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Neste trabalho é realizado um estudo da sensibilidade de estruturas de paredes de concreto moldadas no local quanto à deslocabilidade dos seus apoios, a fim de determinar sua influência na redistribuição dos esforços nos elementos estruturais. Para tanto, utiliza-se um modelo de referência, que discretiza a superestrutura através de elementos finitos de casca e avalia a interação solo-estrutura através de métodos iterativos, que consideram a rigidez da edificação, a heterogeneidade do solo e o efeito de grupo das fundações. Para quantificar e avaliar os efeitos da interação solo-estrutura realiza-se um estudo paramétrico, em que a influência do tipo de fundação (profunda ou superficial), número de pavimentos (cinco, dez e quinze) e a forma da edificação (quadrada e alongada) são avaliadas. Um modelo simplificado de análise estrutural, em que a interação solo-estrutura é considerada e as paredes de concreto são discretizadas por elementos de barra, acima do segundo pavimento, foi proposto e avaliado, por meio de comparações com os resultados do seu respectivo modelo de referência. Por fim, foram discutidas as implicações e a importância da consideração do efeito da deslocabilidade dos apoios e feitas recomendações sobre a modelagem simplificada. Observa-se: alívio dos apoios com maiores recalques, tendência de uniformização dos recalques, maior influência nas paredes inferiores e suficiência dos cincos primeiros pavimentos na definição de rigidez solo/estrutura. / In this paper, a sensitivity study was carried out of concrete reinforced walls molded on site regarding the displaceability of their supports, in order to determine their influence on the redistribution of internal forces in structural elements. In order to do this, a reference model was used, which discretizes the superstructure using shell finite elements and evaluates the soil-structure interaction by iterative methods that consider the rigidity of the building, the soil heterogeneity and the group effect of foundations. To quantify and assess the effects of soil-structure interaction, a parametric study was carried out in which the influence of the type of foundation (deep or shallow), number of floors (five, ten and fifteen) and the shape of the building (square, elongated) are evaluated. A simplified model of the structural analysis, in which the soil-structure interaction is considered and the concrete walls are discretized by bar elements, above the second floor, was proposed and evaluated by comparing its respective reference model with the results. Finally, the implications and the importance of considering the effect of displaceability of the supports were discussed and recommendations were made about the simplified modeling. The analysis denotes: relief of reactions on supports with larger settlements, tendency of settlements standardization, larger influence on the lower walls and that the first five floors are enough to define the relative soil/structure stiffness.

Neste trabalho é realizado um estudo da sensibilidade de estruturas de paredes de concreto moldadas no local quanto à deslocabilidade dos seus apoios, a fim de determinar sua influência na redistribuição dos esforços nos elementos estruturais. Para tanto, utiliza-se um modelo de referência, que discretiza a superestrutura através de elementos finitos de casca e avalia a interação solo-estrutura através de métodos iterativos, que consideram a rigidez da edificação, a heterogeneidade do solo e o efeito de grupo das fundações. Para quantificar e avaliar os efeitos da interação solo-estrutura realiza-se um estudo paramétrico, em que a influência do tipo de fundação (profunda ou superficial), número de pavimentos (cinco, dez e quinze) e a forma da edificação (quadrada e alongada) são avaliadas. Um modelo simplificado de análise estrutural, em que a interação solo-estrutura é considerada e as paredes de concreto são discretizadas por elementos de barra, acima do segundo pavimento, foi proposto e avaliado, por meio de comparações com os resultados do seu respectivo modelo de referência. Por fim, foram discutidas as implicações e a importância da consideração do efeito da deslocabilidade dos apoios e feitas recomendações sobre a modelagem simplificada. Observa-se: alívio dos apoios com maiores recalques, tendência de uniformização dos recalques, maior influência nas paredes inferiores e suficiência dos cincos primeiros pavimentos na definição de rigidez solo/estrutura. / In this paper, a sensitivity study was carried out of concrete reinforced walls molded on site regarding the displaceability of their supports, in order to determine their influence on the redistribution of internal forces in structural elements. In order to do this, a reference model was used, which discretizes the superstructure using shell finite elements and evaluates the soil-structure interaction by iterative methods that consider the rigidity of the building, the soil heterogeneity and the group effect of foundations. To quantify and assess the effects of soil-structure interaction, a parametric study was carried out in which the influence of the type of foundation (deep or shallow), number of floors (five, ten and fifteen) and the shape of the building (square, elongated) are evaluated. A simplified model of the structural analysis, in which the soil-structure interaction is considered and the concrete walls are discretized by bar elements, above the second floor, was proposed and evaluated by comparing its respective reference model with the results. Finally, the implications and the importance of considering the effect of displaceability of the supports were discussed and recommendations were made about the simplified modeling. The analysis denotes: relief of reactions on supports with larger settlements, tendency of settlements standardization, larger influence on the lower walls and that the first five floors are enough to define the relative soil/structure stiffness.

Rapid Rotational Foam Molding (RRFM) is a novel patent-pending process that was designed and developed to maximize the synergistic effects resulting from the deliberate combination of extrusion and rotational foam molding and thereby serve as a time-andenergy efficient technology for the manufacture of integral-skin rotationally molded foams of high quality. This thesis presents a thorough study of the scientific and engineering aspects related to the evolution of the RRFM process and its feasibility. This innovative processing technology was assessed and verified through a battery of planned experimental trials conducted utilizing an in-house custom-built industrial-grade lab-scale experimental setup. The experimental trials involved a variety of polypropylene (PP)- based foamable formulations with a chemical blowing agent (CBA) that were compounded and processed by utilizing an extruder and then foamed and injected as a foamed core, instantly, into the cavity of a suitable non-chilled rotationally molded hollow shell made of non-foamed pulverized PP grades. The investigated mold shapes included a cylindrical shaped mold and a rectangular flat shaped mold. The obtained moldings were examined for the quality of the skin surface, the skin-foam interface, and the achieved foam morphologies that were characterized in terms of foam density, average cell size, and average cell density. Optimal processing parameters were successfully determined for three different PP skin-foam formulation combinations. The accomplished reduction in processing time and energy consumption by implementing RRFM were substantial. A variety of processing impediments that hindered the efficiency of the single-charge conventional rotational foam molding practice were resolved by implementing RRFM; these include: the foam/skin invasion into the skin/foam layer of the manufactured article and the premature decomposition of CBA during compounding or subsequent rotational foam molding processing steps. / UOIT

A popular habitation must be understood not only as a simple habitation unit but also as a comfortable, safe and salubrious space. Therefore it is necessary a study regarding the use of alternative materials, as well as the more indicated architectonic typologies. Rubber residuals of tires are being used in different areas of civil construction, as a thin aggregate of concrete, revetment panels or in acoustics isolation. The application of the system of pre-molded plates, constructed with recyclable material has been used in popular buildings for most two decades in the city of Santa Cruz do Sul, RS. The construction system is executed in parte by prisoner workers, with the concrete plates being produced in the penitentiary, and through the self-construction of residencies with areas of 40 e 60m² by selfparticipation. However are still lacking scientific data on the constructive characteristics of these houses, as well as a after-occupational evaluation. Thus, the present Work presents data referring to the assays of soft and hard body, water resistant, thermal comfort and resistance to fire, as well as presents the base of the after-occupational evaluation of already existing houses for with new architectural proposals. The assays had shown that not all the analyzed parameters are inside the technical norms scales (NBRs). To take care of the necessities of the users of future habitation units, new architectural proposals for houses with 29,13m ², 29,28m ², 44,32m ² and 59,60m ² are presented using the constructive system with molded panels with addition of rubber residue. / Uma habitação popular deve ser entendida não somente como uma simples unidade habitacional, mas também como um espaço confortável, seguro e salubre; sendo assim é necessário estudo sobre a utilização de materiais alternativos, bem como as tipologias mais indicadas. Resíduos de borracha de pneu estão sendo utilizados em diversas áreas da construção civil, sendo como um agregado fino no concreto, painéis de revestimento ou no isolamento acústico. A aplicação do sistema de placas pré-moldadas, construídas com material reciclável (resíduo de borracha) é empregada em edificações populares, há quase duas décadas, na cidade de Santa Cruz do Sul - RS. O sistema construtivo é executado em parte com a utilização de mão de obra carcerária, com as placas sendo produzidas na Penitenciária e pela autoconstrução de residências com áreas de 40 e 60 m² no sistema de mutirão. No entanto ainda faltaram dados científicos sobre as características construtivas destas casas, bem como uma avaliação pós-ocupacional. Assim, o presente Trabalho apresenta dados referentes aos ensaios de corpo mole e duro, estanqueidade à água, conforto térmico e resistência ao fogo, bem como apresenta a base da avaliação pós-ocupacional das casas já existentes, com novas propostas arquitetônicas. Os ensaios mostraram que não todos os parâmetros analisados estão dentro do previsto pelas normas técnicas (NBRs). Para atender às necessidades dos usuários e de futuras unidades habitacionais, novas propostas arquitetônicas para casas com 29,13m², 29,28m², 44,32m² e 59,60m² são apresentadas utilizando o sistema construtivo com placas pré-moldadas com adição de resíduo de borracha.

The consequences of microplastics spreading from surfaces made from molded rubber granules has a negative impact on our ecosystems, plants, and other living organisms. As our understanding of these negative environmental impacts grows, the need to shape and enforce effective measures to reduce this spread also increases. This creates a challenge for the political environmental management on both a national and municipal level. This study investigates the condition of Swedish municipalities and the possibilities they have to take effective measures to reduce the spread of microplastics in facilities that use molded rubber granules, in a time when both knowledge and experience of molded rubber granules is still limited. The study also examines whether the municipality’s participation during the forming of new environmental policies impacts the final outcome. The theory is based on implementation and participitation in management and politics. The results are based on interviews with representatives from nine Swedish municipalities, all geographically spread out and of varying size. Even if the accountable party at the municipalities admitted that their surfaces made from molded rubber granules spread microplastics, they lacked knowledge on the spread’s environmental impact. Both lack of sufficient resources and possibility to take effective action due to politically conflicting goals, confirmed several of the challenges connected to participation and implementation within politics. The study finds that the lack of knowledge on the environmental impact of molded rubber granules, the municipalities’ limited resources and the conflicting goals between the requirements of accessibility and environmental requirements affect the municipalities’ possibilities to implement measures through an environmental policy. Through an increased cooperation between state and municipalities during the forming and implementation of environmental policies the goal fulfillments would likely improve. / Effekterna av mikroplastspridning från ytor av gjutet gummigranulat påverkar både ekosystem, växter och levande organismer negativt. I takt med att förståelsen för mikroplasters negativa miljöpåverkan ökar växer behovet av att utforma och vidta effektiva åtgärder för att minska mikroplastspridningen. Detta utmanar den politiska miljöstyrningen på både statlig och kommunal nivå. Studien undersöker svenska kommuners förutsättningar för att vidta åtgärder som motverkar spridning av mikroplast från anläggningar med gjutet gummigranulat. Denna studie undersöker också hur kommuners deltagande vid utformning av nya miljöpolicys kan påverka måluppfyllnaden. Den teoretiska ramen utgörs av genomförande och deltagande inom politik och förvaltning. Resultatet baseras på intervjuer med representanter för nio geografiskt spridda svenska kommuner av varierande storlek. De ansvariga på kommunerna var medvetna om att deras ytor av gjutet gummigranulat sprider mikroplast men saknade djupare kunskap om miljöeffekterna av mikroplastspridningen. Otillräckliga ekonomiska resurser och politiska målkonflikter är några av de utmaningar som är kopplade till deltagande och genomförande inom politik och förvaltning. Kommunernas inställning till alternativa material såsom gjutet korkgranulat och åtgärder genom granulatfällor var positiv. Studien finner att bristen på kunskap om gjutet gummigranulats miljöeffekter, kommunernas resursbegränsningar och målkonflikten mellan tillgänglighetskrav och miljökrav påverkar kommunernas förutsättningar att implementera åtgärder genom en miljöpolicy. Med ett ökat deltagande genom samverkan mellan statlig och kommunal nivå vid utformning och implementering av miljöpolicys skulle måluppfyllnaden sannolikt förbättras.

ABSTRACT Federal regulations have recognized that arc flash hazards are a critical source of potential injury. As a consequence, in order to work on some electrical equipment, the energy source must be completely shut-down. However, power distribution systems in mission critical facilities such as hospitals and data centers must sometimes remain energized while being maintained. In recent years the Arc Flash Hazard Analysis has emerged as a power system tool that informs the qualified technician of the incident energy at the equipment to be maintained and recommends the proper protective equipment to wear. Due to codes, standards and historically acceptable design methods, the Arc Flash Hazard is often higher and more dangerous than necessary. This dissertation presents detailed methodology and proposes alternative strategies to be implemented at the design stage of 600 volt facility power distribution systems which will decrease the Arc Flash Hazard Exposure when compared to widely used code acceptable design strategies. Software models have been developed for different locations throughout a power system. These software model simulations will analyze the Arc Flash Hazard in a system designed with typical mainstream code acceptable methods. The model will be changed to show implementation of arc flash mitigation techniques at the system design level. The computer simulations after the mitigation techniques will show significant lowering of the Arc Flash Hazard Exposure.

The theses is focused on efficient use of numerical methods in development of low-voltage switching devices, namely to create a physically correct and reliable numerical model of the temperature field to find an application in the design of the current path of a device for various operating conditions. The creation of this numerical model requires not only correct inclusion of all modes of heat transfer - conduction, convection and radiation, but also correct solution of problematic transient resistance - both electrical and thermal in electrical contacts at different stages of usage. Therefore an essential part of the theses forms a thorough experimental analysis of the necessary material properties and dependencies which forms input data for the numerical model that is based on the finite volume method. The last part of the theses deals with debugging and verification of numerical model to correspond with experimentally obtained data. The result of the theses is the numerical model which is able to solve correctly both steady and various transient states of swiching devices.

This master‘s thesis deals with the thermal overload trip unit in automatically operated electrical switching devices. The first part of this thesis serves as a basis for a design of thermostatic bimetal element in electrical switching device. The thesis presents important parameters and calculation principles needed for the design of bimetal element. The thesis further describes the operating principle of thermal trip unit and its possible design solutions. The main part is devoted to analytical calculation and measurement of specific thermostatic bimetal type contained in thermal trip unit of molded case circuit breaker. It is measurement of force and deflection, depending on temperature change. In the next part a numerical model of the bimetallic strip was created and its deflection was simulated. The analytical results are compared with the measured and simulated results at the end of the thesis.

The Master’s thesis is concentrated on a thermoplastic injection technology and in particular on heat balance of tool. In the theoretical part, literary study, is shortly described actual knowledge in these branches. In the practical part is solved the design of tool for production of the specific plastic part. This thesis insists on the proposal and selection of applicable cooling system in the tool and on optimization of the technology parameters of injection proces. Those proposals are evaluated by simulation software Cadmould 3D-F. In the end of this thesis is performed the economic analysis of plastic part production costs.