As estruturas de madeira composta com alma em compensado já vem sendo amplamente utilizadas em diversos países onde as estruturas de madeira estão tecnologicamente mais desenvolvidas, oferecendo aos engenheiros civis mais uma opção de sistema construtivo eficiente, seguro e duradouro. Nesse trabalho são apresentados estudos teóricos e experimentais referentes às estruturas de madeira compostas utilizando compensado nas almas, e em especial as estruturas cuja ligação alma mesa é feita por pinos metálicos. O objetivo desse trabalho é desenvolver critérios de dimensionamento dessas estruturas para serem aplicados no Brasil. Vários critérios de dimensionamento de elementos compostos foram encontrados na bibliografia, alguns com simplificações que desconsideram efeitos de composição parcial e outros mais completos, que consideram deformações por cisalhamento, composição parcial etc. Com os resultados dos ensaios de vigas compostas pregadas foi possível comparar valores experimentais com resultados teóricos, concluiu-se que os critérios de dimensionamento do EUROCODE 5 são adequados. Os ensaios de rigidez de nó de pórtico de seção composta permitiram o desenvolvimento de metodologia para o cálculo da rigidez dessas ligações, visto que não existe formulação equivalente na bibliografia internacional. Concluiu-se que as ligações por pinos metálicos apresentam boa eficiência para serem utilizadas nas seções compostas com alma em compensado. As ligações de nó de pórtico com ligação alma/mesa pregadas podem ser consideradas rígidas na maioria dos casos estudados. / Plywood webbed structures have been applied in at several countries where timber structures are commonly used, giving civil engineers and builders one more option when looking for a safe, efficient and durable construction system. This work presents theoretical and experimental studies about plywood-webbed structures, with emphasis on nailed plywood webbed structures. The aim of this work is to develop design criteria for these structures to be used in Brazil. Several design criteria where found in the bibliography, some of them using simplifications for shear deflexions and joint deformations. Experimental results of nailed plywood webbed beams were compared with theoretical values from formulations found in the bibliography, concluding that EUROCODE 5 gives the best design criteria for nailed composite beams. Based on plywood webbed knee joints tests, a methodology to calculate the joint rigidity was proposed. The conclusions show the efficiency of this system and that nailed plywood webbed knee joints can be considered fixed for the majority of the specimens tested.

Orientador: Paulo Jose Rocha de Albuquerque / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-13T04:04:46Z (GMT). No. of bitstreams: 1 Melo_BarbaraNardi_M.pdf: 6782464 bytes, checksum: 2db509605b90c7d9ce2ae5bbdafbb1c1 (MD5) Previous issue date: 2009 / Resumo: A dificuldade de se atingir a ruptura dos elementos de fundação nos ensaios estáticos fez com que, ao longo de várias décadas, diversos métodos de extrapolação da curva carga vs recalque fossem sugeridos por inúmeros pesquisadores, no intuito de determinar a carga de ruptura, destacando-se os métodos propostos por Van der Veen (1953), Mazurkiewics (1972), Décourt (1996) e NBR 6122/1996. Porém, a experiência confirma que os resultados podem variar consideravelmente entre um método e outro. Este trabalho destaca o Conceito de Rigidez proposto por Décourt (1996, 2008), método que, nos últimos anos, vem sendo utilizado pela comunidade geotécnica e é destacado pelo autor como um método que oferece informações de resistência de ponta e atrito lateral, além da carga de ruptura em provas de carga comuns, ou seja, sem instrumentação. Com a interpretação dos resultados, levantados em estacas do tipo escavadas, hélice contínua, raiz, ômega, pré-moldadas, apiloadas e metálicas em seis campos experimentais localizados nas cidades de Campinas/SP, Recife/PE, Vitória/ES, Londrina/PR, Ilha Solteira/SP e Brasília/DF obtiveram-se valores satisfatórios de carga de ruptura convencional em provas de carga levadas a grandes deslocamentos e algumas restrições em provas de carga interrompidas prematuramente. Os resultados de atrito lateral comparados com resultados de estacas instrumentadas trazem valores satisfatórios, ou seja, dentro dos domínios. / Abstract: The difficulty of reaching the rupture of the foundation elements in the static loading made that along several decades several methods of extrapolation of the load - settlement curve were suggested by many researchers, with the intent of determining the load failure, such as the methods proposed by Van der Veen (1953), Mazurkiewics (1972), Décourt (1996) and NBR 6122/1996. But the experience confirms that the obtained results can vary considerably from one method to another. This work details the Concept of Rigidity, proposed by Décourt (1996, 2008), a method that in the last years it has been used by the geotechnical community and which the author claims as a method that provides information on tip resistance and lateral friction, along with the load at failure in common load tests, it means, without instrumentation. Whit the interpretation results raised in bored piles, continuous flight auger, root, omega, driven concrete, "hamered" and metal pile in six experimental fields localized in Campinas/SP, Recife/PE, Vitória/ES, Londrina/PR, Ilha Solteira/SP and Brasilia/DF got satisfactory values of conventional load failure in load tests carried to big movements and some restrictions in load tests not carried to failure. The lateral friction results compared with load tests on instrumented piles results show satisfactory values, it means, in the domains. / Mestrado / Geotecnia / Mestre em Engenharia Civil

Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-17T21:10:56Z No. of bitstreams: 2 Dissertação - Laena Furtado Borges - 2017.pdf: 2090414 bytes, checksum: afc3416e502ab5aedc5390b7986a9fcf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T13:53:29Z (GMT) No. of bitstreams: 2 Dissertação - Laena Furtado Borges - 2017.pdf: 2090414 bytes, checksum: afc3416e502ab5aedc5390b7986a9fcf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T13:53:29Z (GMT). No. of bitstreams: 2 Dissertação - Laena Furtado Borges - 2017.pdf: 2090414 bytes, checksum: afc3416e502ab5aedc5390b7986a9fcf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we will present some concepts of quasi-Einstein metrics. From this, we will enunciate and demonstrate rigidity results for quasi-Einstein metrics until we have enough material to demonstrate a stiffness result for quasi-Einstein metrics of dimension two. Finally, we will give some concepts of Kähler metrics, prove a theorem and finally demonstrate a corollary that connects the main theorem of our work with Kähler metrics. / Nesse trabalho, apresentaremos alguns conceitos de métricas quasi-Einstein. A partir disso, enunciaremos e demonstraremos resultados de rigidez para métricas quasi-Einstein, até que tenhamos material suficiente para a demonstração de um resultado de rigidez para métricas quasi-Einstein em dimensão dois. Por fim, daremos alguns conceitos de métricas kähler, provaremos um teorema e por fim demonstraremos um corolário que conecta o teorema principal do nosso trabalho com as métricas Kähler.

This study investigates the market conditions under which the Greek manufacturing sectors operate, and provides a formal measurement and determination of the observed degree of rigidity in nominal prices using panel modelling techniques. Two parameters in particular are found to capture the essence of market imperfections and price rigidity arising from various sources: the first parameter is conjectural variation elasticity which defines the degree of market divergence from perfect competition; and the last parameter refers to the speed of price adjustment towards the equilibrium level, which is estimated along with a set of important factors that affect this parameter. The data sample of this research consists of 56 3-digit manufacturing sectors, as defined by Eurostat (NACErev2) over the period 1980-2012, while the econometrical approach mainly incorporates the Fixed and Random Effects Model for panel data. The estimation process is divided into four steps: in the first step, the degree of market power and the speed of price adjustment are estimated for the whole manufacturing industry; in the second step, the same process is reiterated for the 3-digit sectors individually; in the third step the estimations are conducted for each year over 1980-2012; in the last step, the effects of a set of variables on the speed of price adjustment are estimated in order to provide an adequate interpretation of how market imperfections and price rigidities can be formed and how they relate to each other. By using the Greek economy as a case study, the empirical results provide significant evidence of a degree of market power similar to the one of a duopoly accompanied by relatively slow price adjustment in the 56 manufacturing sectors and the 33 years over 1980-2012.

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I have targeted to analyze the patterns of wage development in the changing macroeconomic conditions. According to the expectations the evolution of nominal and real wages is inter alia positively affected by the changes in labor productivity and negatively influenced by the deviation of unemployment rate from NAIRU. The evidence of procyclical behavior of real wages is not very robust as there was not found significant correlation in the time of decreasing real GDP. The most of results of the models applied on post Lehman Brothers period are consistent with the regressions based on complete data set. The chosen data proved to be not very suitable to show the extent of wage rigidity. The significant negative relationship between the development of real wages and changes in inflation rate implies the visibility of symptoms of wage rigidities even when we work with average macroeconomic variables.

De jure and De facto Rigidity in the General Terms for Natural Kinds”. This paper will argue that one of rigidity’s central problems in general terms for natural kinds, is consequence of not distinguishing between de jure rigid terms and de facto rigid terms on these cases. The paper claims that necessary identity sentences defended by Kripke in Naming and Necessity consider the term’s occurrence to designate a same kind (kinds which share the transworld relation of being one same kind) through two rigidity terms, a de jure one, and a de facto one. This allows to explain the problems that arise from the notion of rigidity in the case of general terms for natural kinds, since it maintains the causal connection requirements, while at the same time it enunciates the identity criterion between these kinds, through the essential property(ies) of the abovementioned kind. / En este escrito se argumentará que uno de los problemas centrales de la rigidez en los términos generales para clases naturales es consecuencia de no distinguir entre términos rígidos de jure y términos rígidos de facto en dichos casos. Se sostiene que los enunciados de identidad necesarios defendidos por Kripke en Naming and Necessity consideran la ocurrencia de términos que designan a una misma clase (clases que poseen entre sí la relación transmundana de ser una misma clase) a través de dos términos rígidos, uno de jure y uno de facto. Esto permite explicar los problemas que la noción de rigidez plantea en los casos de los términos generales para clases naturales, pues mantiene los requerimientos de conexión causal y a su vez enuncia el criterio de identidad entre tales clases, a través de la(s) propiedad(es) esencial(es) de dicha clase.

This thesis is concerned with two problems in the Calculus of Variations touching on two central aspects of Materials Science: the structure of solid matter and its dynamic behavior. The problem pertaining to the first aspect is the analysis of the rigidity properties of possibly branched microstructures formed by shape memory alloys undergoing cubic-to-tetragonal transformations. On the basis of a variational model in the framework of linearized elasticity, we derive a non-convex and non-discrete valued differential inclusion describing the local volume fractions of such structures. Our main result shows the inclusion to be rigid without additional regularity assumptions and provides a list of all possible solutions. We give constructions ensuring that the various types of solutions indeed arise from the variational model and quantitatively describe their rigidity via H-measures. Our contribution to the second aspect is a conditional result on the convergence of the Allen-Cahn Equations to multi-phase mean curvature flow, which is a popular model for grain growth in polychrystalline metals. The proof relies on the gradient flow structure of both models and borrows ideas from certain convergence proofs for minimizing movement schemes.:1 Introduction 1.1 Shape memory alloys 1.2 Multi-phase mean curvature flow 2 Branching microstructures in shape memory alloys: Rigidity due to macroscopic compatibility 2.1 The main rigidity theorem 2.2 Outline of the proof 2.3 Proofs 3 Branching microstructures in shape memory alloys: Constructions 3.1 Outline and setup 3.2 Branching in two linearly independent directions 3.3 Combining all mechanisms for varying the volume fractions 4 Branching microstructures in shape memory alloys: Quantitative aspects via H-measures 4.1 Preliminary considerations 4.2 Structure of the H-measures 4.3 The transport property and accuracy of the approximation 4.4 Applications of the transport property 5 Convergence of the Allen-Cahn Equation to multi-phase mean curvature flow 5.1 Main results 5.2 Compactness 5.3 Convergence 5.4 Forces and volume constraints

Recent research has shown that a significant number of the falls from elevation occur when laborers are working on unfinished structures. Workers walking on wood I-joists on roofs and floors are prone to fall hazards. Wood I-joists have been replacing dimension lumber for many floor systems and a substantial number of roof systems in light-frame construction. Wood I-joists are designed to resist axial stresses on the flanges and shear stresses on the web while minimizing material used. However, wood I-joists have poor resistance to applied lateral and torsional loads and are susceptible to lateral-torsional buckling instability. Workers walking on unbraced or partially braced wood I-joists can induce axial and lateral forces as well as twist. Experimental testing demonstrated that workers cause lateral-torsional buckling instability in wood I-joists. However, no research was found related to the lateral-torsional buckling instability induced by individuals walking on the wood I-joists. Furthermore, no research was found considering the effects of the supported end conditions and partial bracing in the lateral-torsional buckling instability of wood I-joists. The goal of this research was to derive mathematical models to predict the dynamic lateral-torsional buckling instability of wood composite I-joists loaded by individuals walking considering different supported end conditions and bracing system configurations. The dynamic lateral-torsional buckling instability was analyzed by linearly combining the static lateral-torsional buckling instability with the lateral bending motion of the wood I-joists. Mathematical models were derived to calculate the static critical loads for the simply supported end condition and four wood I-joist hanger supported end conditions. Additionally, mathematical models were derived to calculate the dynamic maximum lateral displacements and positions of the individual walking on the wood I-joists for the same five different supported end conditions. Three different lean-on bracing systems were investigated, non-bracing, one-bracing, and two-bracing systems. Mathematical models were derived to calculate the amount of constraint due to the lean-on bracing system. The derived mathematical models were validated by comparison to data from testing for all supported end conditions and bracing systems The predicted critical loads using the static buckling theoretical models for the non-bracing system and the static buckling theoretical models combined with the bracing theoretical models for the simply and hanger supported end conditions agreed well with the critical loads obtained from testing for the two wood I-joist sizes investigated. The predicted maximum lateral displacements and individual positions using the bending motion theoretical models for the simply and hanger supported end conditions agreed well with the corresponding maximum lateral displacements and individual positions obtained from testing for both wood I-joist sizes. Results showed that; a) the supported end condition influenced the critical loads, maximum lateral displacements and individual positions, b) the bracing system increased the critical loads and reduced the maximum lateral displacements, c) the critical load increased as the load position displaced away from the wood I-joist mid-span, d) the critical load reduced as the initial lateral displacement of the wood I-joist increased and e) the wood I-joist mid-span was the critical point in the dynamic lateral-torsional buckling instability. / Ph. D.

Understanding how different parameters affect the dynamic response of high-speed railway bridges is crucial to selecting an efficient structural form. Despite existing numerous publications within this field, only few address the importance of torsional deformations. The main objective of this thesis is to investigate the influence of the torsional resistance of the deck on the dynamic response of an existing bridge. Ulla River Viaduct is presented as a case study, allowing to analyse some aspects of its design and what their alteration entails. To this end, 6 different 3D FE models are compared, 5 of which show a modification from the original configuration. In addition, several positions of the train are considered to contrast the effects when the torsional modes are excited. The performed dynamic calculations are based on the implicit direct integration procedure. The analysis of the case study demonstrates the benefit of closing the torsional circuit of the deck. The results also evidence the need of including torsional effects in its dynamic assessment when low values of torsional rigidity are considered. All this is not easy when simplified 2D or 3D beam models are used. As a final remark, the original design of the Ulla River Viaduct is found highly efficient from a dynamical point of view.