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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.
111

Concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais / Lightweight concrete with innovative calcined clay lightweight aggregates with agro-industrial by-products

Santis, Bruno Carlos de 18 November 2016 (has links)
Este trabalho tem por objetivo o estudo de concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais. A argila utilizada na pesquisa foi caracterizada por meio das técnicas de limites de liquidez (LL) e plasticidade (LP), análise granulométrica, análise química e difração de raios X (DRX). Foram confeccionados corpos de prova de argila vermelha calcinada com incorporações de serragem de madeira, cinza do bagaço da cana-de-açúcar e silicato de sódio. Os corpos de prova de argila vermelha calcinada, queimados à temperatura de 900 °C, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Após a caracterização dos corpos de prova de argila vermelha calcinada, foram produzidos dois tipos de agregados, sendo o primeiro composto por 57% de argila e 43% de cinza do bagaço de cana-de-açúcar, conformados com água e silicato de sódio (proporção 1:1), e o segundo composto por 70% de argila e 30% de serragem de madeira. Os corpos de prova de concreto leve foram caracterizados pelos ensaios de slump, massa específica fresca, resistência à compressão, módulo de deformação, retração por secagem, absorção de água, índice de vazios e massa específica aparente e condutividade térmica. Os resultados desta pesquisa indicam a viabilidade da produção de agregados leves de argila vermelha calcinada com incorporações de subprodutos agroindustriais para utilização em concretos, uma vez que, mesmo com grande quantidade de utilização de subprodutos agroindustriais na produção dos agregados leves, os concretos produzidos com esses agregados apresentaram características similares aos concretos produzidos com agregados comerciais, apresentando um ganho econômico e energético significativo. / This paper aims to study lightweight concrete with innovative calcined clay lightweight aggregates made with agro-industrial by-products. The clay used in this research was characterized by techniques of liquid and plastic limits, particle size analysis, chemical analysis and X-ray diffraction (XRD). Calcined clay specimens were made with incorporations of wood sawdust, sugar cane ash and sodium silicate. These specimens, burned at a temperature of 900°C, were characterized by evaluating of linear shrinkage, water absorption, apparent porosity, specific mass, moisture expansion and compressive strength. After characterization of calcined clay specimens, two types of calcined clay lightweight aggregates with agro-industrial by-products were produced, wherein the first made with 57% of clay and 43% of sugar cane ash, mixed with water and sodium silicate (proportion 1:1) and the second made with 70% clay and 30% wood sawdust, mixed with water and burned at 900 °C. Specimens of lightweight concrete were characterized by slump test, fresh specific mass, compressive strength, modulus of elasticity, water absorption, voids and bulk density and thermal conductivity. Results of this research indicates the viability to produce calcined clay lightweight aggregates made with agro-industrial by-products to use in concrete, even using large amount of agro-industrial by-products, once concretes made with lightweight aggregates with agro-industrial by-products presented similar characteristics than those made with commercial aggregates, presenting significant energetic gain.
112

Influência do teor de ar incorporado no desempenho de concretos com diferentes teores de agregados / The influence of air entrained content in concrete performance with different aggregate contents

Barbar, Joseph Salem 11 November 2016 (has links)
A utilização de aditivos incorporadores de ar em concretos é uma prática comum na construção civil e sua aplicação influencia significativamente diversas propriedades do concreto no estado fresco e endurecido. O objetivo deste estudo foi avaliar a influência do teor de ar incorporado, por meio de aditivo, no desempenho de concretos com diferentes teores de agregados. O programa experimental incluiu avaliação da eficiência de aditivos na incorporação de ar em pastas de cimento, análise microestrutural e ensaios para determinação de propriedades físicas, mecânicas e de durabilidade de concretos com diferentes teores de ar e agregados. No estado fresco, foram realizados ensaios para determinação do teor de ar, massa específica e abatimento. No estado endurecido foram realizados ensaios de massa específica, absorção, resistência à compressão, módulo de elasticidade, velocidade de propagação da onda ultrassônica, carbonatação acelerada e condutividade térmica. Utilizando Microtomografia Computadorizada de Raios-X (Micro-CT) foram dimensionados e quantificados os poros presentes nas amostras dos concretos, bem como determinadas suas porosidades. Os concretos com ar incorporado apresentaram redução na resistência mecânica. Os concretos com menores teores de agregados apresentaram menor resistência mecânica, menor velocidade da frente de carbonatação e menor condutividade térmica. De acordo com os resultados obtidos, pode-se concluir que o aditivo a base de resinas sintéticas foi mais eficiente na incorporação de ar; maiores teores de ar implicam em variabilidade nos resultados de ensaios de resistência à compressão e módulo de elasticidade; os concretos com maiores teores de agregados apresentaram maior velocidade da frente de carbonatação, para mesmos teores de ar incorporado; a condutividade térmica é inversamente proporcional ao teor de ar incorporado no concreto, e quanto menor o teor de agregados, menor a condutividade térmica; o aumento do teor de ar no concreto promove aumento no diâmetro equivalente dos poros e redução da incidência de poros esféricos. / The use of entraining air additives in concrete is a common practice in construction and its application influences several concrete properties in the fresh and hardened state. The aim of this study was evaluate the influence of air entrained content, by additive, in concrete performance with different aggregate contents. The experimental program included the evaluation of additives effectiveness of air entrainment in cement pastes, microstructural analysis and the concretes physical and mechanical properties and durability, with different levels of entrained air and aggregates. Tests were performed in fresh to determine the air content, density and slump. In hardened concrete, density, absorption, compressive strength, elastic modulus, ultrasonic pulse velocity, accelerated carbonation and thermal conductivity tests were performed. By computed X-ray microtomography, the pores present in the concrete samples were sized and quantified and determined the concretes porosities. The air entrained concrete presented decrease in mechanical strength. Concretes with lower aggregate levels presented lower mechanical strength, carbonation speed and thermal conductivity. According to the results, it can be concluded that the synthetic resins base additive was more efficient in air entrainment; larger air content implies variability in the results of the compressive strength and elastic modulus tests; concrete with higher aggregate levels presented higher carbonation speed, for the same entrained air content; thermal conductivity is inversely proportional to the air entrained content in concrete, and as lower was the aggregate content, lower was the thermal conductivity; the increase of air content in concrete promotes increase in the pores diameter and reduction of the incidence of spherical pores.
113

Concreto celular polim?rico: influ?ncia na adi??o de res?duo de poli?ster insaturado termofixo

Melo, Guilherme F?bio de 23 March 2009 (has links)
Made available in DSpace on 2014-12-17T14:07:00Z (GMT). No. of bitstreams: 1 GuilhermeFM.pdf: 1361832 bytes, checksum: 90befe7961c07f2510ca8f988b71da6b (MD5) Previous issue date: 2009-03-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This work addresses the production of lightweight concrete building elements, such as plates, prefabricated slabs for pre-molded and panels of fencing, presenting a singular concrete: the Lightweight Concrete, with special properties such low density and good strength, by means of the joint use of industrial waste of thermosetting unsaturated polyesters and biodegradable foaming agent, named Polymeric Lightweight Concrete. This study covered various features of the materials used in the composition of the Polymeric Lightweight Concrete, using a planning of factorial design 23, aiming at studying of the strength, production, dosage processes, characterization of mechanical properties and microstructural analysis of the transition zone between the light artificial aggregate and the matrix of cement. The results of the mechanical strength tests were analyzed using a computational statistics tool (Statistica software) to understand the behavior and obtain the ideal quantity of each material used in the formula of the Polymeric Lightweight Concrete. The definition of the ideal formula has the purpose of obtaining a material with the lowest possible dry density and resistance to compression in accordance with NBR 12.646/92 (≥ 2.5 MPa after 28 days). In the microstructural characterization by scanning electron microscopy it was observed an influence of the materials in the process of cement hydration, showing good interaction between the wrinkled face of the residue of unsaturated polyesters thermosetting and putty and, consequently, the final strength. The attaining of an ideal formula, given the Brazilian standards, the experimental results obtained in the characterization and comparison of these results with conventional materials, confirmed that the developed Polymeric Lightweight Concrete is suitable for the production of building elements that are advantageous for construction / Neste trabalho ? abordada a aplica??o da tecnologia dos concretos leves ? produ??o de elementos construtivos, tais como placas pr?-fabricadas para lajes pr?-moldadas, pain?is de veda??o e pe?as pr?-moldadas, e ao desenvolvimento de um concreto celular com propriedades especiais de baixa densidade e boa resist?ncia mec?nica, em fun??o da utiliza??o conjunta de res?duo industrial de poli?ster insaturado termofixo (PIT) e espuma biodegrad?vel incorporadora de ar, denominado de Concreto Celular Polim?rico (CCP) . O estudo abrangeu diferentes tra?os dos materiais empregados na composi??o do CCP, sendo utilizado um planejamento fatorial 23, para an?lises dos processos de dosagem e produ??o, caracteriza??o das propriedades mec?nicas, bem como an?lises microestruturais da zona de transi??o entre o agregado artificial leve (PIT) e a matriz de cimento. Os resultados dos testes de resist?ncia mec?nica foram analisados utilizando-se uma ferramenta computacional de estat?stica (Statistica Software) para compreens?o do comportamento e obten??o da concentra??o ideal de cada material utilizado na formula??o do CCP. A defini??o da f?rmula ideal teve como finalidade a obten??o de um material com a menor densidade a seco poss?vel e resist?ncia ? compress?o que atendesse ? norma NBR 12.646/92 (≥ 2,5 MPa aos 28 dias). Na caracteriza??o microestrutural por microscopia eletr?nica de varredura, observou-se a influ?ncia dos materiais no processo de hidrata??o do cimento, onde constatou-se boa intera??o entre o res?duo de PIT, cuja face ? enrugada, e a pasta de cimento. A obten??o da formula??o de um novo material que atende ? norma brasileira, os resultados experimentais obtidos nas caracteriza??es e compara??o desses resultados com materiais convencionais, comprovaram que o Concreto Celular Polim?rico desenvolvido ? adequado ? produ??o de elementos construtivos que apresentam vantagens quando aplicados ? constru??o civil
114

Edifícios com lajes maciças e paredes portantes pré-moldadas de concreto leve com pérolas de EPS / Buildings with solid slabs and load bearing precast walls of lightweight concrete with EPS beads

Diego de Vasconcelos Gonçalves Ferreira 28 May 2013 (has links)
Atualmente, muitas empresas de construção civil não acompanham o avanço tecnológico, preferindo utilizar sistemas convencionais em vez de investir em novas soluções. Além disso, há sérios problemas com mão de obra, que estão cada vez mais presentes na sociedade. Este trabalho apresenta o projeto de um edifício com elementos pré-moldados de Concreto Leve com pérolas de EPS, considerando lajes prontas maciças e paredes portantes, executadas com esse tipo de material. A princípio, foram considerados os estados limites últimos e de serviço para os elementos da estrutura, utilizando os modelos clássicos de análise estrutural. Para modelagem do edifício, foi utilizado o programa comercial SAP2000. Quanto aos procedimentos para dimensionamento das peças, foram preparadas planilhas do Excel, enquanto o detalhamento foi realizado por meio do AutoCAD. Definido o projeto estrutural, foram considerados aspectos construtivos na fábrica e na obra, levando em conta os custos de produção e de transporte, além de apresentar as vantagens que esse sistema construtivo pode proporcionar. Esses custos foram considerados para as lajes prontas maciças e para as paredes pré-moldadas. Mesmo levando em conta apenas os custos de produção e de transporte, o Concreto Leve com EPS foi comparado com o Concreto Autoadensável, o que permitiu visualizar as vantagens do primeiro, quando for considerado o custo global do empreendimento. / Currently, many construction companies do not follow the technological advances, preferring to use conventional systems rather than investing in new solutions. Moreover, there are serious problems with manpower, which are increasingly present in society. This work presents the design of a building with precast elements of lightweight concrete with EPS beads, considering solid slabs ready to use and load bearing walls, made with this type of material. As a rule, the ultimate limit states and serviceability were considered for the elements of the structure, using classical models of structural analysis. For modelling the building, the commercial software SAP2000 was used. Regarding the procedures for dimensioning of the pieces, Excel spreadsheets were prepared, while the detailing was carried out by means of the AutoCAD. Defined structural design, construction aspects were considered in the factory and in the work, taking into account costs of production and transportation, besides presenting the advantages that this constructive system can provide. These costs were considered for the solid slabs ready to use and for the precast walls. Even taking into account only the cost of production and transportation, the Lightweight Concrete with EPS was compared with Self-compacting Concrete, allowing visualize the advantages of the former when considering the overall cost of the project.
115

Concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais / Lightweight concrete with innovative calcined clay lightweight aggregates with agro-industrial by-products

Bruno Carlos de Santis 18 November 2016 (has links)
Este trabalho tem por objetivo o estudo de concretos leves com agregados inovadores de argila vermelha calcinada e subprodutos agroindustriais. A argila utilizada na pesquisa foi caracterizada por meio das técnicas de limites de liquidez (LL) e plasticidade (LP), análise granulométrica, análise química e difração de raios X (DRX). Foram confeccionados corpos de prova de argila vermelha calcinada com incorporações de serragem de madeira, cinza do bagaço da cana-de-açúcar e silicato de sódio. Os corpos de prova de argila vermelha calcinada, queimados à temperatura de 900 °C, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Após a caracterização dos corpos de prova de argila vermelha calcinada, foram produzidos dois tipos de agregados, sendo o primeiro composto por 57% de argila e 43% de cinza do bagaço de cana-de-açúcar, conformados com água e silicato de sódio (proporção 1:1), e o segundo composto por 70% de argila e 30% de serragem de madeira. Os corpos de prova de concreto leve foram caracterizados pelos ensaios de slump, massa específica fresca, resistência à compressão, módulo de deformação, retração por secagem, absorção de água, índice de vazios e massa específica aparente e condutividade térmica. Os resultados desta pesquisa indicam a viabilidade da produção de agregados leves de argila vermelha calcinada com incorporações de subprodutos agroindustriais para utilização em concretos, uma vez que, mesmo com grande quantidade de utilização de subprodutos agroindustriais na produção dos agregados leves, os concretos produzidos com esses agregados apresentaram características similares aos concretos produzidos com agregados comerciais, apresentando um ganho econômico e energético significativo. / This paper aims to study lightweight concrete with innovative calcined clay lightweight aggregates made with agro-industrial by-products. The clay used in this research was characterized by techniques of liquid and plastic limits, particle size analysis, chemical analysis and X-ray diffraction (XRD). Calcined clay specimens were made with incorporations of wood sawdust, sugar cane ash and sodium silicate. These specimens, burned at a temperature of 900°C, were characterized by evaluating of linear shrinkage, water absorption, apparent porosity, specific mass, moisture expansion and compressive strength. After characterization of calcined clay specimens, two types of calcined clay lightweight aggregates with agro-industrial by-products were produced, wherein the first made with 57% of clay and 43% of sugar cane ash, mixed with water and sodium silicate (proportion 1:1) and the second made with 70% clay and 30% wood sawdust, mixed with water and burned at 900 °C. Specimens of lightweight concrete were characterized by slump test, fresh specific mass, compressive strength, modulus of elasticity, water absorption, voids and bulk density and thermal conductivity. Results of this research indicates the viability to produce calcined clay lightweight aggregates made with agro-industrial by-products to use in concrete, even using large amount of agro-industrial by-products, once concretes made with lightweight aggregates with agro-industrial by-products presented similar characteristics than those made with commercial aggregates, presenting significant energetic gain.
116

Influência do teor de ar incorporado no desempenho de concretos com diferentes teores de agregados / The influence of air entrained content in concrete performance with different aggregate contents

Joseph Salem Barbar 11 November 2016 (has links)
A utilização de aditivos incorporadores de ar em concretos é uma prática comum na construção civil e sua aplicação influencia significativamente diversas propriedades do concreto no estado fresco e endurecido. O objetivo deste estudo foi avaliar a influência do teor de ar incorporado, por meio de aditivo, no desempenho de concretos com diferentes teores de agregados. O programa experimental incluiu avaliação da eficiência de aditivos na incorporação de ar em pastas de cimento, análise microestrutural e ensaios para determinação de propriedades físicas, mecânicas e de durabilidade de concretos com diferentes teores de ar e agregados. No estado fresco, foram realizados ensaios para determinação do teor de ar, massa específica e abatimento. No estado endurecido foram realizados ensaios de massa específica, absorção, resistência à compressão, módulo de elasticidade, velocidade de propagação da onda ultrassônica, carbonatação acelerada e condutividade térmica. Utilizando Microtomografia Computadorizada de Raios-X (Micro-CT) foram dimensionados e quantificados os poros presentes nas amostras dos concretos, bem como determinadas suas porosidades. Os concretos com ar incorporado apresentaram redução na resistência mecânica. Os concretos com menores teores de agregados apresentaram menor resistência mecânica, menor velocidade da frente de carbonatação e menor condutividade térmica. De acordo com os resultados obtidos, pode-se concluir que o aditivo a base de resinas sintéticas foi mais eficiente na incorporação de ar; maiores teores de ar implicam em variabilidade nos resultados de ensaios de resistência à compressão e módulo de elasticidade; os concretos com maiores teores de agregados apresentaram maior velocidade da frente de carbonatação, para mesmos teores de ar incorporado; a condutividade térmica é inversamente proporcional ao teor de ar incorporado no concreto, e quanto menor o teor de agregados, menor a condutividade térmica; o aumento do teor de ar no concreto promove aumento no diâmetro equivalente dos poros e redução da incidência de poros esféricos. / The use of entraining air additives in concrete is a common practice in construction and its application influences several concrete properties in the fresh and hardened state. The aim of this study was evaluate the influence of air entrained content, by additive, in concrete performance with different aggregate contents. The experimental program included the evaluation of additives effectiveness of air entrainment in cement pastes, microstructural analysis and the concretes physical and mechanical properties and durability, with different levels of entrained air and aggregates. Tests were performed in fresh to determine the air content, density and slump. In hardened concrete, density, absorption, compressive strength, elastic modulus, ultrasonic pulse velocity, accelerated carbonation and thermal conductivity tests were performed. By computed X-ray microtomography, the pores present in the concrete samples were sized and quantified and determined the concretes porosities. The air entrained concrete presented decrease in mechanical strength. Concretes with lower aggregate levels presented lower mechanical strength, carbonation speed and thermal conductivity. According to the results, it can be concluded that the synthetic resins base additive was more efficient in air entrainment; larger air content implies variability in the results of the compressive strength and elastic modulus tests; concrete with higher aggregate levels presented higher carbonation speed, for the same entrained air content; thermal conductivity is inversely proportional to the air entrained content in concrete, and as lower was the aggregate content, lower was the thermal conductivity; the increase of air content in concrete promotes increase in the pores diameter and reduction of the incidence of spherical pores.
117

Experimentální ověření vlivu typu vláken na chování vláknobetonů / Experimental Investigation of the Influence of the Type of Fibres on the Behaviour of Fibre Concrete

Hanuš, Petr January 2019 (has links)
This diploma thesis deals with the comparison of different properties of fibre-reinforced concrete according to the type of fibres. The main monitored property is flexural strength, tested on prisms with a cross section of 150x150 mm and a length of 600 mm. Four concretes of natural aggregate and four concrete of lightweight aggregate were prepared for the experiment. There were 2 reference concrete and 6 fibre-reinforced concrete. Three types of fibres were used: steel, polypropylene and glass. More than 2500 kg of concrete was produced. The aim of the thesis is to assess the influence of fibres on the flexural strength and other characteristics of fibre-reinforced concrete.
118

En funktion- och miljöpåverkansanlays av materialet isobetong / A Property and Environmental Analysis of the Material Isobetong

Rosencrantz, Eric, Saether, Oskar January 2020 (has links)
Byggbranschen utvecklas konstant, strävan efter att utveckla nya och effektivare material ärstor. Några av de viktigaste egenskaperna som byggsektorn eftersöker är hög hållfasthet, lågvärmekonduktivitet och låg miljöpåverkan.Isobetong är ett nyligen framtaget material. Det är en typ av skumbetong med egenskaper ochfunktioner som skiljer sig från traditionell skumbetong ur hänseende på hållfasthet,värmekonduktivitet och miljöpåverkan.Syftet med denna undersökning är att identifiera Isobetongens karakteristiska egenskaper ochjämföra de med egenskaper av konkurrerande material. Resultatet föreslås tydliggöramaterialets styrkor och vidare utgöra en grund för fortsatt undersökning samt främja enutökad användning. De frågor vilket undersökningen formas kring är ’Vad har materialet förmiljöpåverkan?’ och ’Hur jämför sig materialet mot mineralull och cellplast gällande funktionoch miljöpåverkan?’.Resultatet visar att miljöpåverkan av materialet Isobetong varierar från 65,5 kg CO2-ekvivalenter per kubikmeter för dess produkt med lägst densitet, upp till 230,7 kg CO2-ekvivalenter per kubikmeter för produkten med högst densitet. Beräkningarna som utförts ijämförande syfte tyder på att Isobetong i genomsnitt inte är likställd med cellplast ellermineralull inom områdena för densitet, värmekonduktivitet och miljöpåverkan. Resultatet förtryckhållfastheten av Isobetong ger ett betydligt högre värde än de övriga materialen.Slutsatsen är att relativt mot de jämförda materialen kan inte Isobetong konkurrera med varesig cellplast- eller mineralullsisoleringar då högre krav ställs på densitet, värmekonduktivitetoch miljöpåverkan. I projekt där en god tryckhållfasthet krävs har Isobetong en klar fördel. / The construction industry is continuously developing, the strive to develop new and moreefficient materials is great. In the industry, some of the most sought for properties of theimproved materials are high strength, low thermal conductivity, and low environmentalimpact.Isobetong is a recently developed material. It is a variety of foam concrete with properties thatdiffer from traditional foam concrete regarding strength, thermal conductivity, andenvironmental impact.The purpose of this analysis is to identify characteristic properties of Isobetong and tocompare them to the properties of competitive materials. The results are proposed to clarifythe material’s strengths and to furthermore act as a foundation for continued research as wellas encouraging an increased usage. The questions the analysis is based on are ‘What is theenvironmental impact of the material?’ and ‘How does the material compare to mineral wooland polystyrene?’.The result displays an environmental impact of the material Isobetong to vary between 65,5kg CO2-equivalents per cubic meter for the product with the lowest density, up to 230,7 kgCO2-equivalents per cubic meter for the product with the highest density. The computationsthat have been completed for comparative purposes indicates that Isobetong on average is notequal to polystyrene or mineral wool in areas of density, thermal conductivity, orenvironmental impact. The result for the compressive strength of Isobetong yield aconsiderably higher value than the other materials.The conclusion is that relative to the compared materials is Isobetong unable to compete withneither polystyrene or mineral wool insulations when higher requirements are set for density,thermal conductivity, and environmental impact. For projects that require a notablecompressive strength does Isobetong show a clear advantage.
119

SPP 1542: Leicht Bauen mit Beton: Grundlagen für das Bauen der Zukunft mit bionischen und mathematischen Entwurfsprinzipien (Abschlussbericht)

Scheerer, Silke, Curbach, Manfred 14 June 2022 (has links)
Bewehrter Beton ist das heutzutage am meisten verwendete Baumaterial. Es ist universell und preiswert nahezu überall auf der Welt herstellbar. Damit einhergehen allerdings ein hoher CO2-Ausstoß und ein beträchtlicher Verbrauch an natürlichen Ressourcen. Im DFG-Schwerpunktprogramm 1542 wurden deshalb verschiedenste Ansätze erforscht, wie das Material effizienter eingesetzt und damit der Betonbau zukunftsfähig gemacht werden kann. Im vorliegenden Abschlussbericht zum SPP 1542 „Leicht Bauen mit Beton“ (gefördert von 2011 bis 2022) werden die wichtigsten Ergebnisse vorgestellt.:S. Scheerer, M. Curbach: Vorwort | Preface S.13 Teil 1: SPP-Projekte | Part 1: SPP projects A. M. Bauer, M. Breitenberger, K.-U. Bletzinger: Nichtlineare Optimierung geometrisch definierter Fugen von räumlich gekrümmten Betonfertigteilen mit isogeometrischen Verfahren | Non-linear optimization of geometrically defined joints of spatially curved prefabricated concrete elements with isogeometric analysis S.18 L. Ledderose, S. Lehmberg, F. Wirth, H. Kloft, H. Budelmann: Entwicklung neuartiger Verbindungen für komplexe Stab-, Flächen- und Raumtragelemente aus UHPFRC | Development of novel jointing systems for complex beam surface and spatial elements made of UHPFRC S. 50 J. D. van der Woerd, J. Hegger, R. Chudoba: Entwurf und Herstellung von dünnwandigen Faltwerken aus zementbasierten Verbundwerkstoffen | Design and construction of folded plate structures made of novel cementitious composites S. 90 A. Schmidt, M. Curbach: Querschnittsadaption für stabförmige Druckbauteile | Cross sectional adaption for rod-shaped elements in compression S. 118 M. Frenzel, K. Farwig, M. Curbach: Leichte Deckentragwerke aus geschichteten Hochleistungsbetonen | Lightweight ceiling structures made of layered high-performance concrete S. 144 S. Baron, J. Mainka, H. W. Hoffmeister, K. Dröder, H. Kloft: Non-Waste-Wachsschalungen: Neuartige Präzisions-Schalungen aus 100 % recycelbaren Industrie-Wachsen zur Herstellung von geometrisch komplexen Beton-Bauteilen | Non-Waste-Wax-Formwork: Novel precise formwork-technology on basis of 100% recyclable industrial wax for the fabrication of geometrically complex concrete elements S. 170 D. Busse, M. Empelmann: Ultraleichte, dünnwandige stabförmige Betonhohlbauteile | Ultra-light, thin-walled hollow concrete members S. 196 M. Henke, O. Fischer: Formoptimierte filigrane Stäbe aus UHPC und korrosionsfreier CFK-Bewehrung für variable räumliche Stabtragwerke | Shape optimized filigree rods made of UHPC and non-corrosive CFRP reinforcement for variable three-dimensional trusses S. 226 D. Schmeer, M. Wörner, H. Garrecht, O. Sawodny, W. Sobek: Effiziente automatisierte Herstellung multifunktional gradierter Bauteile mit mineralischen Hohlkörpern | Efficient automated production of multifunctional graded components with mineral hollow bodies S. 250 S. Illguth, D. Lowke, T. Kränkel, C. Gehlen: Schalentragwerke mit funktionaler Gradierung | Shell structures with functional grading S. 284 D. Weger, D. Talke, D. Lowke, K. Henke, C. Gehlen, S. Winter: Additive Fertigung frei geformter Betonbauteile durch selektives Binden mit calciumsilikatbasierten Zementen | Additive manufacturing of free formed concrete elements by selective binding with calcium silicate based cements S. 300 C.-A. Graubner, U. Knaack, T. Proske, B. Freund, M. Michel, S. Hickert: Grundlagen zur Entwicklung adaptiver Schalungssysteme für frei geformte Betonbauteile | Fundamental research towards an adaptive formwork system development for freeform concrete building components S. 328 A. Stark, J. Hegger: Sandwichbauteile mit gefalteten und gekrümmten Betondeckschichten | Sandwich panels with folded plate and curved concrete facings S.356 W. Jäger: Untersuchungen zu Trageigenschaften von plattenförmigen Betonleichtbauelementen in Kreuz-Kanal-Technologie | Investigations into the load-bearing properties of slab-shaped lightweight concrete elements in CC technology S.390 M. Schneider, H. Andrä, C. Kohlmeyer, S. Oster: Konstruktion und Optimierung von Klebeverbindungen für Platten- und Scheibenbauteile aus hochfestem Beton | Construction and optimization of adhesive joints for plate and shell construction elements composed of high performance concrete S.412 H. Funke, A. Ehrlich, L. Ulke-Winter, C. Petzoldt, S. Gelbrich, L. Kroll: Flexible GFK-Schalungen zur Herstellung von doppelt gekrümmten Beton-Leichtbauelementen mit stabilisierten Abstandsgewirken | Flexible GFRP-formwork for the production of double curved concrete lightweight elements with stabilized spacer fabrics S.436 H. Funke, L. Ulke-Winter, C. Petzoldt, C. Müller, S. Gelbrich, L. Kroll: Gekrümmte Beton-Leichtbauelemente mit bionisch inspirierten Krafteinleitungssystemen durch Einsatz flexibler GFK-Schalungen | Curved lightweight concrete structures with bionic inspired force transmission elements by the use of flexible GFRP-formworks S.452 L. Lohaus, J. Markowski: Wickelverstärkte Hybridrohre | Wrapping-reinforced hybrid tubes S.472 M. Schlaich, A. Goldack, J. P. Osman-Letelier, D. Lordick, K. Noack, M. Friedrich Eichenauer, R. Päßler, M. Pott: Methoden und Werkzeuge für Entwurf und Herstellung schalenartiger und dünnwandiger Betonbauteile mit Regelflächengeometrie | Methods and tools for the design and construction of thin-walled concrete structures with ruled surface geometry S.488 D. Lordick, D. Klawitter, M. Hagemann: Liniengeometrie für den Leichtbau | Line geometry for lightweight structures S.514 C. Kämper, T. Stallmann, P. Forman, J. Schnell, P. Mark: Leichte verformungsoptimierte Schalentragwerke aus mikrobewehrtem UHPC am Beispiel von Parabolrinnen solarthermischer Kraftwerke | Light-weight shape-optimised shell structures made from high-performance concrete for collector modules of parabolic trough power plants S.536 L. Zhou, J. Simon, S. Reese: Modellreduktion und Substrukturtechnik am Beispiel von modularen Schalentragwerken aus ultrahochfestem Beton | Model order reduction and substructures – application to modular shell structures made of ultra-high performance concrete S.590 M. Schnellenbach-Held, J.-E. Habersaat: Leichte Platten aus Beton mit biaxialem Lastabtrag als bionische Strukturen S.610 O. Gericke, D. Kovaleva, W. Haase, W. Sobek: Abfallfreie Herstellung von Betonbauteilen durch die Verwendung einer gefrorenen Sandschalung | Waste-free production of concrete components by means of a frozen sand formwork S.626 M. Wörner, D. Schmeer, H. Garrecht, O. Sawodny, W. Sobek: Optimalstrukturen aus funktional gradierten Betonbauteilen – Entwurf, Berechnung und automatisierte Herstellung | Optimal structures made of functional graded concrete – design, dimensioning and automated production S.642 Teil 2: Demonstratoren und Anschlussprojekte | Part 2: Demonstrators and follow-up projects D. Busse, L. Ledderose: uni-con² – universal concrete construction S.676 C. Müller, H. Funke, S. Gelbrich, L. Kroll: Carbonbeton-Schalendemonstrator | Shell demonstrator out of carbon reinforced concrete S.682 M. Koschemann, S. Scheerer: CarboLight Bridge – eine ultraleichte Konstruktion aus kohlefaserverstärktem und infraleichtem Beton | CarboLight Bridge – an ultra-lightweight construction made of carbon reinforced and infra-lightweight concrete for the German Museum in Munich S.686 S. Scheerer, B. Beckmann, J. Bielak, S. Bosbach, C. Schmidt, J. Hegger, M. Curbach: Konstruktionsstrategien für materialminimierte Carbonbetonstrukturen – Grundlagen für eine neue Art zu bauen | CRC/Transregio 280: Design strategies for material-minimised carbon reinforced concrete structures – principles of a new approach to construction S.700 D. Talke, D. Weger, K. Henke, T. Kränkel, D. Lowke, C. Gehlen, S. Winter: Industrieller 3D-Betondruck durch selektive Zementaktivierung – Verfahren, Material, Anwendungen | Industrial 3D concrete printing by selective cement activation – process, material, applications S.706 D. Schönfelder, H. Funke, S. Gelbrich, L. Kroll: Automatisierte Herstellungstechnologie zur Fertigung von dünnwandigen 3D-geformten Verbundelementen für nachhaltige energie-effiziente Fassadenlösungen – „GreenFACE“ | Automated manufacturing technology for the production of thin-walled 3D-shaped composite elements for sustainable, energy-efficient facade solutions – “GreenFACE“ S.710 A.-C. von der Heid, N. Will, J. Hegger: Weitspannende Sandwichelemente mit vorgespannten Deckschichten aus Carbonbeton | Wide-span sandwich elements with prestressed facings made of carbon reinforced concrete S.714 L. Ledderose, H. Kloft: Magnetische Ausrichtung von Mikro-Stahldrahtfasern in UHPFRC | Magnetic alignment of microsteel fibers in UHPFRC S.720 C. Petzoldt, C. Müller, H. Funke, S. Gelbrich, L. Kroll: Wiederverwendbare flexible GFK-Schalungen zur Herstellung von doppelt gekrümmten Beton-Leichtbauelementen | Re-usable and flexible GFRP formwork for the production of double curved concrete lightweight elements S.726 L. Lohaus, J. Markowski, R. Rolfes, F. F. Tritschel: UHFB-Drucktragglieder (basierend auf wickelverstärkten Hybridrohren) in voll digital datengestützter Fließfertigung als Basis für eine modulare Betonbauweise | UHPC compression rods (based on wrapped hybrid tubes) in fully digitally data-supported flow production as the basis for a modular concrete construction method S.734 P. Forman, T. Stallmann, P. Mark, J. Schnell: Auslegung von Parabolrinnen für Solarkraftwerke im Originalmaßstab S.738 P. Forman, S. Penkert, P. Mark, J. Schnell: Punktfokussierende Heliostaten aus Hochleistungsbeton | Point-focusing heliostats made from high-performance concretes S. 754 D. Kovaleva, O. Gericke, W. Sobek: Herstellung von biomimetischen und biologisch inspirierten (modularen) Strukturen | Fabrication of biomimetic and biologically inspired (modular) structures S.758 O. Gericke, W. Haase, W. Sobek: Sandschalung zur Herstellung von dünnwandigen Sandwiches aus Carbonbeton | Sand formwork for the production of thin-walled sandwiches made from carbon concrete S.762 D. Nigl, D. Schmeer, W. Haase, B. Schönemann, K. Lenz, S. Steier, O. Sawodny, P. Leistner, L. Blandini, W. Sobek: Integrale Planung und Herstellung von ressourceneffizienten Betonbauteilen aus mineralischer Faserverbundbewehrung und gradiertem Beton | Design and production of resource-efficient concrete components made of mineral fibre composite reinforcement and graded concrete S.766 Teil 3: Koordination | Part 3: Coordination S. Scheerer, M. Curbach: Koordination des SPP 1542 | Coordination of SPP 1542 S.774 / Reinforced concrete is the most widely used building material today. It can be produced universally and cheaply almost anywhere in the world. However, this is accompanied by high CO2 emissions and considerable consumption of natural resources. In the DFG Priority Programme 1542, a wide variety of approaches were therefore investigated to find out how the material can be used more efficiently and thus how concrete construction can be made fit for the future. This final report on SPP 1542 “Concrete Light“ (funded from 2011 to 2022) presents the most important results.:S. Scheerer, M. Curbach: Vorwort | Preface S.13 Teil 1: SPP-Projekte | Part 1: SPP projects A. M. Bauer, M. Breitenberger, K.-U. Bletzinger: Nichtlineare Optimierung geometrisch definierter Fugen von räumlich gekrümmten Betonfertigteilen mit isogeometrischen Verfahren | Non-linear optimization of geometrically defined joints of spatially curved prefabricated concrete elements with isogeometric analysis S.18 L. Ledderose, S. Lehmberg, F. Wirth, H. Kloft, H. Budelmann: Entwicklung neuartiger Verbindungen für komplexe Stab-, Flächen- und Raumtragelemente aus UHPFRC | Development of novel jointing systems for complex beam surface and spatial elements made of UHPFRC S. 50 J. D. van der Woerd, J. Hegger, R. Chudoba: Entwurf und Herstellung von dünnwandigen Faltwerken aus zementbasierten Verbundwerkstoffen | Design and construction of folded plate structures made of novel cementitious composites S. 90 A. Schmidt, M. Curbach: Querschnittsadaption für stabförmige Druckbauteile | Cross sectional adaption for rod-shaped elements in compression S. 118 M. Frenzel, K. Farwig, M. Curbach: Leichte Deckentragwerke aus geschichteten Hochleistungsbetonen | Lightweight ceiling structures made of layered high-performance concrete S. 144 S. Baron, J. Mainka, H. W. Hoffmeister, K. Dröder, H. Kloft: Non-Waste-Wachsschalungen: Neuartige Präzisions-Schalungen aus 100 % recycelbaren Industrie-Wachsen zur Herstellung von geometrisch komplexen Beton-Bauteilen | Non-Waste-Wax-Formwork: Novel precise formwork-technology on basis of 100% recyclable industrial wax for the fabrication of geometrically complex concrete elements S. 170 D. Busse, M. Empelmann: Ultraleichte, dünnwandige stabförmige Betonhohlbauteile | Ultra-light, thin-walled hollow concrete members S. 196 M. Henke, O. Fischer: Formoptimierte filigrane Stäbe aus UHPC und korrosionsfreier CFK-Bewehrung für variable räumliche Stabtragwerke | Shape optimized filigree rods made of UHPC and non-corrosive CFRP reinforcement for variable three-dimensional trusses S. 226 D. Schmeer, M. Wörner, H. Garrecht, O. Sawodny, W. Sobek: Effiziente automatisierte Herstellung multifunktional gradierter Bauteile mit mineralischen Hohlkörpern | Efficient automated production of multifunctional graded components with mineral hollow bodies S. 250 S. Illguth, D. Lowke, T. Kränkel, C. Gehlen: Schalentragwerke mit funktionaler Gradierung | Shell structures with functional grading S. 284 D. Weger, D. Talke, D. Lowke, K. Henke, C. Gehlen, S. Winter: Additive Fertigung frei geformter Betonbauteile durch selektives Binden mit calciumsilikatbasierten Zementen | Additive manufacturing of free formed concrete elements by selective binding with calcium silicate based cements S. 300 C.-A. Graubner, U. Knaack, T. Proske, B. Freund, M. Michel, S. Hickert: Grundlagen zur Entwicklung adaptiver Schalungssysteme für frei geformte Betonbauteile | Fundamental research towards an adaptive formwork system development for freeform concrete building components S. 328 A. Stark, J. Hegger: Sandwichbauteile mit gefalteten und gekrümmten Betondeckschichten | Sandwich panels with folded plate and curved concrete facings S.356 W. Jäger: Untersuchungen zu Trageigenschaften von plattenförmigen Betonleichtbauelementen in Kreuz-Kanal-Technologie | Investigations into the load-bearing properties of slab-shaped lightweight concrete elements in CC technology S.390 M. Schneider, H. Andrä, C. Kohlmeyer, S. Oster: Konstruktion und Optimierung von Klebeverbindungen für Platten- und Scheibenbauteile aus hochfestem Beton | Construction and optimization of adhesive joints for plate and shell construction elements composed of high performance concrete S.412 H. Funke, A. Ehrlich, L. Ulke-Winter, C. Petzoldt, S. Gelbrich, L. Kroll: Flexible GFK-Schalungen zur Herstellung von doppelt gekrümmten Beton-Leichtbauelementen mit stabilisierten Abstandsgewirken | Flexible GFRP-formwork for the production of double curved concrete lightweight elements with stabilized spacer fabrics S.436 H. Funke, L. Ulke-Winter, C. Petzoldt, C. Müller, S. Gelbrich, L. Kroll: Gekrümmte Beton-Leichtbauelemente mit bionisch inspirierten Krafteinleitungssystemen durch Einsatz flexibler GFK-Schalungen | Curved lightweight concrete structures with bionic inspired force transmission elements by the use of flexible GFRP-formworks S.452 L. Lohaus, J. Markowski: Wickelverstärkte Hybridrohre | Wrapping-reinforced hybrid tubes S.472 M. Schlaich, A. Goldack, J. P. Osman-Letelier, D. Lordick, K. Noack, M. Friedrich Eichenauer, R. Päßler, M. Pott: Methoden und Werkzeuge für Entwurf und Herstellung schalenartiger und dünnwandiger Betonbauteile mit Regelflächengeometrie | Methods and tools for the design and construction of thin-walled concrete structures with ruled surface geometry S.488 D. Lordick, D. Klawitter, M. Hagemann: Liniengeometrie für den Leichtbau | Line geometry for lightweight structures S.514 C. Kämper, T. Stallmann, P. Forman, J. Schnell, P. Mark: Leichte verformungsoptimierte Schalentragwerke aus mikrobewehrtem UHPC am Beispiel von Parabolrinnen solarthermischer Kraftwerke | Light-weight shape-optimised shell structures made from high-performance concrete for collector modules of parabolic trough power plants S.536 L. Zhou, J. Simon, S. Reese: Modellreduktion und Substrukturtechnik am Beispiel von modularen Schalentragwerken aus ultrahochfestem Beton | Model order reduction and substructures – application to modular shell structures made of ultra-high performance concrete S.590 M. Schnellenbach-Held, J.-E. Habersaat: Leichte Platten aus Beton mit biaxialem Lastabtrag als bionische Strukturen S.610 O. Gericke, D. Kovaleva, W. Haase, W. Sobek: Abfallfreie Herstellung von Betonbauteilen durch die Verwendung einer gefrorenen Sandschalung | Waste-free production of concrete components by means of a frozen sand formwork S.626 M. Wörner, D. Schmeer, H. Garrecht, O. Sawodny, W. Sobek: Optimalstrukturen aus funktional gradierten Betonbauteilen – Entwurf, Berechnung und automatisierte Herstellung | Optimal structures made of functional graded concrete – design, dimensioning and automated production S.642 Teil 2: Demonstratoren und Anschlussprojekte | Part 2: Demonstrators and follow-up projects D. Busse, L. Ledderose: uni-con² – universal concrete construction S.676 C. Müller, H. Funke, S. Gelbrich, L. Kroll: Carbonbeton-Schalendemonstrator | Shell demonstrator out of carbon reinforced concrete S.682 M. Koschemann, S. Scheerer: CarboLight Bridge – eine ultraleichte Konstruktion aus kohlefaserverstärktem und infraleichtem Beton | CarboLight Bridge – an ultra-lightweight construction made of carbon reinforced and infra-lightweight concrete for the German Museum in Munich S.686 S. Scheerer, B. Beckmann, J. Bielak, S. Bosbach, C. Schmidt, J. Hegger, M. Curbach: Konstruktionsstrategien für materialminimierte Carbonbetonstrukturen – Grundlagen für eine neue Art zu bauen | CRC/Transregio 280: Design strategies for material-minimised carbon reinforced concrete structures – principles of a new approach to construction S.700 D. Talke, D. Weger, K. Henke, T. Kränkel, D. Lowke, C. Gehlen, S. Winter: Industrieller 3D-Betondruck durch selektive Zementaktivierung – Verfahren, Material, Anwendungen | Industrial 3D concrete printing by selective cement activation – process, material, applications S.706 D. Schönfelder, H. Funke, S. Gelbrich, L. Kroll: Automatisierte Herstellungstechnologie zur Fertigung von dünnwandigen 3D-geformten Verbundelementen für nachhaltige energie-effiziente Fassadenlösungen – „GreenFACE“ | Automated manufacturing technology for the production of thin-walled 3D-shaped composite elements for sustainable, energy-efficient facade solutions – “GreenFACE“ S.710 A.-C. von der Heid, N. Will, J. Hegger: Weitspannende Sandwichelemente mit vorgespannten Deckschichten aus Carbonbeton | Wide-span sandwich elements with prestressed facings made of carbon reinforced concrete S.714 L. Ledderose, H. Kloft: Magnetische Ausrichtung von Mikro-Stahldrahtfasern in UHPFRC | Magnetic alignment of microsteel fibers in UHPFRC S.720 C. Petzoldt, C. Müller, H. Funke, S. Gelbrich, L. Kroll: Wiederverwendbare flexible GFK-Schalungen zur Herstellung von doppelt gekrümmten Beton-Leichtbauelementen | Re-usable and flexible GFRP formwork for the production of double curved concrete lightweight elements S.726 L. Lohaus, J. Markowski, R. Rolfes, F. F. Tritschel: UHFB-Drucktragglieder (basierend auf wickelverstärkten Hybridrohren) in voll digital datengestützter Fließfertigung als Basis für eine modulare Betonbauweise | UHPC compression rods (based on wrapped hybrid tubes) in fully digitally data-supported flow production as the basis for a modular concrete construction method S.734 P. Forman, T. Stallmann, P. Mark, J. Schnell: Auslegung von Parabolrinnen für Solarkraftwerke im Originalmaßstab S.738 P. Forman, S. Penkert, P. Mark, J. Schnell: Punktfokussierende Heliostaten aus Hochleistungsbeton | Point-focusing heliostats made from high-performance concretes S. 754 D. Kovaleva, O. Gericke, W. Sobek: Herstellung von biomimetischen und biologisch inspirierten (modularen) Strukturen | Fabrication of biomimetic and biologically inspired (modular) structures S.758 O. Gericke, W. Haase, W. Sobek: Sandschalung zur Herstellung von dünnwandigen Sandwiches aus Carbonbeton | Sand formwork for the production of thin-walled sandwiches made from carbon concrete S.762 D. Nigl, D. Schmeer, W. Haase, B. Schönemann, K. Lenz, S. Steier, O. Sawodny, P. Leistner, L. Blandini, W. Sobek: Integrale Planung und Herstellung von ressourceneffizienten Betonbauteilen aus mineralischer Faserverbundbewehrung und gradiertem Beton | Design and production of resource-efficient concrete components made of mineral fibre composite reinforcement and graded concrete S.766 Teil 3: Koordination | Part 3: Coordination S. Scheerer, M. Curbach: Koordination des SPP 1542 | Coordination of SPP 1542 S.774
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Konstrukční vlastnosti ultralehkých betonů a jeho optimální využití v konstrukcích / Structural Properties of Ultralight Concrete and its Optimal Application in Structures

Kadlec, Jaroslav January 2017 (has links)
This doctoral thesis deals with design of three variants of ultra lightweight concrete (ULC) and their mechanical properties. The ULC usually has the dry density of 900-1200 kg/m3 and it is possible to use it for load bearing structures. Low density of ULC is achieved by replacing heavy aggregate for lightweight aggregate. The lightweight aggregate is known under the trade name Liapor in the Czech Republic. To achieve density below 1000 kg/m3, an aeration of the paste has to be done. An exchange of heavy aggregate for lightweight aggregate results in a very fragile behavior of ULC. A great attention is paid to bond strength between concrete and reinforcing steel in the thesis. In addition to the standard test of bond strength testing by pull-out, a modified pull-out test is designed, which includes the effect of minimum reinforcement cover. The mentioned test more precisely simulates a real behaviour of the structure exposed to bending moment. The doctoral thesis tries to point out on different parameters between measured data and the applicable standard for the design of load-bearing structures.

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