model is the theory of industrial construction used in this study. This study seeks to find out which parts or mindsets from the IHB-model that can be applied to a traditional construction company, OF Bygg in Umeå, to increase its efficiency. This is done by studying the current use of industrial methods by OF Bygg, their views of industrial construction and comparing this to the IHB-model and looking at what parts can be applied to OF Bygg without fundamental shakeups in the company’s structure. The study of OF Bygg is mainly done through interviews with respondents from the company.    During the interviews, a sense of general positivity towards industrial construction was given off by the respondents. It also became apparent that OF Bygg was partially industrialised in some areas, but that there remains big possibilities for improvement.   Off-site manufacturing is used today in the shape of “field factories” and supply deals with industrial suppliers. Both of these are great industrialised methods and should be expanded upon whenever possible. Developed technical systems are used in most projects during certain stages. Efforts should be put into using these more extensively. ICT-tools are also used in most of OF Bygg’s areas but vertically integrating these tools further should be explored. Long term relations between OF Bygg and other market participants are rare since they’re considered detrimental to the health of the local market. Supply chain management is being handled through deals with logistics companies. OF Bygg could become their own logistics company with a centralised material warehouse to ease the logistics and enable use of JIT. Planning and control of the process is mostly handled through general project schedules. The Last Planner system alongside stricter routines is suggested. Customer focus is currently unnecessary for OF Bygg to bother with due to restrictions in the local market. Performance measurement and re-use of experience often get under prioritized often due to lack of time. The transfer of responsibility from the project or site management to a role specified to handle performance measurement and re-use of experience is encouraged.

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