Dissertations / Theses: 'Concrete word'

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CASAROTTI, ALESSANDRA. "Nomi propri, categorie semantiche, parole astratte e concrete: correlati neurali in pazienti con glioma cerebrale." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/40214.

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Several studies have suggested different neural circuits for different categories of stimuli. The present studies explore in patients submitted to surgical removal of a glioma, the role of cortical and subcortical structures involved in processing abstract and concrete words. In the first study living and non-living objects were investigated. Direct electrical cortical stimulation was used to map naming of living/non-living entities during surgical removal, then subcortical connections for specific categories of objects were investigated. Two different pathways were identified, one for living and one for non-living things. These results constitute a neurophysiological evidence for the critical role of subcortical pathways as part of the neural circuits that represent lexical-conceptual knowledge of different categories of objects. The second study focused on proper names retrieval and its relationship with the uncinate fasciculus. Forty-four patients with a brain tumor in the left frontal or temporal lobe were examined. In 18 of them surgical removal included the uncinate fasciculus. Patients were assessed before surgery, three-seven days after surgery and three months after surgery. This procedure allowed understanding whether there was any difference due to the lesion of uncinate fasciculus. Patients with removal of the uncinate fasciculus were impaired in naming famous faces and objects. In the third study processing of abstract and concrete nouns was investigated. Fifty-six patients with a brain tumor in the left and right frontal or temporal lobe were examined by means of a semantic similarity judgment. The results suggest that the anterior temporal and the left fronto-insular regions are involved in processing abstract words.

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Magwaza, Goodwill. "Dichotic recall indices of lateralized cerebral processing of abstract, concrete and emotional Zulu word stimuli in FS+ and FS- dextrals." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/13485.

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Bibliography: leaves 131-138.
This thesis reports a basic cognitive neuropsychological experiment which employed an original dichotic recall test to assess lateralized cerebral processing of abstract, concrete and emotional Zulu word stimuli among 32 male and 30 female dextral (right- handed) Zulu-speakers, consisting of 14 males and 12 females with sinistral (left-handed) blood relatives (FS+ ~ and 18 males and 18 females with no sinistral blood relatives (FS-). The present dichotic listening experiment investigated whether abstract word stimuli are recalled more poorly or better than either concrete or emotional word stimuli, and whether concrete word stimuli are recalled better or more poorly than emotional word stimuli. It also investigated whether recall of abstract, concrete and emotional word stimuli yield a right ear advantage CREA) or left ear advantage (LEA).

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ORENA, ELEONORA FRANCESCA. "Lemons and Trust: the Contribution of Anesthesia to the Study of the Neural Substrates of Concrete and Abstract Word Processing." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2017. http://hdl.handle.net/10281/142471.

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There is evidence that abstract and concrete words are represented and processed differently in the brain. Numerous studies suggest the activation of a bilateral network for both abstract and concrete words, with a greater involvement of posterior, sensory areas in concrete word processing, and a more focal activation of anterior regions, involved in verbal processing, for abstract words. This Ph.D. thesis aimed at investigating the different neural substrates of concrete and abstract words by studying memory priming during general anesthesia. Implicit memory tasks, in fact, seem to be immune to the concreteness effect and recent neurophysiological studies suggest that conscious and unconscious semantic activation involve similar brain areas. Experiment 1 focused on the priming effect for intraoperatively primed abstract and concrete words in patients under general intravenous (propofol) anesthesia. Considering the specific brain targets of propofol, I hypothesized a stronger priming effect for concrete than for abstract words. Implicit memory for primed words was tested with a three-letter word stem completion test, in which half of the stems referred to primes, and half were foils. Both stimulation and testing were auditory, to avoid cross-modality interference. A control group of patients, who did not receive any intraoperative stimulation, but completed both concrete and abstract word stem completion test, was also recruited. As expected, a priming effect was found for concrete words, since the number of target hits was significantly higher than the number of non target hits. This difference did not apply to abstract words. The abstract experimental group performed comparably to controls. These results support the thesis that abstract word processing relies on the activity of anterior brain areas, as for example the inferior frontal cortex, which are suppressed by propofol. The results would also confirm that priming, investigated through word stem completion, is not a simple perceptual, pre-semantic task, but engages multiple processes, including semantic access. As suggested by electrophysiological studies, semantic access might occur at very early stages of verbal processing, thus explaining a selective intraoperative priming effect for concrete words only. To further investigate these hypotheses, a second experiment was conducted. In experiment 2 the same methodology of experiment 1 was applied, but the volatile anesthetic sevoflurane was used, which is known to lower activity in brain regions located more posteriorly than those suppressed by propofol. The most interesting finding was the presence of a priming effect also for abstract words, which would confirm data from neuroimaging studies of a greater engagement of anterior brain regions in abstract word processing. To better define the involvement of the frontal cortex in the processing of abstract words, a series of patients undergoing awake surgery for brain tumor removal was studied in experiment 3. Patients performed a lexical and a semantic decision task, together with a standard intraoperative cognitive monitoring, during direct cortical stimulation. The fundamental role of the left inferior frontal gyrus in abstract word processing was confirmed.

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Bohinski, Chesla Ann. "The portrait of a word: The use of mental and visual images in the acquisition of form, meaning, and use of Spanish concrete nouns." Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/151680.

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Spanish
Ph.D.
Second language (L2) vocabulary learning is at the core of language learning and use. Studies have shown that native speakers and L2 learners perceive lexical errors as the biggest obstacle in effective communication (Gass & Selinker, 2008). As a result, the learning and teaching of vocabulary must be one of the focal points of L2 learning. This study quantitatively investigates the effectiveness of two vocabulary learning strategies, the keyword method and the visual support method. Using these two strategies, L2 learners can store the word's meaning both visually and linguistically by creating a "dual coding" (Paivio & Desrochers, 1981) of the word. The keyword method is a strategy that utilizes the association of a first language word (a keyword) with the unknown L2 word through the use of a mental image whereas the visual support method is a strategy that utilizes a visual image. In four L2 intact classes over a 6-day treatment period, participants learned 24 Spanish concrete nouns using both the keyword and visual support methods in one of two presentation orders. Using a pre-test, post-test, and delayed post-test design, results indicated that the use of an image, whether mental or visual, increased L2 learners' knowledge of form, meaning, and use of L2 vocabulary. Qualitative analyses of vocabulary notebooks/journals and surveys revealed that participants' preferences for and experiences with each learning method were influenced by individual likes and dislikes of each treatment. Since vocabulary acquisition is such a complex and multi-faceted process (Nation, 2001), educators have the responsibility to implement and encourage the use of various L2 vocabulary teaching and learning strategies. This research thus aims to reveal how an image can be worth a thousand words in the L2 classroom.
Temple University--Theses

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Hilder, Jamie. "Designed words for a designed world : the international concrete poetry movement, 1955-71." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/28752.

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This dissertation positions the International Concrete Poetry movement within its historical moment and links it to the emergence of a new global imaginary around the middle of the 20th century. It makes the argument that contemporaneous social and technological shifts directly influenced the compositional strategies of a group of poets who aimed to transform poetry’s communicative power in a rapidly shifting media environment. By positioning primary materials – poems, manifestos, and statements by the poets themselves – against contemporaneous cultural phenomena across various disciplines, I perform a critical examination that allows for new strategies for engaging work that has historically frustrated readers. I identify in a series of permutational poems the influence of rudimentary computer technology and the implications that technology has for poetic subjectivity. I locate the international character of the movement in modernization projects such as Brasília, and in technologies that held significance for the entire globe, such as reinforced concrete, satellite photography, and nuclear weapons. As concrete poetry takes shape in both books and galleries, I investigate the spatial implications of the work in its various forms, and analyse its often fraught relationship with Conceptual Art, which also presented language in innovative ways though in pursuit of different purposes. Across this terrain my methodological approach oscillates between art history and literary and cultural studies, paying close attention to how the poetry circulated within and imagined global spaces at a time that predated but in some ways initiated the trends we now see more fully developed in current concepts of globalization.

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Mollo, Lesiba George. "Concrete work decision analysis in Bloemfontein." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/19190.

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The purpose of this study was to evolve how to reduce the manifestation of poor decisions that always produce defects and rework. The purpose of the study is predicated on the fact that good decision-making is a fundamental element of improved project delivery in the construction industry. Such decisions determine the accomplishment of performance parameters in each project. However, suboptimal performance, which is pervasive in the construction industry, is often linked to team decisions. To remedy decision-making pitfalls, the concept of Choosing by Advantages (CBA) is promoted by lean construction researchers. CBA is a decision-making system that assists project parties in deciding a course of action among competing alternatives. Case study research design was used for this project to discover the decision-making process adopted by project teams. The results from the study achieved through cross-case analysis shows that concrete defects and rework is often caused by the project team’s decision-making process, which is influenced by the members of the project team because of lack of experience, poor working conditions, and lack of education. The results also show that the decision-making mechanism of the project teams is influenced by the construction method, specification, cost, quality and time. The outcome of the project team’s decision-making process when choosing a concrete type often causes the concrete defects and rework, which can be eliminated through the application of CBA when choosing a concrete type. The application of CBA when choosing concrete type from two alternatives, ready mixed concrete and site batched concrete is driven by the project team. It was discovered from all three cases that ready-mixed concrete had a better score than site-batched concrete when using CBA to compare these two alternatives. The results show that ready-mixed concrete had less chances of causing concrete defects and rework when used or applied per the correct specifications or methods which are detailed in the engineering drawings of the structure. The study proposes that the project team should adopt CBA to improve their decision-making process on site especially when working with concrete.

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De, Mornay Davies Paul. "The semantic representation of concrete and abstract words." Thesis, Royal Holloway, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267987.

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This thesis examines the various approaches which have been taken to investigate the concrete/abstract word distinction both in normal subjects and in patients who, as a result of brain damage, have an impairment of lexical semantic representations. The nature of the definition task as a tool for assessing the semantic representations of concrete and abstract terms was examined. It was found that definitions for abstract words differed from those of concrete words only in style, not in semantic content. The metalinguistic demands of the definition task therefore make it inappropriate for assessing the semantic representations of concrete and abstract terms in patients with any form of language impairment. The performance of four patients with semantic impairments was examined using a variety of tasks designed to assess concrete and abstract word comprehension. While some of the data can be accommodated within the framework of several theories, no single theory can adequately account for the patterns of performance in all four patients. An alternative model of semantic memory is therefore proposed in which concreteness and frequency interact at the semantic level. Jones' Ease of Predication Hypothesis, which states that the difference between concrete and abstract terms can be explained in terms of disproportionate numbers of underlying semantic features (or "predicates") was also investigated. It was found that the ease of predication variable does not accurately reflect either predicate or feature distributions, and is simply another index of concreteness. As such, the validity of this concept as the basis of theories of semantic representation should be questioned. Models based on the assumption of a "richer" semantic representation for concrete words (e.g.: Plaut & Shallice, 1993) are therefore undermined by these data. The possibility that concrete and abstract concepts can be accessed from their most salient predicates and/or features was examined in a series of semantic priming experiments. It was concluded that it is not possible to prime either concrete or abstract concepts from their constituent parts. Significant facilitation only occurred for items in which the prime and target were synonymous and therefore map onto concepts which share almost identical semantic representations. In summary, it is apparent that no current theory of semantic representation can adequately account for the range of findings with regard to the concrete/abstract word distinction. The most plausible account is some form of distributed connectionist model. However, such models are based on unsubstantiated assumptions about the nature of abstract word representations in the semantic network. Alternative proposals are therefore discussed.

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Correia, Juliano. "Avaliação experimental de ligações de peças mistas madeira- concreto e entre peças de madeira com conectores de barra de aço e de concreto." Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/3735.

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This work describes an experimental investigation of Wood-to- concrete and woodto- wood joints for composite members using steel-bar and concrete connectors. In wood concrete joints, symmetric three-member specimens were built, with wood outside pieces and concrete inside. In wood-to-wood joints, both three-member and two-member symmetric specimens were built. The steel-bar connectors consisted of straight pins with heads, cut from the bars, inserted normally to the wood surface and shaped like arches. They were simply driven into the wood, glued with an epoxy adhesive or with load distribution plate in compression side. The concrete connector’s joints are made with concrete-filled mortise. In addition, steel bars, placed normally to the joined pieces, were used to avoid opening and separation of the member during loading. In these connections, variable slope of the mortise and location at one or at both sides of the wood member are used. The specimens were then subjected to an increasing compressive force, and forcedisplacement diagrams were plotted, from which the stiffness were calculated, both of service (Ks) and ultimate limit states (Ks). These results for all connections have shown high values for strength and stiffness. In wood-to-concrete steel-bar connections ductile processes are obtained and the end failure occurs in concrete. In concrete connections, these results have shown that most of the failures occurred in a fragile manner, with stiffness remained approximately constant during the evaluation.
Apresenta-se neste trabalho uma avaliação experimental de ligações de peças mistas madeira-concreto e de peças compostas de madeira, com emprego de conectores de barras de aço e de conectores de concreto. Nas ligações de peças mistas, foram ensaiados corpos-de-prova simétricos com três peças, com peças laterais de madeira e peça central de concreto. Nas ligações entre de peças de madeira, foram ensaiados corpos-de-prova simétricos, com três peças e com duas peças. Os conectores de barras de aço foram executados como pinos retos com cabeça, dispostos normais às peças de madeira e na forma de arco, com fixação na madeira por cravação direta, com emprego de adesivo epóxi ou com auxílio de placa de distribuição de carga no lado comprimido. Os conectores de concreto foram obtidos pelo preenchimento de entalhes executados na madeira e barras transversais de aço, empregadas para impedir a abertura entre as peças ligadas. Os entalhes foram executados com diferentes inclinações, em um único lado ou nos dois lados das peças de madeira. Nos ensaios, os corpos-de-prova foram submetidos à força de compressão crescente, sendo obtidas as resistências, as curvas força x deslocamento relativo e as rigidezes relativas aos estados limites últimos (Ku) e de utilização ou de serviço (Ks). Os resultados indicaram a ocorrência de elevadas resistências e rigidezes para todas as ligações. Nas ligações de peças mistas com conectores de barra de aço ocorreram processos de ruptura com indícios de ductilidade, com rupturas finais no concreto por efeito de compressão-fendilhamento. Nas ligações com conectores de concreto ocorreram processos de ruptura predominantemente frágeis e valores de rigidezes praticamente constantes ao longo do carregamento.

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Luiz, Mariangela Gonçalves. "Medição da umidade no sistema concreto-madeira." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-11112005-164626/.

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A aplicação de um piso de madeira maciça sobre um contrapiso de concreto dá origem a um sistema que une dois materiais com diferentes características higroscópicas, e no qual a movimentação da umidade é ainda um fenômeno pouco conhecido. Visando um melhor entendimento desse fenômeno, a presente pesquisa buscou avaliar diferentes equipamentos para medir o teor de umidade do concreto, desenvolver uma metodologia para quantificar a água evaporável presente no substrato mineral e, a partir desses resultados, sugerir o teor de umidade do substrato mais adequado à aplicação de um revestimento de madeira. Corpos de prova de concreto, preparados com traço 3:1:1 e relação água cimento em torno de 0,5, foram submetidos a secagem ao ar, sendo que a variação do teor de umidade do concreto ao longo do tempo foi acompanhada pela perda de massa e com a utilização de medidores elétricos de umidade do tipo resistência e de contato.. Com o auxílio da análise de regressão foi possível estabelecer equações de correção para as leituras de umidade dos aparelhos. Para a quantificação da água evaporável no concreto, foi desenvolvido um corpo de prova utilizando-se cilindros de MDF com 6,0 cm de comprimento e 4,8 cm de diâmetro, inseridos em tubo de PVC e com uma das extremidades vedada com filme plástico e silicone. O cilindro de MDF mostrou-se um indicador eficiente da presença de água evaporável no concreto, uma vez que as taxas de adsorção pelo MDF puderam ser diretamente correlacionadas às taxas de evaporação pelo concreto. O efeito do adesivo no sistema concreto-madeira foi avaliado através da variação do gradiente de umidade em madeira de Jatobá (Hymenaea sp). Tacos de Jatobá, com dimensões de 100 mm x 80 mm x 18 mm e nos quais foram colocados sensores a 4 mm e a 17 mm de profundidade, foram colados em corpos de prova de concreto utilizando-se adesivo a base de PVA com 60% de sólidos. Os resultados mostraram que a água contida no adesivo não foi totalmente adsorvida pelo taco e o gradiente de umidade no sentido da espessura apresentou relação com o teor de umidade à profundidade de 17 mm, confirmando a hipótese de que existe um fluxo de umidade na interface concreto-madeira.
The application of solid wood flooring over a concrete subfloor originates a system joining two materials with different hygroscopic characteristics, and in which the moisture movement still is a little known phenomena. Looking for the better understanding of moisture relationship in this system, the present research evaluated different equipments to measure concrete moisture content, to develop a methodology to quantify the vaporizable water present in the mineral substrate and, according to these results, to suggest the substrate moisture content more adequate to application of a wooden covering. Sample test of concrete, prepared with trace 3:1:1 and relation water/cement around 0.5, were submitted to air drying and the variation of the concrete moisture content during the process was registered by the mass loss and with the use of electric moisture meters of resistance and contact types. Through regression analysis it was possible to establish equations to correct moisture meters readings. To quantify the vaporizable water present in concrete, a sample test was developed using cylinders of MDF with 6.0 cm of length and 4.8 cm of diameter, inserted in a PVC tube and with one of the extremities closed with plastic film and silicone. The MDF cylinder was an efficient indicator to quantify vaporizable water in the concrete, considering that the moisture adsorption rate of MDF samples could be directly correlated to the concrete evaporation rate. The effect of adhesive in concrete-wood system was evaluated through the variation of moisture content gradient in Jatobá lumber (Hymenaea sp). Flooring samples of Jatobá, with dimensions of 100 mm x 80 mm x 18 mm and moisture sensors inserted at depths of 4 mm and 17 mm, were glued to concrete sample test using a PVA based adhesive with 60% of solids. Results showed that the water contained in the adhesive was not totally adsorbed by the flooring sample and the moisture gradient across sample thickness is correlated to moisture content at depth of 17 mm, what confirm the moisture flow between concrete and wood.

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Gerber, Adam Reynold. "Timber-concrete composite connectors in flat-plate engineered wood products." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57860.

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Timber-Concrete Composite (TCC) systems are comprised of a timber element connected to a concrete slab through a mechanical shear connection. When TCC are used as flexural elements, the concrete and timber are located in compression and tension zones, respectively. A large number of precedents for T-beam configurations exist; however, the growing availability of flat plate engineered wood products (EWPs) in North America in combination with a concrete topping has offered designers and engineers greater versatility in terms of architectural expression and structural and building physics performance. The focus of this investigation was to experimentally determine the properties for a range of proprietary, open source, and novel TCC systems in several Canadian EWPs. Strength and stiffness properties were determined for 45 different TCC configurations based on over 300 small-scale shear tests. Nine connector configurations were selected for implementation in full-scale bending and vibration tests. Eighteen floor panels were tested for elastic stiffness under a quasi-static loading protocol and measurements of the dynamic properties were obtained prior to loading to failure. The tests confirmed that both hand calculations according to the γ-method and more detailed FEM models can predict the basic stiffness and dynamic properties of TCC floors within a reasonable degree of accuracy; floor capacities were more difficult to predict, however, failure did usually not occur until loading reached 10 times serviceability requirements. The research demonstrated that all selected connector configurations produced efficient timber-concrete-composite systems.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Price, Andrew D. F. "An evaluation of production output for in situ concrete work." Thesis, Loughborough University, 1986. https://dspace.lboro.ac.uk/2134/7285.

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The overall aim of this thesis is to develop reliable methods of measuring output levels for construction plant and labour, with a view to establishing realistic output rates for concreting operations. This thesis demonstrates that most of the variability in production rates can be quickly explained, leaving relatively constant levels of output f or individual construction operations (i.e. basic operation times). The primary factors in determining output rates were found to be work rate, delays and waiting caused by poor management, and poor motivation. The latter two items accounted f or more than fifty per cent of the available working time on many sites, whereas work rate varied only slightly. This last finding may be surprising, but the results indicated that when work was being done the effort applied appeared fairly constant to the observer. However, the time spent working was largely dependent upon the level of motivation induced through the payment system. Where a combination of good direct supervision and satisfactory financial incentives were present, high levels of motivation were observed, conversely, low motivation occurred on sites where minimum day-work payments were present. Investigations into several construction trades indicate that work study techniques can be modified to meet the requirements of most construction operations, sites and companies, whether the requirements be a complex synthesis of basic operation times or the more simple determination of site efficiency. The key to this portability lies in the isolation of basic operation times via the application of site efficiency factors. In this thesis, primary work study techniques are identified and discussed. The need for specific construction work study techniques is shown to be of paramount importance. The results from over seventy concrete pours are combined and statistically analysed to produce realistic output rates arid current levels of production. Site factors are combined and statistically analysed to produce a relationship between efficiency and level of remuneration. A comparison is drawn between: the production rates achieved on several sites; and the output rates currently being used in the planning and estimating processes.

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Liang, Li. "Recycling of concrete waste with wood waste through heating compaction." Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-275674.

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Concrete, as primary building material, is widely used in most construction project. For this reason, large amounts of concrete waste were generated from construction and demolition. One way to reuse concrete waste is to use it as backfill material for landfilling and road bases. While the demand for backfill material is decreasing as the basic infrastructure construction gradually completes. Another way to reuse concrete waste is to grind it and use it as aggregate in casting new concrete. However, the reuse as aggregate for casting concrete requires large amount of cement. It is unsustainable because the production of cement causes significant amounts of carbon dioxide emission. How to deal with the concrete waste in a sustainable way is presently an urgent issue. Powder compaction is a new approach to completely recycle concrete waste in an environmentally friendly way. This new method was studied in the Sakai lab of the Institute of Industrial Science, The University of Tokyo. The process consists of crushing and milling concrete waste into a fine powder, filling the powder into moulds and compacting it under high pressure. By this process concrete waste powder can be turned into a solid concrete with mechanical properties so that it has potentials to be used again as a building material. Data from previous studies show that the compacted concrete waste can reach strength for construction but the required compaction pressure is quite high. Wood flour can be added in compaction for improving tensile strength and reducing compaction pressure. Lignin is a wood substance that melts under high temperature, fills gaps and improves bonding between particles. Cellulose from the wood substance functions as fibres which improves tensile strength. Wood waste from production of timber building materials, furniture and other wooden products also forms a larger quantities. Recycling of concrete waste with wooden waste through heating compaction is a potentially sustainable method. This Master thesis presents research on the effect from different production conditions on the bending strength of recycled concrete waste with wood waste through heating compaction. The condition factors studied were compaction duration, compaction pressure, concrete proportion, mixture percentage, temperature and particle size of wood flour. To enhance the water resistance of this recycled product, different water resistance treatments were discussed theoretically. The independence of production condition factors was analysed using a statistic method. Results indicated that within a certain range, an increase in compaction duration, compaction pressure, the percentage of wood waste and temperature improves the bending strength of the recycled products. Using smaller particle size of wood flour cannot improve compaction but contribute to give higher bending strength. The mechanical properties of these recycled products suggest application as non-bearing building material, such as decoration tiles and bricks for partition walls. The application as a structural material is expected in the future as improvement treatments are discovered.

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ORLANDO, Nicola. "Advanced modeling of detachment and joints in concrete and wood." Doctoral thesis, Università degli studi di Ferrara, 2019. http://hdl.handle.net/11392/2487869.

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The prediction of the structures failure is one of the most important and yet challenging tasks in civil engineering. Numerical studies are faster and cheaper than experimental studies. For these reasons, numerical models are useful for researchers. The present work focuses on the Finite Element (FE) simulation of several non-linear 3D engineering problems related to the rehabilitation of concrete and wooden structural elements. In the considered context, the numerical model employed has to be fast, stable and robust to tackle the complexity and the computational burden of the problems to be solved. The numerical method employed for the simulations is a regularized variant of the eXtendend Finite Element Method (XFEM) proposed by Belytschko and coworkers [1]. The computational model, called REgularized XFEM (3D RE-XFEM), has been developed by Benvenuti [2] in order to study strong and weak discontinuities. Initially, it has been used to study the non-linear evolution of discontinuities in 2D plane-stress problem in concrete [3] and concrete-like [4, 5] materials. Recently, the model has been employed to study linear 3D problems involving planar/curved interfaces [6] and inclusions [7]. Since the previous 2D applications proved the stability and the reliability of the RE-XFEM, in this work, the 3D non-linear formulation (3D RE-XFEM) of the method has been implemented into a parallelized FORTRAN code [8] and successfully applied to several engineering problems. The thesis collects the results obtained for the modelling of concrete and wooden beams through the 3D RE-XFEM. In particular, the topics covered by this work can be divided into two main parts: • The first part is devoted to the modelling of the detachment of FRP reinforcements from concrete specimens. Ch. 2 introduces the 3D REXFEM approach for concrete and concrete-like materials. Ch. 3 presents the results obtained in the simulation of the detachment process of FRP plates from concrete blocks published in Ref. [9]. Ch. 4 is devoted to the investigation of FRP reinforced bended beams presented in Refs. [10, 11]. • The second part of the thesis focuses on the simulation of wooden structures. In particular, in Ch. 5 the analyses of end-repaired beams published in Ref. [12] using an orthotropic elasto-damaging model available in literature are discussed. Ch. 6 is devoted to the development of a new unpublished 2D constitutive elasto-damaging plastic model combined with the RE-XFEM for wooden structures. In the end, Ch. 7 summarizes results and significant aspects achieved in this thesis.
La predizione del carico e della modalità di rottura di una struttura è uno degli obiettivi più importanti e impegnativi dell’ingegneria civile. In questo ambito, l’utilizzo di modelli matematici e simulazioni numeriche sta via via assumendo sempre più importanza, visti la maggiore velocità di esecuzione e il minore impatto economico rispetto ai test in laboratorio. Il lavoro in esame si focalizza sulla simulazione agli Elementi Finiti (FE) di diversi problemi non-lineari nel campo 3D relativi ad interventi di riabilitazione su strutture in calcestruzzo e legno. In questo contesto è necessario che i modelli numerici sviluppati siano veloci, stabili e in grado di descrivere correttamente il comportamento del materiale senza aumentare troppo l’onere computazionale richiesto dalla simulazione. Per l’esecuzione delle simulazioni è stata usata una variante regolarizzata del metodo eXtended Finite Element Method (XFEM) proposto da Belytschko e dai suoi collaboratori [1]. Il modello numerico proposto in questo lavoro, denominato REgularized XFEM (3D RE-XFEM), è stato sviluppato da Benvenuti [2] per lo studio di discontinuità sia di tipo forte che di tipo debole. Inizialmente, il modello è stato utilizzato per l’analisi di problemi piani di tensione relativi al calcestruzzo [3] e a materiali quasi-fragili [4, 5], mentre, recentemente, il modello è stato utilizzato per lo studio in campo lineare di problemi 3D relativi a interfacce planari e curve [6], e ad inclusioni [7]. Dal momento che le precedenti analisi 2D del modello RE-XFEM hanno dimostrato l’affidabilità e la robustezza del sopracitato algoritmo, nel presente lavoro una formulazione 3D non-lineare del modello, denominata 3D RE-XFEM, è stata implamentata in un codice parallelizzato FORTRAN [8] e applicata con successo a diversi problemi ingegneristici. La tesi raccoglie i risultati ottenuti dalla modellazione di diverse prove su travi in calcestruzzo e legno attraverso il modello 3D RE-XFEM. In particolare, gli argomenti trattati in questo lavoro possono essere divisi principalmente in due parti: • La prima parte è dedicata alla modellazione del distacco di rinforzi in FRP da provini in calcastruzzo. Il Cap. 2 introduce la formulazione dell’approccio 3D RE-XFEM nel caso di materiali quasi fragili, quali il calcestruzzo. Nel Cap. 3 vengono presentati i risultati ottenuti dalle simulazione del distacco dei rinforzi in FRP da blocchi di calcestruzzo, pubblicata in Ref. [9]. Il Cap. 4 è invece dedicato all’investigazione di travi rinforzate con FRP soggette a flessione, i cui risultati sono stati pubblicati in Ref. [10, 11]. • La seconda parte della tesi si focalizza sulla simulazione di strutture in legno. In particolare, nel Cap. 5 sono riportate alcune analisi, pubblicate in Ref. [12], effetuate mediante l’uso di un modello di danno ortotropo disponibile in letteratura, relative a travi di legno sottoposte ad un intervento di riabilitazione ad una delle estremità. Il Cap. 6 è dedicato allo sviluppo di un nuovo inedito modello costitutivo 2D che abbina ad un modello ortotropo elasto-plastico-danneggiante alla metodologia RE-XFEM per strutture in legno. Infine, nel Cap. 7 vengono raccolti e discussi gli aspetti significativi trattati nella tesi.

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14

Forti, Nadia Cazarim da Silva. "Analise numerica de vigas mistas em concreto e madeira." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257672.

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Orientador: Nilson Tadeu Mascia
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: O desenvolvimento tecnológico do projeto em estruturas de madeira permitiu melhorar o conhecimento de suas propriedades mecânicas e dos sistemas de conexões em estruturas. Estruturas mistas de madeira com concreto ou aço e os reforços do material com fibras de polímeros estruturais passaram a ser realidade. As estruturas mistas, constituídas por materiais de diferentes propriedades mecânicas associados, são uma solução alternativa às estruturas de uso corrente na construção civil. Essa medida busca obter redução de custos de construção, mantendo também a segurança estrutural, com um desempenho arquitetônico e ambiental vantajoso. A integração de uma estrutura mista deve-se, em geral, à eficiência do sistema de ligação, podendo ser do tipo rígido ou flexível. Esse sistema é responsável por transmitir a força de cisalhamento longitudinal na interface dos dois materiais combinados ao longo do comprimento da viga e também, impedir o desprendimento vertical dos mesmos. Esta pesquisa contribui para a análise do comportamento mecânico de vigas mistas de três maneiras: via programa de elementos finitos bidimensionais, via resolução analítica das equações de equilíbrio e via a equação do princípio dos trabalhos virtuais. A última abordagem foi concebida a partir de pesquisas de teoria das estruturas, expandindo seus conceitos para vigas mistas. A formulação proposta satisfaz as equações de equilíbrio mostrando-se consistente e seus resultados são condizentes com dados experimentais. Essa formulação pode ser facilmente integrada a códigos de elementos finitos requerendo apenas elementos unidimensionais
Abstract: The technologycal development of the design in wood structures has improved the knowledge of the material mechanical properties and the connection systems applied to structures. Composite structures of wood with concrete or steel and structural reinforcement using polymer fibers have become a reality. These structures, constituted by associating materials with different mechanical properties are an alternative solution for current using structures in civil construction. This arrangement aims at obtaining a reduction of construction costs also maintaing the structural safety with advantageous environmental and architectural performance. The integration of a composite structure is, in general, due to the efficiency of the connection system that can be rigid or flexible type. This system is responsible to transfer the longitudinal shear force on the interface of the associated materials along the beam length and to avoid the vertical detachment of them as well. This research contributes to the analysis of the mechanical performance of the composite beams in three ways: bidimensional finite element program, analytical solution of the equilibrium equations and virtual work principle equation via. The last approach was conceived from structural theory researches, expanding their concepts for composite beams. The proposal formulation fulfils the equilibrium equation showing to be consistent and the results fit with the experimental data. This formulation can be easily integrated to a finite element procedure requiring unidimensional elements only
Mestrado
Estruturas
Mestre em Engenharia Civil

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15

Plusa, Mariusz. "The influence of wooden fibres on chosen properties on normal contretes." Thesis, Halmstad University, School of Business and Engineering (SET), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1063.

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The purpose of work was to show properties of concrete modified with wooden fibres and to compare whem with unmodified concrete in order to show influence of these wooden fibres on chosen properties and to check if using of these types of admixtures is benificial in economical and technical point of view.

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Bennack, Valéria. "Análise da viabilidade técnica da reutilização da cinza de madeira em produtos cimentícios." Universidade do Estado de Santa Catarina, 2016. http://tede.udesc.br/handle/handle/1692.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Economic and environmental issues are directly related to industrial activities, and consume natural resources, generate waste that can overload the environment. This work aims to analyze the feasibility of waste reuse (wood ash) from the combustion of the timber industry in the manufacture of cement products in the construction process. In the first stage was carried out the characterization of the aggregates and further characterization of the residue by physical testing, chemical, mineralogical, Morphological, thermal and environmental. In the second stage, carried out in the laboratory the effects of the added substitution kid in concrete production by residues in 10% ratios and 20% were studied in consistency testing compressive strength, as well as the morphological difference was evaluated its structures for analysis of electron microscopy. In the final stage, held in specialized industry in manufacturing of cement artifacts were produced concrete interlocking blocks with replacement of fine aggregate by waste in the same proportions of testing with concrete. Comparative analysis of compressive strength and electron microscopy were also made at this stage. Results indicate the possibility of reusing waste (wood ash) in the manufacture of cementitious products.
As questões econômicas e ambientais estão diretamente relacionadas às atividades industriais que, além de consumir recursos naturais, geram resíduos que podem sobrecarregar o meio ambiente. Este trabalho tem como objetivo analisar a viabilidade do reaproveitamento de resíduo (cinza de madeira) proveniente do processo de combustão da indústria madeireira na fabricação de produtos cimentícios da construção civil. Na primeira fase foi realizada a caracterização dos agregados e na sequência a caracterização do resíduo através de ensaios físico, químico, mineralógico, morfológico, térmico e ambiental. Na segunda fase, realizada em laboratório, estudou-se os efeitos da substituição do agregado miúdo na produção de concreto pelos resíduos em proporções de 10% e 20% nos ensaios de consistência, de resistência à compressão, bem como foi avaliada a diferença morfológica de suas estruturas em análises de microscopia eletrônica. Na fase final, realizada em indústria especializada em confecção de artefatos de cimento, foram produzidos blocos intertravados de concreto com substituição do agregado miúdo pelos resíduos nas mesmas proporções dos ensaios realizados com concreto. Análises comparativas de resistência à compressão e microscopia eletrônica também foram realizadas nesta etapa. Resultados indicam a possibilidade de reutilização de resíduo (cinza de madeira) na fabricação de produtos cimentícios.

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Rich, David. "On-site application of self-compacting concrete (SCC)." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/17229.

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Self-Compacting Concrete (SCC) is a material which under its own self-weight flows to form and fill any shape, attains full compaction, without external energy input, to create a dense homogenous mass (based on Holton, 2003; The Concrete Society and BRE, 2005; Damtoft et al, 2008). It is, in respect to the history of concrete, a relatively new development, with its first UK application occurring in the late 1990s. Since then a significant amount of research has sought to understand its physical and structural properties, but there is a lack of a knowledge base on its practical application and performance in construction projects. Where it does exist, such research lacks robust and transparent data, particularly relating to the claimed attributes of the material (such as better surface finish, faster construction and lower overall costs). Using a combination of qualitative and quantitative research methods, this research investigates the construction practices employed when pouring SCC and presents new data on its practical applications. Interviews with a range of building contractors, ranging from multinationals to small UK businesses (SMEs), show that current perceptions of SCC limit its use to specific applications because practitioners see SCC as just another type of concrete . A critical examination of these attitudes led to the identification of three distinct scenarios for the use of SCC: 1. Reactive selection: in which a particular attribute of SCC provokes its use to solve a particular problem, often as a last minute substitution for conventional concrete the most common scenario. 2. Strategic change: in which the material is chosen on the basis of a balanced assessment of all its benefits and on the understanding that such benefits can only be attained if the contractor appreciates that there may be implications for the construction process a rarely experienced scenario. 3. Specification: in which there is complete acceptance of SCC as a method, not just as a material; a significant amount of early project involvement with knowledge holders, such as contractors and material suppliers, optimises the construction process. A rigorous work measurement study of live construction projects has made it possible to quantify the as-built costs of SCC for selected UK residential slab and multi-storey flat slab applications and compare this with the equivalent conventional concrete slab construction. On-site use of self-compacting concrete vi The results indicate that SCC can reduce construction times of structural topping layers of residential slabs by up to 73%, and has shown that SCC can also match, if not reduce, total as-built concrete placement costs in multi-storey applications. This new data will enable contractors, designers and specifiers to better understand the practical implications of using SCC for on-site applications, thereby leading to more potential instances of its early and planned specification, hence resulting in more of its full benefits being realised.

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Kennepohl, Stephan. "Delayed recognition memory for laterally-presented abstract and concrete words and drawings." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/MQ30911.pdf.

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19

Daerga, Per-Anders. "Some experimental fracture mechanics studies in mode I of concrete and wood." Licentiate thesis, Luleå tekniska universitet, Byggkonstruktion och -produktion, 1992. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18384.

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20

Jia, Daxin. "Ancient City Reservation." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/96713.

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The thesis started from the nostalgia for the historic district and the life within it. I don't agree with the radical method of reforming the historic district at the moment, which is rebuilding the whole district or demolishing it. I tried to find a new way to reform the historic district, so that the new project can blend into the habitats' lifestyle, in which way people can reconnect to their home land. During the design process, there is movie scenes, kungfu novels, and the living moment from my childhood came to my mind. And I translate those scenes into the spaces in the project through an architectural language.
Master of Architecture
I tried to find a new way to reform the historic district, so that the new project can blend into the habitats' lifestyle, in which way people can reconnect to their home land. During the design process, there is movie scenes, kungfu novels, and the living moment from my childhood came to my mind. And I translate those scenes into the spaces in the project through an architectural language.

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Carapelle, Claudia. "On the Satisfiability of Temporal Logics with Concrete Domains." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-190987.

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Temporal logics are a very popular family of logical languages, used to specify properties of abstracted systems. In the last few years, many extensions of temporal logics have been proposed, in order to address the need to express more than just abstract properties. In our work we study temporal logics extended by local constraints, which allow to express quantitative properties on data values from an arbitrary relational structure called the concrete domain. An example of concrete domain can be (Z, <, =), where the integers are considered as a relational structure over the binary order relation and the equality relation. Formulas of temporal logics with constraints are evaluated on data-words or data-trees, in which each node or position is labeled by a vector of data from the concrete domain. We call the constraints local because they can only compare values at a fixed distance inside such models. Several positive results regarding the satisfiability of LTL (linear temporal logic) with constraints over the integers have been established in the past years, while the corresponding results for branching time logics were only partial. In this work we prove that satisfiability of CTL* (computation tree logic) with constraints over the integers is decidable and also lift this result to ECTL*, a proper extension of CTL*. We also consider other classes of concrete domains, particularly ones that are \"tree-like\". We consider semi-linear orders, ordinal trees and trees of a fixed height, and prove decidability in this framework as well. At the same time we prove that our method cannot be applied in the case of the infinite binary tree or the infinitely branching infinite tree. We also look into extending the expressiveness of our logic adding non-local constraints, and find that this leads to undecidability of the satisfiability problem, even on very simple domains like (Z, <, =). We then find a way to restrict the power of the non-local constraints to regain decidability.

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POZZA, LUCA. "Ductility and behaviour factor of wood structural systems - Theoretical and experimental development of a high ductility wood-concrete shearwall system." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3422988.

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This dissertation focuses on the seismic behavior, ductility and dissipative capacity of modern timber buildings. A number of innovations in the field of timber structures are reported with special regard to the modeling techniques suitable for timber joints and to the characterization of the seismic behavior of modern timber systems. A preliminary overview on the seismic-resistant timber building technology and on their evolution from the past to nowadays is reported in the introduction of this thesis work. A review of the state of art about the available seismic codes is also reported and the main lack and incongruence with the current constructive practice are pointed out. The basic terms and concepts used in structural modeling and nonlinear analysis of timber structure are provided in the first part of this dissertation. The specific behavior of wood joints under cyclic actions and therefore under earthquakes is described with emphasis to the pinching effect and strength and stiffness degrading. A literature review on the main numerical models proposed to reproduce the hysteretic load-slip curve of single fasteners, joints and whole wooden elements is presented and discussed. A proposal for a new wood joint numerical model that can be easily implemented into a standard commercial Finite Element code is reported. The reliability of such new developed model to reproduce the fasteners hysteresis behavior is presented and critically discussed in comparison with experimental results. The second part of this thesis work is based on the evidence that the growing spread of the use of timber structures has led to the development of numerous innovative construction systems but at the same time a lack of code provisions for seismic timber structure still remains, in particular concerning the ductility (or behavior) factor q to be used for the design of different timber systems. This part of dissertation analyzes the definitions of the q-factor given in the scientific literature and its relevance in the design of seismic resistant structures. The traditional methods for estimating the q-factor are investigated and an innovative procedure for expeditious q-factor estimation is presented. The theoretical aspects of this new analytical-experimental procedure are reported and the main advantages and limitations are critically discussed. The seismic behavior of the Cross Laminated Timber structure is in deep studied in the third part of this dissertation. Such building system is largely spreading in the constructive practice but no design guidelines are provided in the seismic codes yet, especially for what concerning the definition of their sound behavior factor. Aim of this part of dissertation is to define the influence of some significant building characteristics, such as building technology, storeys number, slenderness, design criteria etc.., on the q-factor value. Such influences were studied referring to a numbers of building configuration and by means of nonlinear analyses carried out using specific hysteretic spring lamp-mass models. Based on such numerical assessment a proposal for an analytical formulation suitable to calculate the q-factor of CrossLam buildings has been developed and is presented. The validation and the applicability limits of the proposed formulation are presented and critically discussed. The final part of the dissertation investigates from the structural efficacy of newly developed construction technology which uses an external concrete shelter made of precast R.C. slabs to improve the performance of standard platform-frame shear walls. The idea consists of external plating made of thin reinforced concrete slabs screwed to the wooden frame of the walls. The concrete slab acts as a diaphragm against the horizontal forces. The structural response of this shearwalls under monotonic and cyclic loading conditions has been assessed by means of experimental tests. The tests outcomes are presented and compared with those from code provisions. Fulfillment of the requirements given by current codes as regards the attribution to the Higher Ductility Class is also verified. The influence of concrete skin on the seismic response of the shearwalls is also evaluated by means of numerical analysis and the assured “q” ductility factor is estimated.
In questo lavoro di tesi si analizzano il comportamento sismico, la duttilità e la capacità dissipativa dei moderni edifici con struttura di legno. Le principali innovazioni sviluppate in questa tesi di dottorato riguardano le tecniche di modellazione dei sistemi di connessione usati nelle strutture lignee e la caratterizzazione sismica dei moderni edifici in legno. L’introduzione della tesi evidenzia le caratteristiche che rendono le strutture in legno idonee per l’impiego in zona sismica e riporta una analisi storica delle principali tipologie di edifici sismo-resistenti a struttura in legno e la loro evoluzione dal passato ai giorni nostri. L’introduzione riporta inoltre un’analisi critica dello stato normativo Europeo ed Extraeuropeo sulle progettazione sismica degli edifici a struttura in legno evidenziando le principali lacune e incongruenze con la pratica costruttiva corrente. Il lavoro di tesi sviluppato affronta sostanzialmente quattro argomenti dettagliati in parti indipendenti. Le prime due sono di carattere generale e riguardano tutte le strutture in legno mentre le rimanenti sono specifiche di sistemi costruttivi innovativi e non ancora completamente caratterizzati sismicamente. La prima parte della tesi è dedicata alla descrizione del comportamento isteretico che caratterizza le connessioni utilizzate nelle strutture in legno e dei modelli numerici disponibili in letteratura per una riproduzione fedele di tale comportamento evidenziandone le potenzialità, i limiti di applicazione e l’efficienza numerica. Viene inoltre proposto un modello isteretico innovativo per riprodurre il comportamento delle connessioni tipicamente utilizzate nelle strutture in legno riproducibile anche mediante codici agli elementi finiti di tipo commerciale e non specificatamente orientati alla ricerca. Questa prima parte della tesi si conclude con la validazione e la descrizione dei principali vantaggi e limiti di applicazione della modello numerico proposto. La seconda parte della tesi riguarda la definizione del fattore di struttura q dei sistemi costruttivi in legno innovati e di recente diffusione che non sono annoverati nelle normative sismiche. In questa parte della tesi vengono descritti i metodi tradizionali utilizzati per la stima del fattore di struttura evidenziandone i vantaggi e i principali limiti. Viene proposta una procedura innovativa di tipo misto analitico-sperimentale che consente una valutazione speditiva del valore del fattore di comportamento q.. Questa parte del lavoro di tesi si conclude riportando la validazione della procedura proposta nonché gli aspetti teorici i limiti di applicabilità. La terza parte della tesi approfondisse lo studio sul sistema costruttivo a parete massiccia del tipo CrossLam. Preliminarmente viene riportatolo lo stato dell’arte sull’attività di ricerca sinora svolta su tale sistema costruttivo. L’obiettivo di questa parte del lavoro di tesi consiste nella definizione dell’effetto di determinate caratteristiche dell’edificio come il numero di piani, la snellezza, la composizione delle pareti, i criteri di progetto ecc. sul valore del fattore di struttura da utilizzare nella progettazione sismica dell’edificio stesso. Tale correlazione viene studiata mediante una serie di simulazioni numeriche su diverse configurazioni di edifici. I risultati ottenuti sono stati sintetizzati in una nuova formulazione analitica per la definizione del fattore di struttura q a partire dalle specifiche caratteristiche dell’edificio. Infine si riporta la validazione di tale formulazione analitica e si descrivono i principali vantaggi e limitazioni. L’ultima parte di questo lavoro di tesi consiste nello sviluppo teorico e sperimentale di un nuovo sistema costruttivo misto legno-calcestruzzo ad alta duttilità e performance anti-sismiche. Il sistema sviluppato consiste nell’applicazione di un rivestimento esterno in lastre di calcestruzzo alle tradizionali pareti di taglio a telaio. La riposta strutturale, la duttilità e il comportamento isteretico è stato verificato mediante dei test sperimentali condotti su differenti configurazioni di pareti. Infine sono state condotte delle simulazioni numeriche, con modelli numerici appositamente sviluppati e tarati sulla base dei test sperimentali, mediane le quali è stato possibile stimare il valore del fattore di struttura q da utilizzare per il progetto sismico di questo nuovo sistema costruttivo.

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Wonderlich, Sean M. "Strength of concrete masonry units with plastic bottle cores." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17389.

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Master of Science
Department of Architectural Engineering and Construction Science
Kimberly Waggle Kramer and Bill Zhang
Concrete masonry units are a common method of construction in the world. Since the masonry units can be constructed with ease. Fifty billion water bottles are consumed every year. Lack of waste management and recycling in third world countries has come to the attention of many organizations. The use of plastic bottles in construction materials has been around for the past twenty years, but with little focus on using full plastic bottles in the materials. The Engineers Without Borders student group on the campus at Kansas State University have found a way to utilize the full 500-mL plastic bottle in the creation of concrete walls. The bottles laid horizontally with concrete on both sides and as mortar between the bottles was used. These bottles create large voids in the wall decreasing the compressive strength of the wall. This thesis presents the results of a study conducted to determine the compressive strength of concrete masonry units with plastic bottle cores. The plastic bottles were used to create the center voids in the masonry units. Concrete was placed around the bottles to encase them in the masonry units. The study utilized 500-mL plastic bottles from five different water companies placed inside masonry units of 7.87-inch wide by 8.26-inch high by 15.75-inch long (200-mm wide by 210-mm high by 400-mm long) in size and analyzed the resultant compressive strength. The testing for compressive strength was determined according to the ASTM C140 standard. Results from this study were deemed reasonable due to the testing of concrete cylinders as a control compressive strength. Determination of the compressive strength of the concrete masonry units allows for further study to continue in concrete masonry units with plastic bottle cores to determine if they are viable in third world countries.

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Garth, John Stuart. "Experimental Investigation of Lateral Cyclic Behavior of Wood-Based Screen-Grid Insulated Concrete Form Walls." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1857.

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Insulated concrete forms (ICFs) are green building components that are primarily used for residential wall construction. Unlike most polystyrene based ICF variants, the Faswall ICFs used in these experiments were significantly denser because they were made from recycled wood particles and cement. The current design approach for structures constructed with this type of wall form only allows the designer to consider the contribution of the reinforced concrete cores. Previous research has shown that this approach may be conservative. This project experimentally evaluated the lateral structural response of these types of grid ICF walls under increasing amplitude of in-plane cyclic loading. Two different height-to-length (aspect) ratios (approximately 2:1 and 1:1) were investigated, as was the effect of simultaneous gravity load. Furthermore, the reinforced concrete grid was exposed for each aspect ratio in order to examine the contribution of the ICF blocks to the lateral response. Analyses of hysteretic behaviors and failure modes indicated conservatism in the current design approach for estimating lateral strength and ignoring the beneficial contribution of the ICF blocks to overall performance. The presence of the wall forms increased the lateral shear capacity of the walls by an average of 42% (compared to the walls with forms removed), while also increasing the deformation capacity by an average of 102%. Furthermore, by considering an additional gravity load of 10 kips-per-lineal-foot (klf), the shear resistance of the walls increased by 32% (versus walls only subjected to self-weight), on average, and the deformation capacity of the walls increased by an average of 19%. Comparisons of the experimental results to several design equations led to the recommendation of a design equation that was previously accepted for another type of ICF system.

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25

Delgado, Christina Michelle. "Inside + Outside." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33883.

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A study of public and private space through human scale architectural elements: Window, Material and Path. The project is an urban infill that is very narrow and long, and incorporates an alley that connects one side of the block to another. The program combines a small restaurant with a home above for the family that owns it. Questions of light and privacy immediately arise, and the thesis begins.

A window is typically a two dimensional object that opens for light and air. Window is a dining room overlooking a garden or a large sill to sit on. Window is not only part of the faÃ§ade but also breaks through it, bringing small private spaces beyond the building boundaries and defining the interior spaces of the home. Window is also a small skylight facing east, scooping in soft morning light to a bedroom. The materials of a building are what it is made of: its cladding, waterproofing, walls and floors. Material makes an emotive space through touch and reflection. Concrete is heavy, rough and protective, Concrete is boundary. Contrastingly, Wood is soft, flexible and changing, Wood is home.

An alley is a narrow walkway, an undesirable secondary access point. How can an alley become Path? Path is an invitation to walk and be, Path is not the same from beginning to end. Path belongs to the city, the restaurant, and the pedestrian.

Inside + Outside studies what makes these public and private places at the human scale, and how architecture appeals to intuition rather than definition.
Master of Architecture

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26

Bengtson, Anna. "Framing technological development in a concrete context : the use of wood in the Swedish construction industry /." Uppsala : Dept. of Business Studies (Företagsekonomiska institutionen), Univ, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3482.

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27

Johnson, Bryan Wacey. "A Wall a Bench a Tree." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/97515.

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A quest for agelessness in what we make seems to hold great allure. The spotless, the seamless, the immaterial, the idealized all labor in an attempt to escape the collection of dust and to transcend time, evincing neither origin nor decay. There is a rift between that manner of making which strives for an imperishable, ageless quality and the manner of making that embraces the poetics of material and temporality and mortality. It is beautiful to imagine the made thing that embodies a fable about welcoming inevitable change. From the moment it is made, it is gracefully, eloquently transforming; it willingly trades youth for handsome qualities that it did not first possess. It is commendable when a made thing achieves timelessness without striving vainly for agelessness. This thesis uses the vehicle of making an outdoor sitting room- composed of a wall, a bench, and a tree- to explore questions of the passage of seasons, of weathering, and of how the made thing can celebrate its own temporal nature.
Master of Architecture
There is a rift between that manner of making which strives for an imperishable, ageless quality and the manner of making that embraces the poetics of material and temporality and mortality. It is commendable when a made thing achieves timelessness without striving vainly for agelessness. This thesis uses the vehicle of making an outdoor sitting room- composed of a wall, a bench, and a tree- to explore questions of the passage of seasons, of weathering, and of how the made thing can celebrate its own temporal nature.

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28

Nautiyal, Divya. "Negotiating Boundaries - Exploring the Existential Experience of Architecture." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78259.

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Negotiating Boundaries is an effort to investigate and explore multisensorial environments. Throughout history, architecture is and has always been predominantly visual in nature. The visual dominance of architecture has often been critiqued by philosophers and architects. The thesis presents an argument that all senses " haptic, auditory, olfactory and vision, collectively contribute to experience a space. The thesis is a qualitative approach towards studying the significance of this existential experience of architecture in the built environment. The privilege of the sense of sight over the other senses and its bias in architecture cannot be neglected. Therefore, the experience of the visually impaired or blind has been used as a challenge to study these non-ocular centric spaces. Pallasmaa beautifully puts, Vision reveals what the touch already knows. We see the depth, the smoothness, the softness, the hardness of object; Cézanne even claimed that we see their odor. If the painter is to express the world, the arrangement of his colors must carry with this indivisible whole, or else his picture will only hint at things and will not give them in the imperious unity, the presence, the insurpassable plenitude which is for us the definition of the real. The live encounter with Frank Lloyd Wright Fallingwater weaves the surrounding forest, the volumes surfaces, textures and colors of the house, and even the smells of the forest and the sound of the river, into a uniquely full experience. The thesis presents a case to defend that architecture is not merely a series of visual scenes but has a fully embodied material and spiritual presence.4 Architects and Philosophers whose studies and explorations remain relevant to my interest are Juhani, Pallasmaa, Peter Zumthor, Louis Kahn, Steven Holl, and Carlo Scarpa amongst many others. Juhani Pallasmaa in his book, The Eyes of the Skin writes, "An Architectural work is not experienced as a series of isolated retinal pictures, but its fully integrated material, embodied and spiritual essence. It offers pleasurable shapes and surfaces molded for the touch of eye and other senses, but it also incorporates and integrates physical and mental structures, giving our existential experience a strengthened coherence and significance.
Master of Architecture

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29

Yu, Zhanjing. "Evaluation of underground supports made of wood and other materials." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/80152.

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A roof support system is one of the most important systems in underground mining. It may consist of various types of supports such as props, cribs, steel arches, powered supports and roof bolts, among others. In this research, powered supports and roof bolting are not included. Evaluation of underground supports needs to take account of several factors. These factors include the mechanical behavior of the supports, the interaction between the support and the surrounding strata, the cost of the support, and the overall economic results. In this research, emphasis is placed on the mechanical behavior of the supports. Criteria have been set up and, based on these criteria, a variety of supports have been evaluated.
Master of Science

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30

Oliveira, Daniele Gomes de. "Dissertação readymadenemtanto da aluna de poesia Rrosé Selavy Duchampignon (work in progress) - ideograma mental /." São Paulo : [s.n.], 2007. http://hdl.handle.net/11449/86988.

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Orientador: Omar Khouri
Resumo: Trabalho crítico-criativo sobre poesia visual. O elástico conceito de ideograma norteou este trabalho. Estrutura. Movimento. Seleção e crítica. Ordenação. Justaposição. de fragmentos. Redes de associações. Conexões. Processos e não produtos acabados. Crescimento sígnico. Universo diagramático. Método heurístico. Poesia e linguagem. O texto é um diagrama, icônico. Aprofundamento. Poesia Concreta. Criou-se a personagem Rrosé Selavy Duchampignon, que relaciona poesia e Duchamp. Síntese criativa. Recorte. Colagem. Montagem. Trabalho com apropriações. Nesta dissertação-livro-de-artista também são apresentados alguns trabalhos de poesia visual. E um termo de compromisso com a arte. Registrado em cartório.
Abstract: Critic-creative work about visual poetry. The elastic ideogram concept guided this work. Structure. Movement. Selection and criticism. O verplapping of fragments. Associantion networks. Connections. Processes and not finished products. Signic growth. Diagrammatic universe. Heuristic method. Poetry and language. The text is an iconic diagram. Deepening. Concrete poetry. The character Rrosé Selavy Duchampignon, relating poetry and Duchamp, was created. Creative synthesis. Cutting. Pasting. Assemblage. Work with appropriations. In this artist-book-dissertation some works of visual poetry are also presented. And an instrument of commitment whit the art. Notarized.
Mestre

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31

Aleksic, Uros. "Nynäshamn City Hall." Thesis, KTH, Arkitektur, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261376.

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Nynäshamn City Hall Nynäshamn is a small archipelago city south of Stockholm with around 15,000 inhabitants. Our task was to design a new City Hall that would represent an expansive and progressive community like Nynäshamn. The municipality has an explicit goal of approaching citizens and making them feel included. A building that represents a municipality where its political representatives work is a building that belongs to the citizens as much as it belongs to its employees. I entered the project by trying to find a way to integrate the public activities into activities that a closed state building has. The goal was to achieve a functioning entirety of two entirely different functions one building can have. The collaboration between these two functional extremes made it possible for large parts of the building to be available for visitors, which gave the City Hall an open character. The facade is intense. That's how I want to express inner life. The collision between two extremes forms an entirety. The centre of the building is an atrium that represents the people of Nynäshamn. It is the buildings largest public area. The atrium reaches out and penetrates through the facade of a state building and symbolically explains the character of the building.
Nynäshamn kommunhus Nynäshamn är en liten skärgårdstad söder om Stockholm med runt 15 000 invånare. Uppgiften gick ut på att tänka ut och gestalta ett nytt kommunhus som representerar en expansiv och framåtsträvande kommun som Nynäshamn. Kommunen har ett uttalat mål om att närma sig medborgarna. En byggnad som representerar en kommun var dess förtroende valda sitter är en byggnad som tillhör medborgarna lika mycket som den tillhör dess anställda. Utgångspunkten i projektet för mig var att integrera de offentliga funktionerna med funktionerna som en stängd statlig byggnad bär med sig. Målet var åstadkomma en fungerande helhet som präglar min byggnads fundament. Samarbetet mellan dessa två funktionella extremer tillgängliggjorde stora delar av byggnaden vilket gav kommunhuset en öppen karaktär. Fasaden är intensiv. Det är så jag vill utrycka inre livet. Kollisionen mellan två extremer bildar en helhet. Byggnadens kärna är ett atrium som representerar människor av Nynäshamn. Det är kommunhusets största offentliga yta. Atriet kragar ut och tränger sig genom fasaden av en statlig byggnad och på ett symboliskt berättar om husets karaktär.

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32

Ochoa, Antonio. "Poetics of presence : the work of Oliverio Girondo, Jorge Eduardo Eielson, and the Noigandres Group of Concrete Poetry." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/29303.

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At the end of the nineteenth century there emerged a set of poetic principles that considered the existence of the poem beyond verse, feet, the accepted set of poetic forms and most importantly considered that the poem did not only belong to the realm of temporal arts, but that also could have a presence in space. At the beginnings of the twentieth century Modernism and the avant-garde carried on these principles of innovation. But by the end of the 1930s these efforts seem to reach an end. In Latin America in particular poetry by that time seemed to become more interested in social and historical issues than in experimentation and innovation of forms. However, there were some poets who never abandoned their innovative spirit. It was in the 1950s that a second wave of artists looked back to the spirit of those innovators of Modernism and the historical avant-garde movements in order to reconnect with that tradition. They saw that in their efforts there was a lot more at stake than the simple search for new forms; there was a revolution in the conception of poetry. In their work they found new conceptions about the organisation of the work of literature that could be indicative of a new poetic reality, one where poetry was no longer constrained by time based structures. Those implications reverberated to the very roots of the existence of the work of literature. The works analysed and interpreted in this work belong to that second wave of innovative artists that searched for the extension of the poem out of the realm of temporality and into the domain of space. That is, they wanted to make the poem present in the world. This thesis discusses the work of Argentinean poet Oliverio Girondo, Peruvian poet and artist Jorge Eduardo Eielson, and the Brazilian Noigandres group of concrete poetry in relation to the issues and concepts of presence in their work. New ways of organising the work of literature prompted questions about its way of being. Traditionally the work of literature had been considered a temporal art but with the innovative conceptions of literature and art such consideration had to be put under question. It is not that literature had ceased to be a temporal art but that these authors integrated into their works spatial elements that transformed the way they are, and the way they are read. The works discussed in this thesis indicate their considerations about presence, the presence of the work of literature both as a concept within the works and as an issue to be addressed with the form of the work. This thesis shows the different forms in which these authors explored these issues. Their considerations about presence are ultimately a way to reconsider the 'place' and therefore presence of the work of literature in the simultaneously industrial and underdeveloped reality of Latin America in the second half of the twentieth century.

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33

Dawson, Paula Heatley Art College of Fine Arts UNSW. "The Concrete Holographic Image: an Examination of Spatial and Temporal Properties and their Application in a Religious Art Work." Awarded by:University of New South Wales. School of Art, 2000. http://handle.unsw.edu.au/1959.4/18201.

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The premise of this thesis is that the ???concrete holographic image???, a laser transmission hologram which has an object or a hologram of an object as its subject, has unique spatial and temporal properties which can suggest a plurality of tenses to a viewer. There is a lack of comprehensive analysis of the holographic representational system within art related theoretical and critical writing and a tendency to analyse individual works only in terms of generalities which apply to the concepts surrounding the holographic medium. While these form an important background for art image production, in some cases corresponding to artists works, the existing written material on the subject is inadequate as a model from which to draw the all important temporal conclusions. To date the critical reception of holograms has made no mention of acuity, the size of the viewing frustum, the depth of the image and scant mention of interference phenomena which are the intrinsic factors which I believe precipitate temporal illusions. Therefore this thesis examines the concrete holographic image in great detail on its own terms, firstly through theories of the basic image forming phenomena of interference and diffraction and secondly through the techniques of production as they have been adapted for the making of my art works. The extent of the metaphorical and allegorical potential of the spatial and temporal properties of the concrete holographic image are put to the ultimate test in a commission for St Brigid???s Church, Coogee. The Shrine of the Sacred Heart commission for St Brigid???s requires a concrete holographic image to facilitate devotion to the Sacred Heart. The Sacred Heart is not a physical thing but a complex, evolving spiritual entity with a realist pictorial history.

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34

Kazebee, Richard S. "Process of building: a school in suburbia." Thesis, Virginia Polytechnic Institute and State University, 1997. http://hdl.handle.net/10919/56207.

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Architecture lies in the synthesis of place, purpose and process. Place and purpose are of course important however the focus of this thesis is process. This thesis is an inquiry into the opportunities and limitations inherent in typical building processes. I wish to more fully know essential concerns of building, concerns such as spanning, laying, draining and protecting. I wish to know, the filigree of steel trusses, the order of a masonry wall, and the memory of concrete. Knowledge of building process reveals opportunities to raise building into architecture. For the following design a pallet of building processes were assumed from typical high school construction, including: The leveling of the site. The pouring of a concrete floor. The laying of block walls veneered in brick. The placement of steel trusses. The following project is an attempt at bringing these typical conditions of construction alive, at revealing their qualities and ultimately raising them into architecture.
Master of Architecture

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35

Owen, Timothy C. "Screen." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/33166.

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Two primary ideas drove the design of this church, sited at a Christian camping and retreat center in southwest Pennsylvania. The control of light entering the building is realized through a double layer of screens which form the exterior walls of the building and the walls of the sanctuary inside. These screens are the result of rigorous experimentation to maximize daylight and reduce glare in the space. The second main idea centers around the treatment of the overhead plane. Unified as a screen, curvilinear sheets of fabric are lit by openings in the roof to create sinuous bands of light that define the overhead plane and draw the eye upward. The primary design of these curves continue to define smaller elements in the church. As a secondary concern, the site links the church to the camp proper. A curving approach dips into the earth to obscure views of the church just until the visitor approaches the final court that leads to the building entrance. It is only when the person enters the sanctuary do they realize how the exterior and interior screens control the sunlight to illuminate a worship space that is flexible enough to both meet the needs of the camp and allow for future evolution of the liturgy.
Master of Architecture

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36

Timbré, Camilla. "Matematisk begreppsförståelse genom laborativt arbete i årskurs 4–6 : Begreppsförståelse som mål med laborativa material." Thesis, Högskolan Dalarna, Pedagogiskt arbete, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-25535.

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Den här systematiska litteraturstudien syftar till att undersöka vad forskning säger om att öka elever i årskurs 4–6 begreppsförståelse i matematik genom laborativa material och aktiviteter. Ett lärarperspektiv har antagits och studien behandlar olika faktorer som i de ingående ämnesdidaktiska artiklarna identifierats som betydelsebärande för den laborativa matematikundervisningen. Ett resultat indikerar att lärarens erfarenhet, didaktiska kunskaper och inställning till laborativa material har stor inverkan på hur materialen används i undervisningen och påverkar även elevernas möjligheter och syn på att lära sig matematik genom laborativa aktiviteter. Även olika perspektivs synsätt till att använda material i fast form i undervisningen tas upp, samt att det finns olika typer av konkreta, laborativa material. Begreppsförståelse är centralt för elevers förståelse av matematik och begreppsförmåga lyfts i Läroplanen 2011 för årskurs 4–6 fram som en av fem punkter som eleven ska få möjlighet att utveckla i olika sammanhang och situationer. Den övergripande frågan som denna systematiska litteraturstudie ämnat finna svar på är om och i så fall hur den laborativa matematiken med laborativa material kan vara ett sätt att arbeta på för att elever ska kunna nå en ökad förståelse för abstrakta begrepp.

Matematik

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37

Moreira, Fabiano Tofolli. "Análise da segurança e saúde do trabalho em empresas de pré-fabricado de concreto utilizando princípios da engenharia de resiliência." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/7459.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The Safety and Health at Work (SHW) management is recognized as one of the main factors so the enterprises may be able to fulfill their basic goals of coast, term and quality. One of the latest management strategies is the Resilience Engineering (RE) approach that considers the presence of four main principles for appliance: Top Management Commitment, Apprenticeship, Flexibility and Consciousness. Considering the intensive use of the concrete precast building systems it becomes substantial to study this section about the SHW aspects on the RE focus and record the good practices held by the companies. This work is based on the proposal elaborated by Costella (2008) which presents an Evaluation Method of the Safety and Health at Work based on the safety management principles and the RE. The case study method was adopted, a concrete precast producer enterprise was searched, which had a qualified management system, and it accepted to collaborate with the research. It was concluded that the researched Enterprise presents evidence of the application of the RE principles, mainly due to the existence of the SHW management. It was verified that there are ordinary and complementary concerns, such as the operation of critical sectors and the maintenance of the equipment currently used in factories and construction sites.
A gestão da Segurança e Saúde do Trabalho (SST) é reconhecida como um dos elementos essenciais para que os empreendimentos cumpram suas metas básicas de custo, prazo e qualidade. Uma das estratégias mais modernas de gestão é a abordagem da Engenharia de Resiliência (ER) que considera a presença de quatro princípios para aplicação: Comprometimento da Alta Direção, Aprendizagem, Flexibilidade e Consciência. Dado o uso intensivo dos sistemas construtivos pré-fabricados de concreto torna-se importante estudar este setor sobre os aspectos de SST sobre o enfoque da ER e registrar as boas práticas realizadas pelas empresas. Este trabalho se baseia na proposta elaborada por Costella (2008) que apresenta um Método de Avaliação da Segurança e Saúde do Trabalho, com base nos princípios de gestão da segurança e da ER. Foi adotado o método de estudo de caso e pesquisada uma empresa fabricante do setor de pré-fabricados de concreto que se prontificou a colaborar com a pesquisa e possuía sistema de gestão de qualidade certificado. Concluiu-se que a Empresa pesquisada apresenta indícios de aplicação dos princípios da ER, devido principalmente ao fato de haver a gestão da SST. Verificou-se que existem preocupações em comuns e complementares, como a operação de setores críticos e a manutenção dos equipamentos em uso nas fábricas e canteiros. Palavras chave: Construção Civil. Segurança e Saúde do Trabalho. Engenharia de Resiliência.

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38

Labò, Simone. "Holistic sustainable renovation of Post-World War II reinforced concrete building under a life cycle perspective by means diagrid exoskeletons." Doctoral thesis, Università degli studi di Bergamo, 2019. http://hdl.handle.net/10446/128920.

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Enormous resources are being invested in Europe to foster environmental, economic, and social sustainability; however, such relevant effort to reach ambitious targets may be a missed chance, unless a deep and systematic intervention on the built environment is undertaken targeting sustainability, safety and resilience at the same time. This thesis provide a contribution to the scientific debate, focusing on holistic renovation from outside of reinforced concrete building by embracing a life cycle perspective. Effectiveness of such an approach to the renovation with respect to traditional retrofit actions emerges both in the construction time when addressign the barriers to the renovation such as the inhabitant relocation and the existing buildgin disruption, and when broadening the time frame of the analyses, shifting from the construction time to a life cycle perspective. In this second case, the potential of the holistic approach becomes clear in reducing costs, impacts on the inhabitants and impacts on the environment over the building life cycle. The reults of this new approach is a retrofit solution based on a Life Cycle Thinking, which not only entails the use of recyclable/reusable materials, but also encourages interventions carried out from the outside the buildings, and imply the adoption of reparable, easy maintainable, adaptable and fully demountable solutions with pre-fabricated components, thus guaranteeing, at the end-of-life, the selective dismantling and reuse or recycle of the components to reduce construction waste. The described solutions, which couples structural retrofit in the renovation action, stem as an enhancement of past pioneering “camouflage” interventions, such as double-skin solutions entailing in many benefits such as the protection of human lives, resilience and the lengthening of the existing buildings service life, the repairing costs and building downtime reduction, reduction of the environmental impact associated with seismic risk over the building life cycle and long-term protection of the investment (Marini et al. 2018). Within such a new perspective, new technology options are needed to innovatively combine structural retrofit, architectural restyling and energy efficiency measures; in this work an effective retrofit solution is proposed. Among the possible retrofit solutions the diagrid structures as innovative strenghening technique from outside are investigated. In the first part of this thesis, the state of the art of diagrid design is reported. New criteria for the design of retrofit solution are set, and a design procedure for elastic diagrid is proposed. In the third chapter, a parametric evaluation of the retrofitted system through a simplified 2 DOF system is conducted, and a set of design spectra are defined in order to simplify the design procedure and derive the optimal retrofit parameter for RC buildings. Finally, a reference case study representative of the typical RC building is developed in the fifth chapter of this work to asses and validate the procedure.

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39

Jafarian, Mostafa. "Behaviour of reverse channel connection to concrete filled hollow tube columns under fire conditions." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/behaviour-of-reverse-channel-connection-to-concrete-filled-hollow-tube-columns-under-fire-conditions(f60a80b2-a053-49d7-bbaf-22de4291a8e3).html.

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This thesis presents the results of a research project to investigate the behaviour of the two components of a reverse channel connection to concrete filled tubular sections: the reverse channel and the steel tubular section, at both ambient and elevated temperatures. This research forms part of a European Union funded project on the robustness of joints to composite columns under fire conditions. The specific objectives of this research are to develop methods of quantifying the load-deformation behaviour at various temperatures of the two components. This research has been carried out through a combination of experiments, numerical simulations and analytical developments. Two series of tests have been carried out at different elevated temperatures, one for the reverse channels with lateral loads to the web applied as tensile loads through bolts and one for the concrete filled tubular sections under lateral loads applied through two steel plates (simulating the legs of a reverse channel) in the longitudinal direction of the section. These tests have been used to provide data for the validation of the numerical models based on using the general finite element package ABAQUS. The validated numerical models have been used to conduct a number of parametric studies to provide extensive data for the development of analytical methods to determine the load-deflection characteristics of the two components. For the reverse channel web, the load-deflection relationship consists of two parts and this research has developed analytical equations to predict initial stiffness, yield and ultimate resistance. The initial stiffness is based on extending and simplifying the Timoshenko solution for a plate under a block of lateral loads. The yield resistance is based on the yield line solution that the failure patterns were chosen based on the results attained from test and simulations. The ultimate resistance was calculated based on virtual work principle for the patterns considered in the yield resistance part. For the rectangular concrete filled tubular sections under lateral pulling forces applied through two plates, the load-deflection curve consists of two parts, depicting a linear phase followed by a nonlinear part. This research has developed expressions to calculate initial stiffness, yield resistance, and ultimate resistance. The initial stiffness is formulated according to the Timoshenko solution for a partially loaded plate. The yield resistance is determined by employing yield line solution for the yield patterns obtained from both the test and FE modelling. The ultimate resistance is evaluated by implementing the virtual work principle to the patterns considered in former part. The analytical load-deflection solutions have been compared with the numerical simulation and the experimental results and the agreement is generally satisfactory.

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40

Glimbeck, johan, and Olle Ingemarsson. "Steel vs Composite, Heavy vs light : Sustainability in construction - a case study investigating two concrete form work systems uning a MCDMmethod." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-41356.

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This Bachelor thesisis a comparison of two different concrete forms viewed from a sustainable perspective by using a Multi Criteria Decision Making(MCDM)method. Sustainability is a broad concept, often degraded in threepartswhich are financial-,environmental-and socialsustainability. This Bachelor thesisstrives to determine what sustainability is when it comes to monolithic concrete casting in Sweden. In this Bachelor thesissustainabilityhas been degraded in threeparts, financial-,environmental-and work environmental sustainability.Although,the two different forms fill the same function, they differ in many areas. The first one, TRIO,is made of steel and plywoodand is heavy, loud, with a big area and in need of a crane to be able toassemblethe form. The second one, DUO,is made from the composite materialPolytech and isalmost soundless, with a smaller area and lightweight tobe able to be used without crane. The purpose of the MCDM-methodis to create a tool with the purpose of facilitating the choice of concrete forms for monolithic casting while taking sustainability into account. The tool is to ease the decision in building production for both the contractor and for designers. The Bachelor thesisis a case study with both qualitative and quantitative methods.To make a fair comparison between the two forms in this Bachelor thesis,a fictitious project is created toevaluate different criteria for sustainability in design and production. This is doneunder the same premises to be able to obtain an equivalent result.In the fictitious project it turned out that TRIO was the best choice from work environment and economic sustainability, from environmental sustainability it turned out that DUO was the best. Furthermore, it has been difficult to obtain full validity in the MCDM method, all criteria have not been fulfilled inthe environmental field. The environmental area has been the most difficult to investigate and to obtain relevant data in.MCDM has good opportunities to provide great benefit if there were more standardized data to put into it. In this work, very much work was done for a small result.

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Colorado, Urrea Gabriel J. "Service Life of Concrete and Metal Culverts Located in Ohio Department of Transportation Districts 9 and 10." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1408279810.

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Oliveira, Daniele Gomes de [UNESP]. "Dissertação readymadenemtanto da aluna de poesia Rrosé Selavy Duchampignon (work in progress) -: ideograma mental." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/86988.

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Made available in DSpace on 2014-06-11T19:22:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2007Bitstream added on 2014-06-13T19:08:02Z : No. of bitstreams: 1 oliveira_dg_me_ia.pdf: 962417 bytes, checksum: 517fb2982a917fb012d217514abff806 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Trabalho crítico-criativo sobre poesia visual. O elástico conceito de ideograma norteou este trabalho. Estrutura. Movimento. Seleção e crítica. Ordenação. Justaposição. de fragmentos. Redes de associações. Conexões. Processos e não produtos acabados. Crescimento sígnico. Universo diagramático. Método heurístico. Poesia e linguagem. O texto é um diagrama, icônico. Aprofundamento. Poesia Concreta. Criou-se a personagem Rrosé Selavy Duchampignon, que relaciona poesia e Duchamp. Síntese criativa. Recorte. Colagem. Montagem. Trabalho com apropriações. Nesta dissertação-livro-de-artista também são apresentados alguns trabalhos de poesia visual. E um termo de compromisso com a arte. Registrado em cartório.
Critic-creative work about visual poetry. The elastic ideogram concept guided this work. Structure. Movement. Selection and criticism. O verplapping of fragments. Associantion networks. Connections. Processes and not finished products. Signic growth. Diagrammatic universe. Heuristic method. Poetry and language. The text is an iconic diagram. Deepening. Concrete poetry. The character Rrosé Selavy Duchampignon, relating poetry and Duchamp, was created. Creative synthesis. Cutting. Pasting. Assemblage. Work with appropriations. In this artist-book-dissertation some works of visual poetry are also presented. And an instrument of commitment whit the art. Notarized.

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Pessôa, José Renato de Castro. "Análise numérico-experimental de estruturas de concreto com utilização da energia de fraturamento." Universidade do Estado do Rio de Janeiro, 2007. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=780.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A evolução dos concretos utilizados nas últimas décadas deu origem ao Concreto de Alto Desempenho (CAD), que tem, entre suas características, alta resistência à compressão e baixa permeabilidade. Com o desenvolvimento dos produtos químicos utilizados na construção civil, em especial os superplastificantes e superfluidificantes, a utilização desse tipo de concreto tornou-se cada vez mais freqüente pela possibilidade de se obter uma mistura suficientemente trabalhável utilizando-se fatores água/cimento menores do que 0,35. Devido à sua microestrutura mais homogênea, esse tipo de concreto apresenta um comportamento mais frágil do que os concretos convencionais, exigindo uma melhor caracterização do material. A partir do final da década de 70 começou-se a aplicar os conceitos da Mecânica da Fratura para análise do comportamento de estruturas construídas com esse tipo de concreto. Como em algumas situações a resistência nominal de peças de concreto diminui com o aumento de suas dimensões, houve a necessidade de se considerar o efeito de escala das estruturas a fim de se obter níveis de segurança mais adequados no seu dimensionamento, o que justificou a utilização da Mecânica da Fratura. Neste trabalho a energia de fraturamento foi obtida experimentalmente pelo método do trabalho de fraturamento e pelo método do efeito de escala, por meio de ensaios estáveis de flexão de três pontos em amostras de concreto de alto desempenho com entalhe. Foi também desenvolvida a simulação numérica de uma viga com entalhe, analisada pelo método dos elementos finitos e empregando-se na modelagem constitutiva os conceitos da Mecânica da Fratura aplicada ao concreto. As vigas foram moldadas e ensaiadas no Instituto Politécnico do Rio de Janeiro (IPRJ) da Universidade do Estado do Rio de Janeiro (UERJ) na cidade de Nova Friburgo. Os ensaios foram realizados com controle de deslocamento da célula de carga. Foram ensaiadas três séries de 12 vigas, com quatro dimensões diferentes, geometricamente proporcionais, e três amostras para cada dimensão, totalizando 36 vigas. As alturas utilizadas para as vigas foram 38, 76, 152 e 304 mm, e sua espessura foi mantida constante igual a 38 mm. Os corpos de prova cilíndricos, para caracterização da resistência à compressão do concreto, foram moldados no IPRJ e rompidos no laboratório de engenharia civil da UERJ, na cidade do Rio de Janeiro. Os concretos utilizados apresentaram resistência à compressão média de 70 MPa.
The evolution of the concrete mixes used during the last decades gave birth to the High Performance Concrete (HPC), which, among its main characteristics, presents high strength and low permeability. With the development of chemical products used in civil engineering constructions, mainly the superplasticizers, the use of this kind of concrete has become more and more frequent due to the possibility of obtaining a workable mixture with a water/cement ratio lower than 0.35. Due to its more homogeneous microstructure, the HPC presents a more fragile behavior than the conventional concrete, demanding a better characterization of the material. At the end of the 1970s, concepts of the Fracture Mechanics started to be used for the analysis of the structural behavior of concrete structures. As the nominal stress of the material decreases as the size of the structure increases, it became necessary to consider this size effect in the analysis in order to obtain more suitable levels of security. This fact justifies the use of the Fracture Mechanics in the structural analysis of concrete structures. In this work, the fracture energy was experimentally obtained using the work-offracture method and the size effect method by performing three-point bend tests in HPC notched beams. It was also developed a numerical simulation of the tests, performing the analysis through the Finite Element Method and applying the concepts of the Fracture Mechanics of Concrete into the constitutive model. The notched beams were molded and tested at the Polytechnic Institute of the State University of Rio de Janeiro (IPRJ/UERJ), located in the city of Nova Friburgo. The tests were controlled by the vertical displacement of the load cell. Three series of twelve beams with four geometrically similar sizes were tested. Three samples for each size were cast, making an amount of 36 beams. The beams were 38, 76, 152 and 304 millimeters high and the width was kept constant equal to 38 millimeters. To characterize the concrete compression strength, 100x200 millimeters cylinders were molded at the IPRJ and tested at the UERJ civil engineering laboratory in the city of Rio de Janeiro. The tested concretes presented a medium compressive strength of 70 MPa.

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Chardonnet, Lucile. "A Shared Learning Space inMidsommarkransen." Thesis, KTH, Arkitektur, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223240.

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New school buildings are met with questions in growing cities like Stockholm: How to place them? Which scale? What use, degree of openness, and flexibility, and for whom? This reflection has been made in relation to a suburban area, resulting in a proposal for smaller schools supported by another, shared, building that welcomes more specific activities and is open to the public. It would offer more specialized and adapted spaces to cooking, sewing, music and dance classes, as well as a bigger library and would intensify their use.

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Bystedt, Gabriella, and Bernuy Fatima Estrada. "Balance between financial and quality gains in housing production : A study on concrete and wooden frames." Thesis, KTH, Byggteknik och design, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296546.

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With increased demand for housing in Sweden's metropolitan regions, it is of greatimportance to meet the need and build more. The supply of housing is governed byaccess to land and what it costs to build apartment houses. In Sweden, there is ahistory of cartel formation of contractors and at the turn of the millennium, thegovernment invested funds to create increased price transparency in theconstruction sector. Based on this, the purpose of this project is to investigate how itis possible to today produce housing more economically, while maintaining quality.The study is limited to the purchase of prefabricated hollow core and load-bearingwall elements in both concrete and wood. The goal is to be able to compare prices ofthese construction parts between Swedish and foreign suppliers. The foreignsuppliers are limited to the ones operating in the Baltic countries and Poland. Thus, itmust be investigated which of the wooden or concrete frames is most economicallyprofitable, what opportunities there are with international purchases of frameelements and what should be taken into account in international purchases.
I och med ökad efterfrågan på bostäder i Sveriges storstadsregioner är det av vikt atti samma takt öka utbudet. Utbudet styrs av tillgång till mark samt vad det kostar attbygga. I Sverige finns en historia av kartellbildning av byggföretag och regeringensatte vid millennieskiftet in medel för att skapa ökad pristransparens inombyggsektorn. Med bakgrund i detta är syftet med examensarbetet att undersöka hurdet idag går att producera bostäder mer ekonomiskt, med bibehållen kvalitet iåtanke. Studien avgränsas till inköp av prefabricerade håldäck och bärandeväggelement i betong respektive trä. Målet är att kunna jämföra priser av dessakonstruktionsdelar mellan svenska och utländska leverantörer. De utländskaleverantörerna avgränsas till att verka inom baltikum och Polen. Således ska detutredas vad utav trä- eller betongstomme som är mest ekonomiskt lönsamt, vilkamöjligheter som finns med internationella inköp av stomelement samt vad som börtas hänsyn till vid internationella inköp.De risker som finns kopplade till just internationella inköp är bland andra risk attprodukten inte stämmer överens med vad som avtalats och leveransförseningar.Logistikrisker begränsas med hjälp av avtal reglerade utifrån det internationellaregelverket Incoterms. Det finns även politiska och valutarelaterade risker medinternationell handel.ISO 9000 är ett kvalitetsledningssystem som ligger till grund för att företag ochorganisationer ska kunna säkerställa att kvaliteten i deras arbete svarar upp motkundens behov och krav. ISO 14000 samlar standarder inom miljöledningssystem.Intervjuer av sex svenska och fem utländska leverantörer om pris och kvalitetsarbetegav intressanta resultat för studien. Samtliga utländska leverantörer är certifierademed ISO 9001 samt ISO 14001. Två av sex svenska bolag har ISO9001-certifieringen och hälften ISO 14001-certifieringen. Att köpa prefabriceradebetongelement är enligt studien inte ekonomiskt lönsammare i utlandet, det är detdäremot att köpa träelement.

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South, Andrew J. "Unintended Social and Economic Consequences Resulting from the Implementation of New Construction Technologies in the Developing World." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2807.

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One of the key components of international development is to provide adequate shelter for citizens of developing countries. This is often accomplished by governmental, non- governmental, and private organizations that seek to lower the cost, increase the quality, and expand the availability of safe, sustainable housing through the use of innovative technologies. These new technologies can affect the social and/or economic structure within communities. This paper is a case study resulting from the construction of a seventy-one-home village, including infrastructure, near Yogyakarta, Indonesia by a foreign, aid-based non-governmental organization (NGO). The village was relocated less than two kilometers from its original site after a massive landslide, triggered by the 2006 earthquakes of Central Java, virtually destroyed the entire community. Four years after construction the researcher took an inductive inquiry approach through interviews with residents of the community and residents of neighboring communities to understand the social and economic impacts. The research project explored the unintended consequences to the community resulting from the NGO's use of innovative housing technologies (steel reinforced concrete domes and planned community development) without a thorough understanding of underlying community culture and interactions.

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Aljija, Elnes. "Jämförelse Mellan Lätt och Tung Stomme på ett Kontorshus." Thesis, Linnéuniversitetet, Institutionen för teknik, TEK, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19176.

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I början av varje nytt projekt stöter man på de olika alternativ av stomme- och bjälklagskonstruktioner som finns att välja mellan, och frågan blir ofta vilken alternativ som är optimal för den aktuella projekteten. Den optimala lösningen för varje projekt existerar inte, på grund av de olika faktorer och förutsättningar som styr projektet, till exempel: ekonomi, typ av byggnad, terrängtyp etc. Frågeställningen i denna rapport är om limträ eller betong är den mest optimala alternativen som stommaterial i det aktuella projektet. Jämförelsearbetet utgående från förutsättningar har gjorts genom att dimensionera delar av ett projekt med både materialen. Fokus har lagts på skillnader i byggnadshöjd, vindstabilitet och grundläggningen. Resultaten tyder på om man ska bygga ett kontorshus eller flervåningshus vore betong mer lämpligare alternativ jämfört med limträ. Skillnaden i byggnadshöjd finns men är förvånansvärt inte så stor mellan de två olika stommaterial. Dock skillnaden varierar avsevärd när det gäller bjälklagshöjd mellan limträ och betong. Detta pga krav på nedböjning och svikt som ställs på limträbjälklag. Båda stommaterial klara vindstabiliteten utan plintar, som är ganska intressant speciellt med tanke på limträets låga vikt. När det gäller grundläggningen, blev skillnaden betydlig större mellan limträ och betong. Dimensionering enligt Eurokoder har gjorts genom egna handberäkningar och även användandet av programvaran Strusoft.
At the beginning of each new project comes across on the different options of frame and floor construction available to choose from, and the question is often which option that is optimal for the current project. The optimal solution for each project does not exist, because of the different factors and conditions that govern the project, such as: economy, building type, terrain type, etc. The issue addressed in this report is on glue-laminated wood or concrete is the most ideal alternative to framing materials in the current project. Comparative work on the basis of preconditions has been made by dimensioning the parts of a project with both materials. The focus was on differences in building height, wind stability and the foundation. The results indicate if you're going to build an office building or apartment building,concrete is more appropriate alternative compared to the glue-laminated wood. The difference in building height is surprisingly not so great between the two different frames. However, the difference varies considerably in terms of floor height between glue-laminated wood and concrete. This is due to requirements for deflection and springines imposed on wood. Both frames can handle wind stability without plinths, which is quite interesting especially in view of the wood's light weight. Regarding the foundation, the difference was significantly greater between glue-laminated wood and concrete. The design according to Eurocodes has been made by hand calculations and also the use of the software Strusofts.

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Linhares, Bruno Tasca de. "Análise de pontes em estruturas mistas de aço-concreto de seção caixão com protensão externa." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/118891.

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Estruturas Mistas de Aço-Concreto têm sido usadas extensivamente na construção de pontes e viadutos urbanos, especialmente a partir da segunda metade do século XX. A popularidade desse tipo de solução, com seções caixão, cresceu devido a sua alta capacidade à flexão, rigidez à torção e uma seção transversal fechada que reduz a superfície exposta a corrosão. Este trabalho discorre sobre o comportamento estrutural, procedimentos de análise e verificação em Estado Limite Último (ELU) de pontes mistas de seção caixão com aplicação de protensão externa. Em vista da escassez de literatura sobre o assunto e inexistência de norma brasileira, o trabalho objetiva produzir um roteiro de análise para a determinação da capacidade à flexão em ELU de estruturas mistas de seção caixão protendidas. Embasado na norma americana AASHTO-LRFD:2012 e na revisão bibliográfica, propôs-se um estudo de caso para verificação/dimensionamento analíticos da estrutura, tratando de Momentos Fletores Resistentes (positivos e negativos), Esforço Cortante Resistente e conectores de cisalhamento. Após esta etapa inicial, aplicou-se protensão à estrutura e, por meio de métodos analíticos, e auxílio do método dos trabalhos virtuais, obtiveram-se as perdas de protensão e a relação entre a deformação adicional do cabo de protensão em função do momento externo aplicado à estrutura. Deste modo pôde-se fazer o equilíbrio de forças horizontais, através do método da Bissecção, e obter-se o valor de incremento de Momentos Fletores Positivos e Negativos Resistentes da estrutura. Observou-se, com a protensão, um aumento de resistência importante na região de Momentos Fletores Negativos em ELU (~40%); para a região de flexão positiva esse incremento foi pouco superior a 7%, em relação à estrutura nãoprotendida. Por fim, modelou-se a estrutura em elementos finitos de casca com o software SAP2000, a fim de confrontar a análise inicial, feita em modelo de barras de pórtico espacial, preconizada pela norma AASHTO-LRFD:2012. Os resultados mostram que o modelo em barras de pórtico espacial, em termos de deslocamentos e tensões, é adequado à análise deste tipo de estrutura.
Steel-Concrete Composite Strutures have been used extensively in the construction of bridges and urban viaducts, especially from the second half of the twentieth century. The popularity of this type of solution, with box sections, has increased due to its high flexural capacity and torsion stiffness combined with a closed cross section that reduces the exposed surface to corrosion. This paper discusses the structural behavior, analysis and verification procedures in the Ultimate Limite State (ULS) of Composite Box Girder Bridges with application of external prestressing. In view of the paucity of literature on the subject and the absence of Brazilian standard, this work aims to produce a analysis script to determine the flexural capacity of prestressed composite box girder structures in ULS. Grounded in the American Standard AASHTO-LRFD:2012 and the literature review, we propose a case study for analytical verification/dimensioning of the structure, concerning positive and negative bending moments, shear and shear connectors. After this initial stage, prestressing was applied to the structure, and with de aid of analytical methods, and the virtual work method, the prestress losses and the relation between the additional strain of the tendons and the external applied moment were obtained. Thus, it was possible to make the horizontal forces balance through the Bisection Method and obtain the increment of positive and negative flexion strength. It was observed, with prestressing, an important increase of capacity in the negative bending region for ULS (~40%); for the positive bending region, the increase was somewhat higher than 7%, compared with the non-prestressed structure. Finally, a finite element model with shell elements was held with aid of the software SAP2000 to confront the initial analysis, made in space frame bars model, recommended by AASHTO-LRFD:2012 standard. The results show that the space frame bars model, in terms of displacements and stresses, is appropriate to analyze this type of structure.

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Walubita, Lubinda F. "Comparison of fatigue analysis approaches for predicting fatigue lives of hot-mix asphalt concrete (HMAC) mixtures." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/3898.

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Hot-mix asphalt concrete (HMAC) mixture fatigue characterization constitutes a fundamental component of HMAC pavement structural design and analysis to ensure adequate field fatigue performance. HMAC is a heterogeneous complex composite material of air, binder, and aggregate that behaves in a non-linear elasto-viscoplastic manner, exhibits anisotropic behavior, ages with time, and heals during traffic loading rest periods and changing environmental conditions. Comprehensive HMAC mixture fatigue analysis approaches that take into account this complex nature of HMAC are thus needed to ensure adequate field fatigue performance. In this study, four fatigue analysis approaches; the mechanistic empirical (ME), the calibrated mechanistic with (CMSE) and without (CM) surface energy measurements, and the proposed NCHRP 1-37A 2002 Pavement Design Guide (MEPDG) were comparatively evaluated and utilized to characterize the fatigue resistance of two Texas HMAC mixtures in the laboratory, including investigating the effects of binder oxidative aging. Although the results were comparable, the CMSE/CM approaches exhibited greater flexibility and potential to discretely account for most of the fundamental material properties (including fracture, aging, healing, visco-elasticity, and anisotropy) that affect HMAC pavement fatigue performance. Compared to the other approaches, which are mechanistic-empirically based, the CMSE/CM approaches are based on the fundamental concepts of continuum micromechanics and energy theory.

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Bezerra, Larissa Marinho Coelho de Medeiros. "Planejamento e controle da produção com a utilização de células de trabalho: estudo de caso em construções com vedações verticais em concreto armado moldadas in loco." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18141/tde-05012011-154700/.

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A indústria da construção civil vem assumindo um papel determinante no desenvolvimento econômico do país e vivenciado um crescimento exponencial que exige das empresas uma dedicação crescente na busca por novas tecnologias construtivas e ferramentas que auxiliem na gestão de empreendimentos. Sistemas construtivos racionalizados que repercutam na melhoria dos produtos com a redução de custos são essenciais para manter a competitividade no setor. O sistema construtivo de vedações verticais em concreto armado moldadas in loco confere uma alternativa na produção de habitações em larga escala caracterizada pela redução de custos e alta produtividade originando uma cadeia produtiva que auxilia no planejamento e controle da produção em obras. O presente trabalho tem como objetivo contribuir para o planejamento e o controle da produção de edificações que utilizam em seu processo o sistema construtivo anteriormente citado, propondo um modelo de organização da produção baseado na redução da variabilidade dos processos produtivos por meio do fluxo contínuo da produção, que proporcione o trabalho ininterrupto no canteiro de obras. A proposta associa os princípios que sustentam a filosofia produtiva da Lean Constrution, e recomenda um modelo para o planejamento operacional de curto prazo, que defina os fluxos produtivos pela aplicação de ritmos constantes nas atividades mediante o nivelamento dos recursos de mão-de-obra envolvidos no processo produtivo com a introdução de células produtivas que proporcionam lotes otimizados de trabalho, constituindo células de trabalho.
The construction industry has a decisive role in economic development of the country and experienced exponential growth requires dedication growing companies in the search for constructive new technologies and tools that will assist them in managing exposures. Constructive rationalized systems that reverberate in improvement of products with reducing costs is critical to remain competitive in the industry. The constructive system using cast-in-place concrete vertical panels confers an alternative in the production of large-scale housing characterized by reduced costs and high productivity that provides a productive chain which assists in the planning and production control in workplaces. This work aims to contribute to the planning and production control buildings that use its constructive system previously cited, proposing a model organization of production based on reducing variability in productive processes through streaming production, providing uninterrupted work on site. The proposal combines the principles supporting the production philosophy of Lean Constrution, and recommends a template for the short-term operational planning, defining workflows by applying patterns appearing in activities by the leveling of labour resources involved in the production process with the introduction of work cells that provide small batches of work.

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Dissertations / Theses on the topic 'Concrete word'

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