O núcleo resistente, considerado um dos principais elementos componentes dos sistemas estruturais de edifícios de andares múltiplos, quando associado ao sistema de contraventamento, consegue conferir à estrutura um razoável acréscimo de rigidez. O núcleo é ainda o único elemento estrutural capaz de resistir isoladamente a todos os esforços atuantes na estrutura de um edifício, contribuindo na determinação mais precisa dos seus deslocamentos. Baseado nestes fatores, acredita-se que as diferentes modelagens, adotadas para o núcleo, proporcionarão diferentes resultados para a mesma estrutura de contraventamento. Este trabalho tem como principal objetivo analisar a influência que estas modelagens exercem na estrutura de contraventamento. Inicialmente, são apresentadas algumas das modelagens mais utilizadas para o núcleo. Com estas modelagens foram processadas algumas estruturas, e os diversos resultados obtidos utilizados no processo comparativo. Para o processamento foram consideradas análises em teoria de primeira e segunda ordem e, para as fundações, vinculação rígida. Não serão consideradas as deformações por esforço cortante nos elementos. / Resistant cores, are considered one of the principal elements of the structural systems of multistory buildings. When associated to the bracing structure, it gives to the structure a reasonable stiffness increment. The core is still the only structural element capable to resist separately all the efforts in the structure of a building, contributing to a more accurate determination of its displacements. Based on these factors, it is believed that different modeling adopted for the cores will provide different results for the same bracing structure. The main aim of this work is to analyze the influence that these modeling exerts on the bracing structure. First, some of the most used core modeling were presented. Then some structures were processed, using these modeling. The several obtained results were compared. For all the analysis it was considered the first and second order theory and rigid connections for the foundations. Shear deformation were not considered in the elements.

This study investigated the vibration serviceability of timber structures with dowel-type connections. It addressed the use of such connections in cutting-edge timber structures such as multi-storey buildings and long-span bridges, in which the light weight and flexibility of the structure make it possible that vibration induced by dynamic forces such as wind or footfall may cause discomfort to occupants or users of the structure, or otherwise impair its intended use. The nature of the oscillating force imposed on connections by this form of vibration was defined based on literature review and the use of established mathematical models. This allowed the appropriate cyclic load to be applied in experimental work on the most basic component of a dowel-type connection: a steel dowel embedding into a block of timber. A model for the stiffness of the timber in embedment under this cyclic load was developed based on an elastic stress function, which could then be used as the basis of a model for a complete connector. Nonlinear and time-dependent behaviour was also observed in embedment, and a simple rheological model incorporating elastic, viscoelastic and plastic elements was fitted to the measured response to cyclic load. Observations of the embedment response of the timber were then used to explain features of the behaviour of complete single- and multiple-dowel connections under cyclic load representative of in-service vibration. Complete portal frames and cantilever beams were tested under cyclic load, and a design method was derived for predicting the stiffness of such structures, using analytical equations based on the model for embedment behaviour. In each cyclic load test the energy dissipation in the specimen, which contributes to the damping in a complete structure, was measured. The analytical model was used to predict frictional energy dissipation in embedment, which was shown to make a significant contribution to damping in single-dowel connections. Based on the experimental results and analysis, several defining aspects of the dynamic response of the complete structures, such as a reduction of natural frequency with increased amplitude of applied load, were related to the observed and modelled embedment behaviour of the connections.

Biobased thermoset resins were synthesized by functionalizing the tall oil fatty acid with hydrogen peroxide and then methacrylic anhydride. The obtained resins were characterized by FTIR to confirm the conversions. The cross-linking ability of the resins were checked by curing experiments and followed by DSC analysis regarding the extent of cross linking. TGA analysis was conducted to identify the thermal degradation patterns of cured resins. The obtained resins (blended with or without 33wt% styrene) were used as matrix and knitted viscose fibers were used as reinforcements to make bio-based composites. Ten layers of knitted viscose fibers were stacked crosswise (0/90⁰С) and hand lay-up impregnation was performed. The fiber ratio of all composites was around 63-66%. The composites were characterized by flexural testing, dynamic mechanical thermal analysis and charpy testing. This work demonstrates that manufacture of composites with both matrix and reinforcement fiber coming from renewable resources is feasible, and the resulted composites have satisfied mechanical performance. / Program: MSc in Resource Recovery - Sustainable Engineering

Thesis. 1976. M.Arch.--Massachusetts Institute of Technology. Dept. of Architecture. / Microfiche copy available in Archives and Rotch. / Bibliography: leaf 38. / by David R. Mayner. / M.Arch.

A pesquisa parte-se da hipótese de que critérios quantitativos e qualitativos de desempenho ambiental são definidores da expressão formal da arquitetura paramétrica do edifício alto. Pretende-se comprová-la com a criação e a aplicação de um método de projeto arquitetônico que relacione avaliação paramétrica de desempenho ambiental e a geração da forma. Essa hipótese surgiu da utilização sem critérios claros e precisos de desempenho ambiental na geração das formas dos edifícios altos, e vem de encontro ao conceito contemporâneo de conforto, da adaptação, das respostas específicas. O objetivo geral do trabalho é propor uma metodologia de projeto arquitetônico que relacione avaliação paramétrica de desempenho ambiental com critérios qualitativos e quantitativos e a geração da forma. Ou seja, compreender como os critérios de desempenho ambiental podem informar a geração da forma utilizando para isso, ferramentas paramétricas como no caso do Rhinoceros e o seu plug-in Grasshopper. A pesquisa apresenta os edifícios ícones de desempenho ambiental, discutindo os parâmetros de projeto, o desempenho real e as novas questões do conforto adaptativo. Além disso, são apresentados os critérios de desempenho utilizados para informar a metodologia de projeto paramétrico de geração da forma. Discute-se o papel da ventilação natural e das áreas envidraçadas no projeto do edifício alto. A questão do projeto paramétrico e generativo é introduzida, apresentando-se os principais conceitos, as tecnologias, os processos e as ferramentas. Por fim, o método resulta em um conjunto de diretrizes de projeto e critérios de desempenho, desenvolvidos para a formulação dessa proposta de avaliação, podendo ser visualizado, no final, em um modelo teórico do edifício alto para a cidade de São Paulo. Os produtos da tese foram: (I) critérios qualitativos e quantitativos de desempenho ambiental do edifício alto, (II) metodologia de projeto paramétrico informada por critérios ambientais, (III) solução projetual para edifícios de escritórios que utilizem ventilação e iluminação natural como estratégia principal para atingir o conforto dos usuários e reduzir o consumo de energia. / The research starts from the hypothesis that quantitative and qualitative criteria for the environmental performance are defining the formal expression of parametric architecture of tall building. We intend to prove it with the creation and implementation of a method for architectural design that relates parametric evaluation of environmental performance and the generation of form. This hypothesis arose from the use without clear and precise criteria of the environmental performance in form generating of tal buildings, and comes against the contemporary concept of comfort, the adaptation of specific responses. The general objective of this work is to propose an architectural design methodology that relates parametric evaluation of environmental performance with qualitative and quantitative criteria and the generation of form. Understand how environmental performance criteria can inform the generation of form using, parametric tools as the Rhinoceros and its plug-in Grasshopper. The research presents icons of environmental performance buildings, discussing the design parameters, real performance and new issues of adaptive comfort. Moreover, the performance criteria used to inform the methodology of parametric design generation are presented. It discusses the role of natural ventilation and glazed areas in the design of tal building. The issue of parametric and generative design is introduced, presenting key concepts, technologies, processes and tools. Finally, the method results in a set of design guidelines and performance criteria developed to the formulation of this evaluation proposal, and could be viewed at the end, in a theoretical model of the tall building to the city of São Paulo. The products of the thesis were: (I) qualitative and quantitative criteria for environmental performance of tall building (II) parametric design methodology informed by environmental criteria, (III) design solution for office buildings using natural ventilation and daylight as the main strategy to achieve the user comfort and reduce energy consumption.

Este trabalho apresenta o estudo do comportamento das estruturas tridimensionais de edifícios altos, sujeitos às ações verticais e laterais, considerando-se a rigidez transversal à flexão das lajes. A análise é feita pelo processo dos deslocamentos para todos elementos, onde emprega-se o Método dos Elementos Finitos na discretização das lajes e vigas em cada pavimento. O sistema estrutural não considera a presença dos núcleos estruturais, pilares ou pilares-parede submetidos à flexo-torção. As lajes também funcionam como diafragmas infinitamente rígidos em seu plano, sendo responsável pela compatibilidade dos deslocamentos correspondentes e pela transmissão das forças do vento aos pilares. Elaborou-se um programa de computador que automatiza o processo utilizado, e alguns exemplos são apresentados para comprovar sua validade. / This work presents a study about the behavior of three dimensional structures of tall buildings, subjected to vertical and lateral loads, considering the transverse bending stiffness of slabs. The analysis is done by stiffness method for all elements, and Finite Element Method is used in the discretization of slabs and beams of each floor. The structural system does not consider cores, columns or shearwalls that are subjected to warping effects. The slabs also act as diaphragms with an infinite stiffness in their plane, responsible displacements, for compatibility of the horizontal and so transmit the wind forces to the columns. A computer program is developed to get automatic the process utilized in the analysis, and some examples are presented to check its validity.

A pesquisa parte-se da hipótese de que critérios quantitativos e qualitativos de desempenho ambiental são definidores da expressão formal da arquitetura paramétrica do edifício alto. Pretende-se comprová-la com a criação e a aplicação de um método de projeto arquitetônico que relacione avaliação paramétrica de desempenho ambiental e a geração da forma. Essa hipótese surgiu da utilização sem critérios claros e precisos de desempenho ambiental na geração das formas dos edifícios altos, e vem de encontro ao conceito contemporâneo de conforto, da adaptação, das respostas específicas. O objetivo geral do trabalho é propor uma metodologia de projeto arquitetônico que relacione avaliação paramétrica de desempenho ambiental com critérios qualitativos e quantitativos e a geração da forma. Ou seja, compreender como os critérios de desempenho ambiental podem informar a geração da forma utilizando para isso, ferramentas paramétricas como no caso do Rhinoceros e o seu plug-in Grasshopper. A pesquisa apresenta os edifícios ícones de desempenho ambiental, discutindo os parâmetros de projeto, o desempenho real e as novas questões do conforto adaptativo. Além disso, são apresentados os critérios de desempenho utilizados para informar a metodologia de projeto paramétrico de geração da forma. Discute-se o papel da ventilação natural e das áreas envidraçadas no projeto do edifício alto. A questão do projeto paramétrico e generativo é introduzida, apresentando-se os principais conceitos, as tecnologias, os processos e as ferramentas. Por fim, o método resulta em um conjunto de diretrizes de projeto e critérios de desempenho, desenvolvidos para a formulação dessa proposta de avaliação, podendo ser visualizado, no final, em um modelo teórico do edifício alto para a cidade de São Paulo. Os produtos da tese foram: (I) critérios qualitativos e quantitativos de desempenho ambiental do edifício alto, (II) metodologia de projeto paramétrico informada por critérios ambientais, (III) solução projetual para edifícios de escritórios que utilizem ventilação e iluminação natural como estratégia principal para atingir o conforto dos usuários e reduzir o consumo de energia. / The research starts from the hypothesis that quantitative and qualitative criteria for the environmental performance are defining the formal expression of parametric architecture of tall building. We intend to prove it with the creation and implementation of a method for architectural design that relates parametric evaluation of environmental performance and the generation of form. This hypothesis arose from the use without clear and precise criteria of the environmental performance in form generating of tal buildings, and comes against the contemporary concept of comfort, the adaptation of specific responses. The general objective of this work is to propose an architectural design methodology that relates parametric evaluation of environmental performance with qualitative and quantitative criteria and the generation of form. Understand how environmental performance criteria can inform the generation of form using, parametric tools as the Rhinoceros and its plug-in Grasshopper. The research presents icons of environmental performance buildings, discussing the design parameters, real performance and new issues of adaptive comfort. Moreover, the performance criteria used to inform the methodology of parametric design generation are presented. It discusses the role of natural ventilation and glazed areas in the design of tal building. The issue of parametric and generative design is introduced, presenting key concepts, technologies, processes and tools. Finally, the method results in a set of design guidelines and performance criteria developed to the formulation of this evaluation proposal, and could be viewed at the end, in a theoretical model of the tall building to the city of São Paulo. The products of the thesis were: (I) qualitative and quantitative criteria for environmental performance of tall building (II) parametric design methodology informed by environmental criteria, (III) design solution for office buildings using natural ventilation and daylight as the main strategy to achieve the user comfort and reduce energy consumption.

Este trabalho apresenta o estudo do comportamento das estruturas tridimensionais de edifícios altos, sujeitos às ações verticais e laterais, considerando-se a rigidez transversal à flexão das lajes. A análise é feita pelo processo dos deslocamentos para todos elementos, onde emprega-se o Método dos Elementos Finitos na discretização das lajes e vigas em cada pavimento. O sistema estrutural não considera a presença dos núcleos estruturais, pilares ou pilares-parede submetidos à flexo-torção. As lajes também funcionam como diafragmas infinitamente rígidos em seu plano, sendo responsável pela compatibilidade dos deslocamentos correspondentes e pela transmissão das forças do vento aos pilares. Elaborou-se um programa de computador que automatiza o processo utilizado, e alguns exemplos são apresentados para comprovar sua validade. / This work presents a study about the behavior of three dimensional structures of tall buildings, subjected to vertical and lateral loads, considering the transverse bending stiffness of slabs. The analysis is done by stiffness method for all elements, and Finite Element Method is used in the discretization of slabs and beams of each floor. The structural system does not consider cores, columns or shearwalls that are subjected to warping effects. The slabs also act as diaphragms with an infinite stiffness in their plane, responsible displacements, for compatibility of the horizontal and so transmit the wind forces to the columns. A computer program is developed to get automatic the process utilized in the analysis, and some examples are presented to check its validity.

My objectives were to determine if nutritional benefits occur when animals are offered foods with compounds -- alkaloids, saponins, and tannins - that are potentially complementary. I hypothesized that food intake and digestibility increase when lambs consume plants such as alfalfa ALF that contain saponins or birdsfoot trefoil (BFT) that contain tannins when the basal diet is endophyte-infected tall fescue (TF) or reed canarygrass (RCG) both of which contain alkaloids. I predicted that the nutritional status of lambs would be enhanced if basal diets of alkaloid-containing grasses were supplemented with ALF or BFT. Lambs fed a basal diet of either endophyte-infected TF or RCG ate more food and consequently digested more dry matter, energy and nitrogen when supplemented with ALF or BFT. Lambs ingested more dry matter and digested more nutrients when fed a basal diet of RCG than one of TF, and supplementing with ALF and BFT was more beneficial for lambs fed TF than for lambs fed RCG. Increased intake of digestible nutrients was due to greater intake when lambs were offered more than one food, not due to an increase in digestibility. In pen trials meant to complement the field trials, lambs were offered an alkaloid-containing (either gramine or 5-methoxy-N,N-dimethyltryptamine) total mixed ration and supplemented with a food that contained saponins or tannins. All rations were isocaloric (3.3Mcal/kg) and isonitrogenous (14% CP). Lambs fed a ration with either alkaloid and offered a food containing saponin digested approximately the same amount of dry matter, energy, nitrogen, and NDF as lambs not offered saponin. When lambs were fed a ration with either alkaloid and supplemented with food that contained tannins, tannin consumption adversely affected dry matter, energy, and NDF digestibility, but lambs offered food with tannins increased dry matter intake, and as a result, they digested the same amount of dry matter, energy, and NDF as lambs not offered the food with tannins. Lambs offered tannin digested and retained more nitrogen than lambs not offered tannin. These findings indicate a nutritional advantage for sheep eating mixtures as opposed to monocultures of foods with different profiles of secondary compounds and nutrients.

Detta arbeta har utförts för att undersöka hur höstplantering av täckrotsodlad gran (Picea abies) och tall (Pinus sylvestris) överlever och utvecklas jämfört med vårplanterad. Detta i ett led för att se om man kan utöka planteringssäsongen för att få en jämnare arbetsbelastning över säsongen både i plantskolorna och ute i fält. Man har undersökt hur en planteringstidpunkt på sensommaren och hösten påverkar granplantors överlevnad jämfört med plantering på våren. Studien är utförd som en survey studie i södra Sverige på täckrotsplantor av gran som planterats på medelboniteter 2007-2009 och inventerats 2010. Höst och vårplanterade granplantor är jämförda parvis med samma planttyp, ålder, proveniens och geografiskt område. Följande saker har jämförts; plantor per hektar, höjdtillväxt, toppskottstillväxt, rothalsdiametern, frostskador, viltskador samt snytbaggeskador. Höstplantering av täckrotsodlad gran (Picea abies) ger ett lika bra resultat som vårplantering vad gäller överlevnad hos plantor. Höjdtillväxt och diametertillväxt blev något bättre på de höstplanterade plantorna jämfört med vårplanterade efterföljande vår. Höstplanterade plantor skadades något mer av frost än de vårplanterade gjorde, speciellt första säsongen. Vårplanterade plantor fick något mer viltskador än höstplanterade vilket kan bero på färre frostskador. Vårplanterade plantor skadades något mer av snytbagge än de höstplanterade. Snytbaggeskadorna var störst på de torra jordarna i östra området. Höstplantering av täckrotsodlad tall (Pinus sylvestris) gav ett lika bra resultat när det gäller överlevande plantor som gran. / This work has been performed in order to investigate if Norway spruce (Picea abies) and pine (Pinus sylvestris) container-grown seedlings planted in autumn gives the same quality as planting in spring in terms of surviving plants. This is in part to see if one can extend the planting season to get a more even workload over the season, both in nurseries and in the field. The study is designed as a survey study in Southern Sweden on container-grown seedlings of Norway spruce and pine planted 2007-2009 and inventoried 2010. The following things have been compared; plants per hectare, height growth, leading shoot growth, stem diameter, frost damage, damage by wild animals and pine weevil damage. Planting of Norway spruce (Picea abies) container-grown seedlings in autumn gives the same quality as planting in spring in terms of surviving plants. Height growth and diameter growth were slightly better the following season for seedlings planted in autumn compared to seedlings planted in spring. Seedlings planted in autumn were damaged by frost more than seedlings planted the spring, especially the first season. Seedlings planted in spring were slightly more damaged by wild animals than seedlings planted in autumn which may be because of less frost damage. Seedlings planted in spring were slightly a little more damaged by pine weevil than seedlings planted in autumn. Pine weevil damage was greatest in the arid soils in the eastern area. Container-grown seedlings of pine (Pinus sylvestris) planted in autumn gave equally good results as seedlings planted of Norway spruce.