A maioria dos edifícios de concreto pré-moldado, construídos no Brasil e no exterior, é constituída por lajes alveolares. Este trabalho considera o estudo da continuidade dessas lajes. No cálculo desses elementos, a prática comum é considerá-los como simplesmente apoiados. Para melhorar o desempenho, é possível promover a continuidade nos apoios intermediários. Isso pode ser feito colocando armadura na região tracionada da ligação, no interior da capa, ou através de barras concretadas dentro dos alvéolos. O objetivo deste trabalho é investigar o comportamento de pavimentos formados por lajes alveolares com continuidade, com armadura na capa. Para isso, foi realizado um estudo envolvendo análise teórica e experimental em três modelos. Esses modelos, em escala real, foram submetidos a um carregamento transversal, distribuído de forma linear. Os estudos teóricos consideraram uma simulação numérica com elementos de viga e a fórmula de Branson para descrever o comportamento não linear físico do material. Além disso, foram avaliadas as expressões dos principais códigos nacionais e internacionais, no que diz respeito à ruptura por cisalhamento da seção transversal e da interface laje-capa. Os resultados da análise experimental indicaram que o modelo 1 rompeu por cisalhamento da seção transversal, com o mecanismo de tração diagonal do concreto. O modelo 2 apresentou ruptura por cisalhamento da interface. No modelo 3, a ruptura foi por flexão. O comportamento dos modelos ensaiados foi governado pela fissuração da capa na região de momento negativo. A análise teórica com elementos de barra representou de forma satisfatória o comportamento dos modelos ensaiados. As únicas formulações que apresentaram resultados coerentes com os três ensaios foram: EUROCODE 2:2004, para o cálculo da resistência ao cisalhamento da interface, e FIB MODEL CODE 2010, para o cálculo da resistência ao cisalhamento da seção transversal. Conclui-se que a continuidade melhora o desempenho das lajes alveolares, uma vez que reduz os deslocamentos no meio do vão e aumenta a capacidade de carga. / Most buildings of precast concrete built in Brazil and abroad consist of hollow core slabs. This paper considers the study of the continuity of these slabs. In design of these elements the common practice is to consider them as simply supported. To improve the performance it is possible to promote the continuity in the intermediate supports. This can be done by placing reinforcement in the tensioned region of the connection, inside the topping, or by bars concreted inside the voids. The aim of this work is to investigate the behavior of hollow core floors with continuity, with reinforcement in the topping. For this, a study involving theoretical and experimental analysis was conducted in three models. The full-scale models were subjected to a transverse loading distributed linearly. The theoretical studies have considered a numerical simulation with beam elements and the Branson formula to describe the physical nonlinear behavior of the material. Furthermore, the specifications of the major Brazilian and international codes were evaluated, with respect to failure by shear of the cross section and the slab-topping interface. The results of the experimental analysis indicated that the model 1 failed by shear of the cross section with the mechanism of diagonal tension of the concrete. Model 2 presented shear failure of the interface. In model 3, the failure was by flexure. The behavior of the tested models was ruled by cracking of the topping in region of negative bending moment. Theoretical analysis with beam elements represented satisfactorily the behavior of the tested models. The only formulations that presented consistent results with the three tests were: EUROCODE 2:2004, to calculate the shear strength of the interface, and FIB MODEL CODE 2010, for calculating of the shear strength of the cross section. It is concluded that the continuity improves the performance of the hollow core slabs, as it reduces the displacements at mid-span and increases the bearing capacity.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Numerical simulations are presented in this work of precast slabs with lattice reinforcement joists with the goal to provide contributions to the structural analysis of this type of slab. An evaluation has been made on the differences between two structural models (isolated beam and grid equivalent) and between two types of analysis (NBR 6118 modified linear analysis and nonlinear analysis with moment-curvature relationships). Applying the grid model equivalent, the influence of the amount of transverse ribbing was also evaluated, especially in deflections checks at Service Limit State. In order to do this, numerical simulations were conducted on precast slabs with lattice reinforcement joists with one, two, three, five and nine transverse ribbing, for each type of analysis. Comparisons of results have enabled several observations, among which stand out the positive effect of the inclusion of transverse ribs, with an average reduction of 29% between the deflections obtained from nonlinear analysis in relation to the modified linear analysis, which is commonly used by designers. / Neste trabalho foram realizadas simulações numéricas de lajes pré-fabricadas com vigotas treliçadas com o objetivo fornecer contribuições para a análise estrutural desse tipo de laje. Foram avaliadas as diferenças existentes entre dois modelos estruturais (viga isolada e grelha equivalente) e entre dois tipos de análise (análise linear modificada conforme NBR 6118 e análise não linear com relações momento-curvatura). Com o emprego do modelo de grelha equivalente, avaliou-se também a influência da quantidade de nervuras transversais, principalmente nas verificações de flechas em Estado Limite de Serviço. Para tal, foram realizadas simulações numéricas em lajes pré-fabricadas treliçadas com uma, duas, três, cinco e nove nervuras transversais, para cada tipo de análise. As comparações de resultados permitiram diversas constatações, dentre as quais se destacam o efeito positivo da inclusão de nervuras transversais, com uma redução média de 29% entre as flechas obtidas da análise não linear em relação às da análise linear modificada, a qual é comumente utilizada pelos projetistas.

Submitted by Jakeline Ortega (jakortega@unoeste.br) on 2018-09-21T18:11:45Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Jacqueline Roberta Tamashiro - resumo.pdf: 51113 bytes, checksum: 54bab18aa252772921b9b51e3a002aec (MD5) / Made available in DSpace on 2018-09-21T18:11:45Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Jacqueline Roberta Tamashiro - resumo.pdf: 51113 bytes, checksum: 54bab18aa252772921b9b51e3a002aec (MD5) Previous issue date: 2018-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The process of industrialization, population growth and globalization have led, over the decades, to the increase of industrial activities and intensive and mechanized agriculture, which consequently triggered in disorderly urbanization and increased consumption. These demands have generated until the present day, numerous environmental problems, ranging from the exploratory extraction of natural resources, many of them almost extinct, to the disposal of the residues generated by the manufactured products. This scenario has its aggravating, irregular accumulation of this waste. The construction industry uses non-renewable raw materials in abundance, consuming a large amount of energy in the extraction of inputs, in the production of materials and in the transportation of both. Appropriate treatment and recycling of the generated waste may be the most viable to stop the exploration of degraded areas caused by the disordered extraction. This research aims at the mechanical fabrication and characterization of recycled concrete prototypes and precast concrete panels from Presidente Prudente, and vinasse, a by-product of a sugar and alcohol mills in the Western Region of the State of São Paulo. The methodological process involves the sampling of the recycled concrete aggregate (RCA) and the characterization of the raw material (RCA, cement, sand and gravel) using grain size distribution, grains form, specific mass, water absorption and swelling tests. In sequence, the step manufacturing different traits reproduced in many lots of samples, as well as the physical characterization of the fresh mass by the slump test; setting time of paste (Vicat), pH value and the physical characterization of the test specimens through resistance to mechanical compression strength and mass monitoring. Subsequently, it follows the stage of the manufacture of new test specimens of the trace that presented better results in the previous stage. This trait was physically characterized by porosity; (X-Ray Diffraction (XRD), Fourier Transform Infrared Absorption, Attenuated Total Reflectance (ATR-FTIR)), optical microscopy, Scanning Electron Microscopy (SEM). Finally, the last step involved the fabrication of the prototype of the precast concrete panels and the physical tests (mass monitoring, strength of the surface hardness by the sclerometer and flexural tensile strength in a prismatic prototype). The results indicate the feasibility of use as a constructive material, they also indicate the possibility of minimizing the environmental impacts, by reusing them within the civil construction cycle. / O processo de industrialização, o crescimento populacional e a globalização acarretaram, ao longo das décadas, no aumento das atividades industriais e na agricultura intensiva e mecanizada, que por consequência, desencadearam na urbanização desordenada e no maior consumo. Tais demandas geraram até os dias atuais inúmeros problemas ambientais, que envolvem desde a extração exploratória de recursos naturais, muitos dos quais quase extintos, até o descarte dos resíduos gerados pelos produtos fabricados. Este cenário tem seu agravante, o acúmulo irregular destes resíduos. A indústria da construção civil utiliza em abundância matéria-prima não renovável, consome grande quantidade de energia na extração de insumos, na produção de materiais e no transporte de ambos. O tratamento adequado e a reciclagem dos resíduos gerados pode ser o meio mais viável para cessar a exploração de áreas degradadas provocadas pela extração desordenada. Esta pesquisa visa a fabricação e caracterização mecânica de protótipos e placas pré-moldadas de concreto reciclado do descarte de obras da construção civil, de Presidente Prudente e, vinhaça, subproduto de uma usina de açúcar e álcool da Região Oeste do Estado de São Paulo. O processo metodológico contempla a amostragem do agregado de resíduo de concreto (ARC) e a caraterização da matéria-prima (ARC, cimento, areia e brita basáltica) através das técnicas de granulometria, formato dos grãos, massa específica, absorção de água e ensaio de inchamento. Em sequência, a etapa fabricação de diferentes traços reproduzidos em lotes de corpos de prova, bem como a caracterização física da massa fresca pelas técnicas de consistência e abatimento (slump test); tempo de pega da pasta (Vicat) e potencial hidrogeniônico (pH) e a caracterização física dos corpos de prova via resistência à compressão mecânica e monitoramento da massa. Posteriormente, segue a etapa da fabricação de novos corpos de prova do traço que apresentou melhores resultados na etapa anterior. Este traço foi caracterizado fisicamente pelas técnicas de porosidade ou índice de vazios superficiais; caracterização estrutural (Microscopia Ótica (MO), Microscopia Eletrônica de Varredura (MEV), Difração de Raios-x (DRX), Absorção no infravermelho com transformada de Fourier modo ATR (ATR-FTIR)). Por fim, na última etapa compreendeu a fabricação do protótipo da placa pré-moldada e os ensaios físicos da mesma (avaliação da dureza superficial pelo esclerômetro de reflexão e resistência à tração na flexão em um protótipo prismático). Os resultados apresentados indicam a viabilidade de utilização como um material construtivo, indicam ainda a possibilidade de minimização dos impactos ambientais, através da reutilização dos mesmos dentro do ciclo da construção civil.

Neste trabalho foi feito um estudo de uma argamassa especial, à base de cimento e acrescida de vermiculita, látex e fibras curtas (PVA e vidro), visando a sua utilização em ligações entre elementos de concreto pré-moldado. Realizaram-se ensaios de corpos-de-prova cilíndricos de 50 mm x 100 mm para a determinação das características do compósito, tais como: resistência à compressão, resistência à tração e módulo de elasticidade. Foram moldados 20 traços do compósito, variando as quantidades de cada um dos materiais. Foram realizados ensaios de compressão em placas de espessuras 5, 10 e 20 mm para determinação da rigidez (relação entre a tensão e a deformação específica) e do afundamento pela aplicação de carga concentrada. Também foram realizados ensaios de ligações de blocos de concreto, com e sem almofada na emenda. Com base nos ensaios realizados, notou-se que ao se utilizar maiores quantidades de vermiculita, a tendência era de diminuir as resistências à compressão e à tração e também o módulo de elasticidade; entretanto, com a adição de látex e, sobretudo, de uma quantidade considerável de fibra à mistura, sua resistência praticamente se igualava à resistência do corpo sem vermiculita com a vantagem de evitar fissuras ou lascamento, tornando-se adequado para ser utilizado como elemento de apoio em ligações de concreto pré-moldado. Notou-se um acréscimo de resistência à compressão superior a 30% ao se utilizar almofada na emenda nos casos em que não há excentricidade nas ligações entre blocos de concreto. / This research deals with a special mortar made with cement, which it was added vermiculite, latex and short fibers (PVA and glass) to be used in connections between elements of precast concrete. It was made cylindrical samples of 50 mm x 100 mm for the determination of the characteristics of the composite, such as: compression strength, tensile strength and modulus of elasticity. It was made 20 mixtures of the composite, varying the amounts of each one of the materials. Compression tests were made in plates with thickness of 5, 10 e 20 mm for determination of the stiffness (relationship between stress and specific deformation) and deformation due the application of concentrated load. Connections tests on concrete blocks were also made, with cushion and without it in the connection. Based in these tests, it was noticed that when using larger amounts of vermiculite, the tendency was of reducing the compression strength and tensile strength and the modulus of elasticity too; however, with the addition of latex and, above all, of a considerable amount of fiber to the mixture, your strength practically was equaled to the strength of the material without vermiculite with the advantage of avoiding cracks or split, becoming adequate to be used as cushion in precast concrete connections. It was noticed an increment of larger compression strength than 30% when using cushion in the connection in the cases in that there is not eccentricity in the connections between concrete blocks.

The diploma thesis deals with a new building of a single-storey production object, which is made as a precast concrete frame with a lightweight cladding. Part of the new building is also facilities for employees and its administrative staff, which is also based on precast concrete frame divided into two floors. Cladding is made as masonry with ventilated facade. The internal division of buildings is made by plasterboard partitions. The project is located in the industrial zone Košíkov near Velká Bíteš.

The diploma thesis deals with a project of a pedestrian bridge across the valley. At first, there was a comparison of three options of a bridge, then the option of a prestressed concrete band was selected. The main aim of the diploma thesis is the design of the construction, the creation of a model in the programme Ansys 12.1 and the subsequent assessment in accordance with the current regulations.

Diplom thesis is about design of an office building. Building floor plan is designed as a rectangle. The building consists of four floors. Roofing the object is solved by a flat roof with strips of m-PVC. The purpose of the internal arrangement is to be able to lease office space to individual firms on the floor. On the first floor is situated an entrance hall with space for the doorman and staircase area. At the hall is also a personal elevator and utility room. These spaces are common to all tenants. In the space for offices are located toilets for women, for men and one toilet for the disabled. Kitchen with lounge and six offices. These spaces are connected with single corridor. The other floors are connected to administrative with hall, which houses a staircase and an elevator. In office spaces 2.NP. 3.NP and 4.NP are located toilets for women, for men and one toilet for the disabled. Kitchen with lounge, utility room and nine offices. These spaces are connected with single corridor. From these levels, there is also access to the evacuation staircase, which is designed according to the requirements for fire protection. On the 4.NP in the utility room is located auditing roof ascent. The project was developed in the educational version of ArchiCAD 17 and processed in accordance with the requirements of a layout, architectural design, structural design, proper and safe use of the building.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering; and, (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: p. 175-178. / by Joseph Gilmary Burns. / M.S.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21364号 / 工博第4523号 / 新制||工||1704(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 西山 峰広, 教授 竹脇 出, 准教授 倉田 真宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Byggmaterialmarknaden i Sverige uppfattas idag som oligopolisk där ett fåtal företag dominerar en stor del av marknaden. Nya inköpsvägar för material kan öka konkurrensen och förändra villkor för aktörer i branschen. Flera utredningar menar på att import är en sådan inköpsväg som kan förändra den nuvarande prisstrukturen. Men för företag som ser import som en möjlighet kommer även ny problematik som måste hanteras. Företaget Midroc har ett stort intresse i att utreda möjligheten för att köpa in färdiga betongstommar från andra sidan Östersjön. Rapporten syftar främst till att undersöka och utvärdera olika leverantörer av betongelement i utlandet och på så sätt samtidigt undersöka möjligheterna för import. Genom intervjuer, litteraturstudier och enkäter till inköpare samt lokala leverantörer har kritiska faktorer tagits fram. Dessa innefattar bland annat teknisk standard, garantier, transport och risker. Det kom fram tidigt i studien att det finns en diskrepans mellan de tekniska standarder som tillämpas i Sverige jämfört med andra länder. Detta måste naturligtvis tas i särskild hänsyn så att produkterna som köps in är godkända att användas i Sverige. Ett sätt att säkerställa detta är att köpa betongprodukter som är certifierade med BBC-märket. Ett formulär med frågor upprättades, frågorna var menade att ge en inblick i vad företagen erbjuder och hur de arbetar. Prisfrågor har inte tagits med då det var omständigheterna kring ett internationellt inköp som var av störst intresse. Det har dock kommit fram att priset för betongstommar i Baltikum kan vara 20-30 % lägre än de nationella priserna. Företag i Polen och Baltikum kontaktades via telefon och på mejl, dessa fick möjlighet att svara på frågeformuläret. Företagen som svarade hade aktuella projekt i Sverige och hade fortsatt intresse av att utveckla sin marknad. Utifrån svaren som gavs har en leverantörsvärdering tagits fram för att värdera de leverantörer som passar företaget. Syftet var att försöka avgöra om det var lämpligt att gå vidare med leverantören. Det faktum att alla företagen redovisade ett pågående samarbete med flera byggföretag i Sverige, att flera av företagen är både vana och villiga att arbeta enligt allmänna bestämmelser, att de erbjuder helhetslösningar osv. visar på att möjligheterna för lyckad import är goda. / The construction material market in Sweden is considered today to be oligopolistic where few companies dominate the market. New ways of procuring materials could increase the competition and change the terms for all the actors. Studies have shown that import is one of those new ways of procuring materials, thus altering the current price structure. But companies that consider importing materials will face problems that need solving. The company Midroc has shown great interest in investigating the possibility for purchasing precast concrete structural elements from overseas. The main purpose of this report is to investigate the possibilities of importing and evaluating potential suppliers. Through interviews, literature and inquiries to sales managers and local suppliers, important factors have been identified, such as standards, warranties, transportation and financial risk. A significant finding was that there are technical standards that differ between countries which can impede import. One way to surpass this is to look for concrete products which are certified with the BBC mark. A questionnaire was made which was meant to give useful information about what the company offers and how they work. Price was not included due to the fact that the main interest was the circumstances around an international purchase. However, it has emerged that concrete structural elements in the Baltic States could be 20-30 % cheaper than Swedish products. Suppliers in Poland and the Baltic states were phoned and e-mailed. The suppliers that answered were all currently working in Sweden and interested in increasing their export. A supplier assessment was made which is based on the answers. The fact that all companies were currently cooperating with construction companies in Sweden, show that they are familiar with Swedish regulations and often are able to offer an overall solution. This indicates that the possibilities of importing precast concrete elements to Sweden are good.