ESTiG - Resumos em Proceedings Não Indexados à WoS/Scopus
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Percorrer ESTiG - Resumos em Proceedings Não Indexados à WoS/Scopus por Objetivos de Desenvolvimento Sustentável (ODS) "09:Indústria, Inovação e Infraestruturas"
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- Accurate 3D numerical models for the fire performance on lsf partition walls under different fire scenariosPublication . Piloto, Paulo A.G.; Silva, Renata; Frizzera, Giovanna; Torres, Leonardo; Couto, Carlos; Vila Real, Paulo; Mesquita, Luís M.R.; Lopes, NunoThis study presents the development and validation of advanced 3D numerical models to analyse the fire performance of non-load-bearing Light Steel Frame (LSF) partition walls under different fire scenarios, specifically the standard ISO 834 and HYDROCARBON fire. Medium-scale experimental fire resistance tests from prior research were used for validation, focusing on LSF walls with and without cavity insulation (external composite insulation). Three computational solution methods were compared and used to predict the fire behaviour of LSF walls with a void cavity. The finite element method was employed for transient thermal analysis with temperature-dependent material properties, including adaptations to simulate material degradation such as gypsum board cracking and rock wool melting under HYDROCARBON fire conditions. Hydrocarbon fires reduced fire resistance by an average of 57% compared to ISO 834 fires for cavity-insulated walls, whereas external insulation configurations showed less reduction.
- Acorn pre-drying: implications for the food industryPublication . Farrero, Bernardo; Ribeiro, Luís Frölén; Famiglietti, Antonio; Babo, PedroIn industry, 74% of the energy consumed is used in the form of heat. The food sector is characterised by a high share of processes that rely on industrial heat [1]. However, 90% of this thermal energy currently comes from fossil fuels, and only 9% is supplied by renewable sources [2]. The adoption of solar thermal technologies in the food industry offers multiple benefits that support its viability as an energy alternative to overcome this caveat. Firstly, by relying on a renewable and stable source. Manufacturers can reduce production costs and limit their exposure to the volatility of fossil fuel prices, thereby ensuring greater long-term price stability and predictability [3]. These reductions in energy costs may also be reflected in lower prices for the end consumer. Solar-assisted dehydration enables a decrease in moisture content, thereby limiting microbial growth and food spoilage [3]. In this regard, Solar Heat for Industrial Processes (SHIP) may also address food security concerns as storage losses are estimated to reach up to 20%, posing a critical challenge to food security [4]. The installation of in-situ pre-dehydration systems near harvesting zones provides clear benefits for energy efficiency and product quality. The Iberian Peninsula, notably, benefits from very high solar radiation, with many clear-sky days and extended sunlight periods, making it particularly suitable for solar-based pre-dehydration systems. By lowering produce weight and moisture before transportation, these systems decrease fossil energy demand during both industrial drying and large-scale transport [5]. This approach reduces the final product cost, as demonstrated by an in-situ solar dryer used for acorns in Alentejo holm oak groves. The passive, indirect mobile dryer, fitted with hanging bags, reduces acorn moisture content by 15% after 72 hours of drying, delays fruit spoilage, and cuts large-scale industrial heat input [6,4]. Thermal energy data from a factory case at Landratech, an acorn food producer involved in the MEDACORNET project, indicate that 15% in-situ pre-dehydration cuts thermal energy use by 52% during both initial and final drying stages of acorn flour manufacture [3]. This combined method lowers fossil fuel use, reduces losses, improves energy efficiency, and supports sustainability in the food processing sector.
- Adoption of wearables: a UTAUT2 perspectivePublication . Lopes, Isabel Lopes; Oliveira, PedroThis research sought to understand the adoption of Wearable devices, analyzing aspects such as demographic profiles, experiences with technology and personal perceptions. An adaptation of the UTAUT2 model was made, obtaining responses from university students and frequent internet users through a survey using the Likert scale questions was administered to 96 participants. Based on the analysis, there was a tendency for higher acceptance among younger people, those with higher levels of education and greater technological proficiency among men and more qualified individuals. The Smartwatch stood out among the devices, followed by the Fitness Bracelet and the Smart Ring. A variation in social influence was observed according to the type of apparatus. Unexpectedly, social influence has not proven to be as crucial in the acceptance of wearable devices as initially thought. The results show a trend towards the adoption of these devices, while also warning of challenges linked to the perceived value and price of products.
- Austenitic hollow stainless steel beams at elevated temperatures: experimental and numerical validationPublication . Piloto, Paulo A.G.; Mesquita, Luís M.R.; Cruz, Áureo; Lopes, Nuno; Arrais, Flávio; Vila Real, Paulo
- BIMandmodular construction- a review of the potential uses in design phasePublication . Carvalho, Márcio; Oliveira, Rui; Rodrigues, HugoModular construction has been gaining increasing prominence in the construction industry, driven by the growing urbanization and the need to explore new construction systems in response to frequent labor shortages, resource optimization, and a lack of quality control in construction. The set of very specific and deeply rooted characteristics of traditional construction, coupled with the costs associated with modular construction, pose a barrier to opting for modular construction systems, a situation that needs demystification. This type of construction offers numerous advantages related to production, quality, speed, comfort, and a positive contribution to sustainability, but it contains unique characteristics that need consolidation to streamline processes and enhance simplicity in usage.This paper examines the integration of Building Information Modeling (BIM) in modular construction during the design phase, in addition to identify the technologies and methods currently using, as DfMA (Design for Manufacture and Assembly), ML (Machine Learning), CDE (Common Data Environment) and others, trying integrate this concepts in the design phase of this construction system. Collaboration among construction professionals and data integration throughout all project stages are crucial elements for the successful combination of BIM and modular construction. This proposed approach introduces various current tools based on the BIM methodology for the specific development of projects for this type of construction system, relying on literature review and input from industry experts. Additionally, the paper identifies promising research areas and opportunities to further refine this integration, aiming to improve efficiency and quality in the construction industry
- Caracterização mecânica de provetes de granito sujeitos a temperaturas elevadasPublication . Ferreira, Débora; Fontes, Luís; Vanconcelos, Graça; Oliveira, Edna; Mesquita, Luís M.R.O aumento da temperatura média na superfície da terra pode trazer diversas e complexas consequências ao meio ambiente, além de danos irreversíveis para a humanidade. Um dos efeitos diretos é o aumento do número de incêndios rurais, que possuem um elevado potencial de destruição não só para a fauna e a flora do local, mas também para o património vernáculo constituído. Estas construções rurais merecem ser cuidadosamente salvaguardadas pois constituem a união entre o património natural e o património cultural. As construções vernáculas são maioritariamente compostas por alvenaria de pedra de junta seca, alvenaria de pedra com argamassa de cal ou alvenaria de pedra com argamassa à base de terra. Os efeitos causados pelos incêndios nestas construções resultam na sua elevada destruição bem como na destruição do seu legado histórico.
- Estudo paramétrico das características das ações do vento para o dimensionamento de torres tubulares metálicas segundo os eurocódigosPublication . Carvalho, Márcio; Oliveira, Rui; Rodrigues, Hugo; Rodrigues, Fernanda; Silva, TiagoO comportamento estrutural de torres metálicas é maioritariamente influenciado pela ação do vento, sendo a principal carga externa atuante para esse tipo de estrutura. Por isso, compreender e entender como as diferentes condições do vento afetam esse tipo de estrutura é essencial. Ainvestigação realizada envolve modelação e análise de resultados obtidos na realização de um estudo paramétrico da influência de diferentes condições de vento sobre uma torre tubular metálica, dimensionada de acordo com os eurocódigos 1 e 3. O objetivo é observar e analisar a influência da variação de alguns parâmetros principais do vento e a resposta estrutural de uma torre padrão para essas alterações. Para tal, foram consideradas diferentes condições do vento, contempladas pelo eurocódigo 1, nomeadamente a zona de vento, rugosidade do terreno, categoria do terreno e orografia. Foram analisados o comportamento global da estrutura, com foco na obtenção de alguns parâmetros da torre para as diferentes condições, como deslocamento no topo, deflexão e rácio máximo entre tensão atuante e tensão resistente. Também foram analisados as solicitações induzidas pelo vento para cada condição, para obtenção de alguns parâmetros da interação entre o vento e a estrutura, como o coeficiente estrutural (cscd), que tem em conta o efeito da não simultaneidade na ocorrência de pressões de pico sobre a superfície em conjunto com o efeito das vibrações da estrutura devidas à turbulência. Os resultados permitem analisar o impacto das diferentes condições do vento para o dimensionamento de torres tubulares, contribuindo para o desenvolvimento e fomentação de diretrizes de projeto mais robustas para esse tipo de estrutura.
- (In)capacidade para InovarPublication . Praça, Lídia GalvãoEste estudo pretende analisar os fatores considerados mais importantes pelas empresas portuguesas na sua decisão de iniciar ou executar atividades de inovação, bem como a sua evolução ao longo do tempo. Identifica quais têm sido os principais obstáculos à inovação enfrentados pelas empresas portuguesas, inovadoras ou não inovadoras. Apresenta os principais fatores que dificultaram a atividade de inovação, de acordo com o setor de atividade (CAE), localização geográfica e dimensão da empresa, expressa por escalão de pessoal. Apresenta ainda, as razões para não inovar, apontadas pelas empresas não inovadoras, bem como as razões para não desenvolverem mais atividades de inovação, no caso das empresas consideradas inovadoras. A análise tem como base, as estatísticas produzidas pelos Inquéritos Comunitários à Inovação (CIS) e para o período compreendido entre 2012 a 2020. O estudo permite concluir que a atividade da empresa, a região onde opera e a dimensão têm influência na tomada de decisão e capacidade de inovar.
- Modelling techniques for the fire performance of empty cavities in LSF wallsPublication . Piloto, Paulo A.G.; Gomes, Stephan; Torres, Leonardo; Couto, Carlos; Vila Real, PauloThree different solution models were used to compare the fire performance of LSF walls with void cavities. The first solution method considers the air-structure interaction in the cavity region. The second solution method considers the existence of interface elements for the radiation heat transfer in the cavity region allowing the bulk temperature prediction. The third solution method considers the convection and radiation in the cavity region with a prescribed bulk temperature from experiments (hybrid). Solution methods 1 and 3 give a smaller root mean square error (RMSE), when compared with solution method 2. Solution method 3 gives a better approximation because can capture the main fire events during fire testing, such as the cracks and fall off.
- A new proposal for estimating the temperatures on the steel deck components of composite slabs under firePublication . Balsa, Carlos; Lima, Lídia; Piloto, Paulo A.G.This work aims to improve the estimation of the temperatures on the steel deck under fire. An accurate estimation of these temperatures is crucial to determine the load-bearing capacity (R) of the slab. An analytical method, alternative to the simplified method provided by Eurocode 4, that enables temperature estimation on the steel deck components (web, lower and upper flange), is derived from the numerical results, obtained with a three-dimensional computational model. This new proposal considers the effect of the concrete thickness ℎ1, enables to obtain unbiased temperatures and, contrary to the Eurocode 4 proposal, fits very well the numerical results.