A execução de obra de qualquer porte pode ocasionar o surgimento de danos à vizinhança. Tendo em ... more A execução de obra de qualquer porte pode ocasionar o surgimento de danos à vizinhança. Tendo em vista que, de acordo com o artigo 927 do Código Civil Brasileiro, quem ocasiona um dano a outrem é obrigado a repará-lo, a vistoria cautelar de vizinhança possui grande importância. É objetivo deste artigo verificar a existência de referências normativas que abordam esse tema. Foram apresentadas normas da Associação Brasileira de Normas Técnicas (ABNT) e do Instituto Brasileiro de Avaliações e Perícias de Engenharia de São Paulo (IBAPE-SP) e de Minas Gerais (IBAPE-MG). Verificou-se que não há norma específica sobre esse assunto na ABNT e que é pouco abordado nas normas existentes. Percebeu-se também que as normas do IBAPE-SP e IBAPE-MG buscam preencher a lacuna existente nas normas da ABNT com relação ao detalhamento desse serviço e oferecem diretrizes importantes para a melhoria da qualidade do laudo elaborado. Espera-se contribuir para o desenvolvimento bibliográfico e na elaboração de...
Fibers can increase the ductility of geopolymer materials, acting as reinforcements to improve me... more Fibers can increase the ductility of geopolymer materials, acting as reinforcements to improve mechanical properties. These improvements depend on fiber content and quantity. This study evaluates the impacts of different percentages of glass fiber on a GBFS (ground blast furnace slag) geopolymer matrix. The glass fibers were used on the critical length of 20 mm, obtained by pull-out test in previous studies. Percentages of 0.25%, 0.50%, 0.75%, and 1.00% of glass fiber in mass were tested in fresh state, by flow measurement, and in hardened state, by variation of shrinkage, water porosity and response of composites under flexural and compressive load conditions at 7, 14, 28, and 90 days. The mixture resulted in a high porosity geopolymer paste. In addition, an analysis of variance (ANOVA) was performed to evaluate the statistical significance of fibers in compressive strength. The results show that increasing percentages glass fibers, until 0.75%, enhances mechanical properties. Percentage of 1.00% started to show accumulation of branch of multifilament fibers which contribute to higher drying shrinkage. The ANOVA test showed that the percentage of fibers can influence the compressive strength. With the results, the optimum percentage of fibers for his composite mixture was found at 0.75%.
Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications
This work seeks to improve the understanding of the durability of pure slag-based geopolymer comp... more This work seeks to improve the understanding of the durability of pure slag-based geopolymer composites containing glass fibers. Degradation by attack of saline mist, simulated by the salt-spray essay, was carried out for a period of 30 days. The test simulates the conditions found in the sea and nearby environments. The chamber works at relative humidity ∼97%, by nebulizing sodium chloride solutions with a concentration of 5% at 35 + 2 °C, solution pH between 6.5 and 7.2. After the cycle, the loss of mass and the compressive strength of the specimens were measured. The efflorescence formation in slag-based geopolymers is also assessed in this study to provide a better understanding of the effect of the synthesis parameters. It is noted that physical and chemical properties of geopolymers, and environmental exposure conditions can affect the rate of efflorescence formation. Besides the control set group, two different solutions to prevent efflorescence were tested, MgO and an efflor...
Abstract The reinforcement efficiency on a composite depends on the effective transfer of the str... more Abstract The reinforcement efficiency on a composite depends on the effective transfer of the stress between matrix and fiber. This work presents an experimental and comparative study of fiber-matrix bond strength for fiber-matrix interface between glass fibers and carbon fibers added to the slag-based geopolymer matrix. This analysis was performed by pull-out test. A total of 18 tests have been conducted, three for each type of fiber at each embedded length of 10 mm, 20 mm and 30 mm. The critical embedded length and the maximum interfacial shear (bond) strength were analyzed, and SEM observations were carried out for the cross-section of each fiber to measure diameter and observe the interface. It was found that the greatest efficiency was obtained by reinforcing with the glass fibers, incorporated at 20 mm in the slag-based matrix.
As Giannopoulou and Panias [1] explained, the main means of production of the geopolymers is thro... more As Giannopoulou and Panias [1] explained, the main means of production of the geopolymers is through a reaction composed of a solid phase, called precursor, and a liquid phase, known as activator. The precursor is characterized by reactive aluminosilicate materials, frequently used metakaolin and fly ash. The activator is composed of an alkaline solution, usually sodium hydroxide (NaOH) or potassium hydroxide (KOH). In general, regardless of the aluminosilicate material used, the macroscopic characteristics of the product will be similar. However, there will be variation-often significant-in the microstructure, affecting also the chemical, mechanical and thermal properties. This variation will depend on which material was used and what were its molar ratios [2].
Concrete is a major construction material that produces high levels of carbon dioxide in its manu... more Concrete is a major construction material that produces high levels of carbon dioxide in its manufacturing process. Hence the construction sector is responsible for relevant environmental impacts. This justifies the need to find materials as green and ecological alternatives to common Portland cement. Geopolymers represent the most promising alternative due to its proven durability, mechanical and thermal properties. This study investigates the effects of solid-to-liquid and alkali activator ratios on the synthesis of slag-based pure geopolymer and their relation to the geopolymerization process. Two activating solutions were used: a) a mixture of sodium hydroxide, sodium silicate, and water; and b) a mixture of potassium hydroxide solution, potassium silicate, and water. As precursor material, ground blast furnace slag was used. Precursors and activators were mixed with solid-to-liquid ratios in range of 1.5 to 2.2. In the first stage of the study, the mechanical properties were ev...
XV International Conference on Durability of Building Materials and Components. eBook of Proceedings
The so-called works of special arts, are constructions of high complexities that allow the advanc... more The so-called works of special arts, are constructions of high complexities that allow the advancement of widening gaps and overcoming obstacles previously unthinkable. With the increase in magnitude of these structures, in addition to greater investments, the maintenance of these structures becomes an increasingly important factor for engineering. Among the elements of bridge structures, the support devices are components with important structural functions, being essential for their proper functioning and especially the durability of the entire structure. This paper aims to evaluate the pathological manifestations in support devices so, according to inspections performed and the diagnosis of causes, define their best practices and treatments for the maintenance and mitigation of the pathologies found. In the practical study the following steps were performed: survey and selection of the structures currently under maintenance of MetrôRio; selection of criteria for the evaluation of pathologies; carrying out inspections; comparative analysis between the viaducts to determine the priority order for negotiations; and definition of conduct. The results obtained were the result of evaluation of the field analysis, diagnosis and comparison with tests performed in support devices. Having as input the tests in the support devices, the best treatments and suggestions to avoid new pathologies were proposed.
A competitividade do mercado atual da construção civil criou a necessidade de reduzirprazos e cus... more A competitividade do mercado atual da construção civil criou a necessidade de reduzirprazos e custos na execução das obras. Por causa dessa necessidade e a grandedificuldade para atendê-la, devido à falta de uma cultura de planejamento, as empresasde construção estão investindo cada vez mais tempo e dinheiro na implantação desistemas de gestão, buscando atingir um planejamento físico-financeiro mais eficiente.O presente trabalho abordará a relação entre planejamento e custo dentro de uma obra.Serão levantados conceitos e técnicas de ambos. Por meio de um estudo de caso, serãoanalisados o orçamento e o cronograma de um empreendimento, e serão mostradosos desvios em relação ao planejamento inicial, os motivos dos desvios encontrados,os impactos causados e a importância de um planejamento mais eficiente para quemelhores resultados sejam alcançados.
O projeto visa estudar o modelo de certificação "Procel Edifica" e criar uma metodologia para a a... more O projeto visa estudar o modelo de certificação "Procel Edifica" e criar uma metodologia para a aplicação da certificação através da criação de uma lista de verificação com os procedimentos necessários. A rotulagem dos edifícios pela certificação Procel é feita avaliando a fachada do edifício, o sistema de iluminação e o sistema de ar condicionado. Cada sistema recebe o correspondente rótulo de eficiência energética, que combinado corresponde a uma certificação de classificação de eficiência para o edifício. O objetivo deste estudo é analisar, através de um estudo de caso, a metodologia proposta pela Procel através da aplicação do
Growing concern about environmental degradation has expanded the search for new technologies that... more Growing concern about environmental degradation has expanded the search for new technologies that could ensure sustainable development. In civil construction, new materials have emerged as alternatives to reduce the impact of the activity on the environment, one of them is the geopolymer. This material, which can be characterized as a stable and synthesized composite of aluminosilicate materials, has emerged as a potential substitute for Portland cement because it presents similar characteristics of initial strength and good mechanical performance, but without the high emission of carbon dioxide (CO2) to obtaining it. This work brings a bibliographic analysis on geopolymer, it is intended to disseminate knowledge as of the state of the art on geopolymer as cement substitute.
Between 2005 and 2015, the Brazilian real estate market experienced strong growth, driven by the ... more Between 2005 and 2015, the Brazilian real estate market experienced strong growth, driven by the stable scenario of the Brazilian economy and policies to encourage real estate credit. With this demand, the companies of the sector sought to be more competitive in the market. One of the measures adopted is the search for more efficient executive processes. While the traditional manual methodology for underlayment predominates in the country's construction sites, a self-levelling underlayment presents a tendency towards mechanization of executive construction procedures. This paper aims to present a case study of a residential construction in Rio de Janeiro, which used self-levelling underlayment technology. Comparisons regarding cost and productivity of both methodologies were made to evaluate the viability of the self-levelling underlayment in future construction sites. Data obtained from other constructions were used to estimate the productivity and cost of the traditional underlayment levelling. The results demonstrate that the use of self-levelling underlayment has potential to be widespread and used in the constructions in Brazil.
The lack of proper maintenance in buildings is responsible for various anomalies, which can cause... more The lack of proper maintenance in buildings is responsible for various anomalies, which can cause property and personal damage. The objective of this study is to analyze the maintenance management of the administration building at the Technological Park UFRJ/Brazil, trying to emphasize the relation between maintenance and good performance of the building and to demonstrate the need to develop a consistent maintenance system to achieve an efficient maintenance management. The study allowed to present strategies and possibilities of interventions, in addition to proposing the essential aspects for the development of a structured maintenance system. After reviewing the issue of building maintenance under the various perspectives presented, the importance of planning a preventive building maintenance, according to standards, to achieve the level of performance expected for the building, besides being essential the search for tools and methods that can increase the efficiency of management can be concluded. It is also pertinent to conclude that prevention is the most effective solution against the depreciation factors that affect a building, being the most economical viable, and ensuring other benefits for the building and its users, such as security, property valuation and attendance to the warranty period.
Cement industry has a great contribution to CO2 emissions in the world. In order to reduce the le... more Cement industry has a great contribution to CO2 emissions in the world. In order to reduce the levels of CO2 emissions and the consequences of global warming, some researches have been developed aiming to reduce the cement volume produced through mineral mixtures. Sugarcane bagasse ash (SCBA) represents an important environmental liability of the alcohol industry in the northern state of Rio de Janeiro and its use as a partial replacement of Portland cement in concrete has shown great potential for use. This paper aims to analyze, through experimental procedures, the consistency and mechanic strength on concrete with low environmental impact, made from sugarcane bagasse ash, in substitution levels of 20% and 40%. The methodology of the experimental program, included the steps of characterizing the materials; definition of the reference concrete; molding and dosing of the reference concrete and concrete with SCBA; mechanical tests to evaluate the resistance in the reference test bodi...
A execução de obra de qualquer porte pode ocasionar o surgimento de danos à vizinhança. Tendo em ... more A execução de obra de qualquer porte pode ocasionar o surgimento de danos à vizinhança. Tendo em vista que, de acordo com o artigo 927 do Código Civil Brasileiro, quem ocasiona um dano a outrem é obrigado a repará-lo, a vistoria cautelar de vizinhança possui grande importância. É objetivo deste artigo verificar a existência de referências normativas que abordam esse tema. Foram apresentadas normas da Associação Brasileira de Normas Técnicas (ABNT) e do Instituto Brasileiro de Avaliações e Perícias de Engenharia de São Paulo (IBAPE-SP) e de Minas Gerais (IBAPE-MG). Verificou-se que não há norma específica sobre esse assunto na ABNT e que é pouco abordado nas normas existentes. Percebeu-se também que as normas do IBAPE-SP e IBAPE-MG buscam preencher a lacuna existente nas normas da ABNT com relação ao detalhamento desse serviço e oferecem diretrizes importantes para a melhoria da qualidade do laudo elaborado. Espera-se contribuir para o desenvolvimento bibliográfico e na elaboração de...
Fibers can increase the ductility of geopolymer materials, acting as reinforcements to improve me... more Fibers can increase the ductility of geopolymer materials, acting as reinforcements to improve mechanical properties. These improvements depend on fiber content and quantity. This study evaluates the impacts of different percentages of glass fiber on a GBFS (ground blast furnace slag) geopolymer matrix. The glass fibers were used on the critical length of 20 mm, obtained by pull-out test in previous studies. Percentages of 0.25%, 0.50%, 0.75%, and 1.00% of glass fiber in mass were tested in fresh state, by flow measurement, and in hardened state, by variation of shrinkage, water porosity and response of composites under flexural and compressive load conditions at 7, 14, 28, and 90 days. The mixture resulted in a high porosity geopolymer paste. In addition, an analysis of variance (ANOVA) was performed to evaluate the statistical significance of fibers in compressive strength. The results show that increasing percentages glass fibers, until 0.75%, enhances mechanical properties. Percentage of 1.00% started to show accumulation of branch of multifilament fibers which contribute to higher drying shrinkage. The ANOVA test showed that the percentage of fibers can influence the compressive strength. With the results, the optimum percentage of fibers for his composite mixture was found at 0.75%.
Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications
This work seeks to improve the understanding of the durability of pure slag-based geopolymer comp... more This work seeks to improve the understanding of the durability of pure slag-based geopolymer composites containing glass fibers. Degradation by attack of saline mist, simulated by the salt-spray essay, was carried out for a period of 30 days. The test simulates the conditions found in the sea and nearby environments. The chamber works at relative humidity ∼97%, by nebulizing sodium chloride solutions with a concentration of 5% at 35 + 2 °C, solution pH between 6.5 and 7.2. After the cycle, the loss of mass and the compressive strength of the specimens were measured. The efflorescence formation in slag-based geopolymers is also assessed in this study to provide a better understanding of the effect of the synthesis parameters. It is noted that physical and chemical properties of geopolymers, and environmental exposure conditions can affect the rate of efflorescence formation. Besides the control set group, two different solutions to prevent efflorescence were tested, MgO and an efflor...
Abstract The reinforcement efficiency on a composite depends on the effective transfer of the str... more Abstract The reinforcement efficiency on a composite depends on the effective transfer of the stress between matrix and fiber. This work presents an experimental and comparative study of fiber-matrix bond strength for fiber-matrix interface between glass fibers and carbon fibers added to the slag-based geopolymer matrix. This analysis was performed by pull-out test. A total of 18 tests have been conducted, three for each type of fiber at each embedded length of 10 mm, 20 mm and 30 mm. The critical embedded length and the maximum interfacial shear (bond) strength were analyzed, and SEM observations were carried out for the cross-section of each fiber to measure diameter and observe the interface. It was found that the greatest efficiency was obtained by reinforcing with the glass fibers, incorporated at 20 mm in the slag-based matrix.
As Giannopoulou and Panias [1] explained, the main means of production of the geopolymers is thro... more As Giannopoulou and Panias [1] explained, the main means of production of the geopolymers is through a reaction composed of a solid phase, called precursor, and a liquid phase, known as activator. The precursor is characterized by reactive aluminosilicate materials, frequently used metakaolin and fly ash. The activator is composed of an alkaline solution, usually sodium hydroxide (NaOH) or potassium hydroxide (KOH). In general, regardless of the aluminosilicate material used, the macroscopic characteristics of the product will be similar. However, there will be variation-often significant-in the microstructure, affecting also the chemical, mechanical and thermal properties. This variation will depend on which material was used and what were its molar ratios [2].
Concrete is a major construction material that produces high levels of carbon dioxide in its manu... more Concrete is a major construction material that produces high levels of carbon dioxide in its manufacturing process. Hence the construction sector is responsible for relevant environmental impacts. This justifies the need to find materials as green and ecological alternatives to common Portland cement. Geopolymers represent the most promising alternative due to its proven durability, mechanical and thermal properties. This study investigates the effects of solid-to-liquid and alkali activator ratios on the synthesis of slag-based pure geopolymer and their relation to the geopolymerization process. Two activating solutions were used: a) a mixture of sodium hydroxide, sodium silicate, and water; and b) a mixture of potassium hydroxide solution, potassium silicate, and water. As precursor material, ground blast furnace slag was used. Precursors and activators were mixed with solid-to-liquid ratios in range of 1.5 to 2.2. In the first stage of the study, the mechanical properties were ev...
XV International Conference on Durability of Building Materials and Components. eBook of Proceedings
The so-called works of special arts, are constructions of high complexities that allow the advanc... more The so-called works of special arts, are constructions of high complexities that allow the advancement of widening gaps and overcoming obstacles previously unthinkable. With the increase in magnitude of these structures, in addition to greater investments, the maintenance of these structures becomes an increasingly important factor for engineering. Among the elements of bridge structures, the support devices are components with important structural functions, being essential for their proper functioning and especially the durability of the entire structure. This paper aims to evaluate the pathological manifestations in support devices so, according to inspections performed and the diagnosis of causes, define their best practices and treatments for the maintenance and mitigation of the pathologies found. In the practical study the following steps were performed: survey and selection of the structures currently under maintenance of MetrôRio; selection of criteria for the evaluation of pathologies; carrying out inspections; comparative analysis between the viaducts to determine the priority order for negotiations; and definition of conduct. The results obtained were the result of evaluation of the field analysis, diagnosis and comparison with tests performed in support devices. Having as input the tests in the support devices, the best treatments and suggestions to avoid new pathologies were proposed.
A competitividade do mercado atual da construção civil criou a necessidade de reduzirprazos e cus... more A competitividade do mercado atual da construção civil criou a necessidade de reduzirprazos e custos na execução das obras. Por causa dessa necessidade e a grandedificuldade para atendê-la, devido à falta de uma cultura de planejamento, as empresasde construção estão investindo cada vez mais tempo e dinheiro na implantação desistemas de gestão, buscando atingir um planejamento físico-financeiro mais eficiente.O presente trabalho abordará a relação entre planejamento e custo dentro de uma obra.Serão levantados conceitos e técnicas de ambos. Por meio de um estudo de caso, serãoanalisados o orçamento e o cronograma de um empreendimento, e serão mostradosos desvios em relação ao planejamento inicial, os motivos dos desvios encontrados,os impactos causados e a importância de um planejamento mais eficiente para quemelhores resultados sejam alcançados.
O projeto visa estudar o modelo de certificação "Procel Edifica" e criar uma metodologia para a a... more O projeto visa estudar o modelo de certificação "Procel Edifica" e criar uma metodologia para a aplicação da certificação através da criação de uma lista de verificação com os procedimentos necessários. A rotulagem dos edifícios pela certificação Procel é feita avaliando a fachada do edifício, o sistema de iluminação e o sistema de ar condicionado. Cada sistema recebe o correspondente rótulo de eficiência energética, que combinado corresponde a uma certificação de classificação de eficiência para o edifício. O objetivo deste estudo é analisar, através de um estudo de caso, a metodologia proposta pela Procel através da aplicação do
Growing concern about environmental degradation has expanded the search for new technologies that... more Growing concern about environmental degradation has expanded the search for new technologies that could ensure sustainable development. In civil construction, new materials have emerged as alternatives to reduce the impact of the activity on the environment, one of them is the geopolymer. This material, which can be characterized as a stable and synthesized composite of aluminosilicate materials, has emerged as a potential substitute for Portland cement because it presents similar characteristics of initial strength and good mechanical performance, but without the high emission of carbon dioxide (CO2) to obtaining it. This work brings a bibliographic analysis on geopolymer, it is intended to disseminate knowledge as of the state of the art on geopolymer as cement substitute.
Between 2005 and 2015, the Brazilian real estate market experienced strong growth, driven by the ... more Between 2005 and 2015, the Brazilian real estate market experienced strong growth, driven by the stable scenario of the Brazilian economy and policies to encourage real estate credit. With this demand, the companies of the sector sought to be more competitive in the market. One of the measures adopted is the search for more efficient executive processes. While the traditional manual methodology for underlayment predominates in the country's construction sites, a self-levelling underlayment presents a tendency towards mechanization of executive construction procedures. This paper aims to present a case study of a residential construction in Rio de Janeiro, which used self-levelling underlayment technology. Comparisons regarding cost and productivity of both methodologies were made to evaluate the viability of the self-levelling underlayment in future construction sites. Data obtained from other constructions were used to estimate the productivity and cost of the traditional underlayment levelling. The results demonstrate that the use of self-levelling underlayment has potential to be widespread and used in the constructions in Brazil.
The lack of proper maintenance in buildings is responsible for various anomalies, which can cause... more The lack of proper maintenance in buildings is responsible for various anomalies, which can cause property and personal damage. The objective of this study is to analyze the maintenance management of the administration building at the Technological Park UFRJ/Brazil, trying to emphasize the relation between maintenance and good performance of the building and to demonstrate the need to develop a consistent maintenance system to achieve an efficient maintenance management. The study allowed to present strategies and possibilities of interventions, in addition to proposing the essential aspects for the development of a structured maintenance system. After reviewing the issue of building maintenance under the various perspectives presented, the importance of planning a preventive building maintenance, according to standards, to achieve the level of performance expected for the building, besides being essential the search for tools and methods that can increase the efficiency of management can be concluded. It is also pertinent to conclude that prevention is the most effective solution against the depreciation factors that affect a building, being the most economical viable, and ensuring other benefits for the building and its users, such as security, property valuation and attendance to the warranty period.
Cement industry has a great contribution to CO2 emissions in the world. In order to reduce the le... more Cement industry has a great contribution to CO2 emissions in the world. In order to reduce the levels of CO2 emissions and the consequences of global warming, some researches have been developed aiming to reduce the cement volume produced through mineral mixtures. Sugarcane bagasse ash (SCBA) represents an important environmental liability of the alcohol industry in the northern state of Rio de Janeiro and its use as a partial replacement of Portland cement in concrete has shown great potential for use. This paper aims to analyze, through experimental procedures, the consistency and mechanic strength on concrete with low environmental impact, made from sugarcane bagasse ash, in substitution levels of 20% and 40%. The methodology of the experimental program, included the steps of characterizing the materials; definition of the reference concrete; molding and dosing of the reference concrete and concrete with SCBA; mechanical tests to evaluate the resistance in the reference test bodi...
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