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Proposta de modelos para estimativa do fator de redução da resistência à compressão de pilares castelados carregados axialmente
(Universidade Federal de São Carlos, 2024-04-08) Gomes, Arthur Filipe Freire; Christoforo, André Luis; https://lattes.cnpq.br/7623383075429186; https://orcid.org/0000-0002-4066-080X; https://lattes.cnpq.br/7112458774359627; https://orcid.org/0000-0003-4106-3879
Currently, castellated columns have been increasingly used in buildings due to their flexibility, easy compatibility and potential savings given their lower steel consumption. However, there is a lack of research and design methods for these elements. The influence of the openings on the load capacity of castellated columns has not yet been clearly defined in the literature. Studies on castellated beams can be easily found, however, studies on such profiles acting as pillars are scarce. In this context, numerical models based on finite elements developed with the aid of ABAQUS® software are developed. This parametric study with 1328 numerical models aims to evaluate the influence of the three main types of castellated openings (Peiner, Litzka and Anglo-Saxon), three expansion factors (k - 1.33, 1.50 and 1.67) and eight slenderness indices (λ - 25, 50, 75, 100, 125, 150, 175 and 200) in the behavior of axially loaded columns. In order to validate the numerical model, the load capacity obtained through a nonlinear analysis was compared with the valuesfound in three experimental studies and in ABNT NBR 8800 (2008 After validation, the resistant capacity of each model was determined through a nonlinear physical and geometric analysis around the largest and least inertia axis. The loads obtained by the castellated and full-web column were compared. The resistance reduction factors associated with global buckling (χ) for castellated columns were also compared to the values proposed by ABNT NBR 8800 (2008). Castellated columns had a lower resistance capacity than the full-web elements, especially the short columns. Castellated columns with larger openings showed a greater reduction in resistance capacity. Furthermore, the curve proposed by ABNT NBR 8800 (2008) may overestimate the resistant capacity of castellated columns for reduced slenderness indices (λ0) lower than 0.75. Finally, equations based on regression models were developed (with R2 values above 94.00) to estimate the resistance reduction factor associated with global buckling (χ) of the columns evaluated within the scope of this study.
Development of bio-inspired electromechanical devices based on PBMA-b-(PSS-r-PS) amphiphilic block copolymer
(Universidade Federal de São Carlos, 2024-04-08) Saccardo, Matheus Colovati; Scuracchio, Carlos Henrique; https://lattes.cnpq.br/0896060959622431; https://orcid.org/0000-0002-7723-0213; https://lattes.cnpq.br/3993645750766626; https://orcid.org/0000-0001-8119-3841
Technological advances in the aerospace, biomedical, and robotics industries stimulate the need for innovative and sustainable devices, such as electromechanical devices (EMDs), which are bio-inspired materials capable of mimicking biological systems in appearance, functionality, and operation. For practical applications, EMDs must combine several properties, such as i) high ionic conductivity, ii) flexibility, iii) mechanical resistance, and iv) chemical, thermal, and structural stability. Such properties can be obtained by engineering amphiphilic copolymers, which can self-assemble into well-defined morphologies with nanometric domains. Thus, it is possible to effectively dissociate ionic conductivity from mechanical properties, adjusting the flexibility, Young's modulus, and ionic conductivity according to the size of the blocks and the number of functional groups. Therefore, in this project, reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize the diblock copolymer Poly(butyl methacrylate)-b-(sulfonated polyneopentyl styrene-r-polystyrene) (PBMA-b-( PNeoSS-r-PS)). Subsequent thermolysis of the PNeoSS segments removes the neopentyl group, resulting in a sulfonated polystyrene-r-polystyrene (PSS-r-PS) backbone, yielding an amphiphilic block copolymer with ionic conductivity, which was used to prepare an EMD. In general, it can be concluded that RAFT polymerization is a robust and versatile technique that allows control of the degree of polymerization, molecular weight, polydispersity, and chemical composition of the copolymer. The copolymer presented a molecular weight of 65 kg.mol-1, with a 50% ratio between flexible and rigid blocks, alongside an 8.8% degree of sulfonation, lamellar morphology, capable for enhancing flexibility and ionic conductivity. Finally, the device was tested and characterized electromechanically using an electromechanical characterization system, showing promise for application as a sensor.
Histórico de expansão urbana e análise dos eventos de inundações no rio Sorocaba - SP
(Universidade Federal de São Carlos, 2024-04-08) Leite, Amanda Rodrigues; Arruda, Emerson Martins; https://lattes.cnpq.br/3883710507177933; https://lattes.cnpq.br/8055631622023281
Cuando la urbanización se produce sin una planificación adecuada, los ríos son vistos como un problema para la ciudad que se desarrolla en sus orillas. El sellado de suelos, la deforestación ribereña, las construcciones incómodas combinadas con la falta de estructuras adecuadas para el drenaje del agua, son solo algunos de los factores que interfieren con el curso natural de los cuerpos de agua urbanos, aumentando significativamente el riesgo de inundaciones. Esta investigación involucra el análisis de la dinámica ambiental del municipio de Sorocaba, así como el levantamiento de las inundaciones ocurridas en el río del mismo nombre, centrándose en el perímetro urbano del citado curso, vislumbrando así una comprensión de la dinámica ambiental, vinculado a aspectos de uso del suelo en sus márgenes, así como a la forma en que se apropia el relieve del área. Según las observaciones esbozadas, se entiende que son necesarias obras encaminadas a revitalizar los ríos urbanos para la calidad ambiental de los cursos de agua y de la propia cuenca, así como proyectos que valoren una mejor planificación urbana, con el objetivo de llegar a las raíces de los problemas relacionados con crecidas e inundaciones fluviales, siendo un factor conciliador en la relación río-ciudad.
“Òrìsà Ńjẹ, Ilé Asé Ńjẹ- Os Orixás Comem, O Terreiro Come”: uma etnografia da sacralização de animais em um Terreiro de Umbanda Traçada
(Universidade Federal de São Carlos, 2024-04-08) Silva, Julia Aparecida Rodrigues da; Vander Velden, Felipe Ferreira; https://lattes.cnpq.br/7289231173735671; https://lattes.cnpq.br/9718783230484134; https://orcid.org/0000-0003-0249-8474; Vale, Maíra Cavalcanti; Silva, Renata Nogueira; https://lattes.cnpq.br/2878356317160492; https://lattes.cnpq.br/0925621038607681
In the rituals of African religions, the sacralization of animals is an essential element in the connection between humans and deities: by immolating specific animals, the aim is to offer (feed) the deity and then distribute the animal's meat to everyone in the terreiro community and other followers present. Through sacralization (sacrifice), the animal's axé will serve as food for the Orixá (and for humans) because it acts and operates certain energy flows. The aim of this ethnography is to understand the foundations and purposes that animal life acquires during the ritual of sacralization in Candomblecist cosmology: where the animal is acquired, the care and place of its stay in the terreiro before undergoing immolation, who immolates and which species are immolated, the precautions (preceito) taken by the Afro-religious, the instruments and supplies that are part of the ritual, the songs and prayers chanted and finally, after the sacralized animal, how the Orixá and the terreiro eat. And finally, to analyze the debates surrounding the political arguments, mostly Christian, that have tried and are trying to ban this practice on the grounds that it is animal cruelty, as well as to verify the importance of this ritual in the view of religious practitioners and their communication with the spiritual plane.
Avaliação do ciclo de vida de um laminado sintético espalmado de PVC para produção de palmilhas
(Universidade Federal de São Carlos, 2024-04-08) Dutra, Felipe Juliano; Paiva, Jane Maria Faulstich de; https://lattes.cnpq.br/7926832511513537; Moris, Virgínia Aparecida da Silva; https://lattes.cnpq.br/1101036108950133; https://lattes.cnpq.br/6788335333515338
Brazil is currently the fifth largest footwear producer in the world, accounting for 3.9% of global production. In Brazil, there is a tendency to increase the use of synthetic laminates in footwear, mainly due to the variety of colors, prints, thicknesses, and applications with emphasis on PU (polyurethane) and PVC (polyvinyl chloride) laminates. Although PVC is an important alternative in the manufacture of footwear, its use is still questioned from an environmental point of view, mainly due to the emissions throughout the production process, such as dioxins. Therefore, the objective of this work is to present the main environmental hotspots of a synthetic PVC laminate used to make insoles, by carrying out an LCA from cradle to gate, based on a case study. Four impact categories were assessed, based on literature: abiotic depletion, eutrophication, human toxicity, and global warming. The results indicate that the main environmental hotspots occur upstream of the laminate production process for three of the four categories analyzed: production of plasticizer (non-phthalic) for the abiotic depletion and eutrophication categories, and production of emulsion PVC resin (E) for the human toxicity category. The production process of the assessed laminate directly contributes to the potential impacts observed for the global warming category. The possible actions to reduce potential environmental impacts assessed in this study are: the use of vegetable plasticizers and the use of energy from renewable sources, among which, the replacement of plasticizer (non-phthalic) by soybean oil proved to be the most advantageous scenario in the environmental point of view.