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- Vibrações induzidas por peões em escadas metálicasPublication . Andrade, Pedro; Santos, José; Escórcio, Patrícia
- Direct integration methods versus modal superposition method, on predicting staircases vibrationsPublication . Andrade, Pedro; Santos, José; Escórcio, PatríciaThe majority of Finite Element software’s present two different solutions methods to perform time history analysis of the equations of motion due to dynamic (time-varying) loads: Direct Integration and Modal Superposition. This paper aims to assess which method should be employed in the design of modern flexible staircases, to more efficiently predict human induced vibrations. This was verified by estimating vibrations on a real staircase using the two time domain analysis methods and, then, comparing with vibrations experimentally measured. The results indicate that Direct Integration could yield to overestimated responses due to the limited capacity, as the vibration modes increase, of FE numerical models to realistic predict natural frequencies and modal shapes of a real structure. Therefore, Modal Superposition is suggested to be used for design routines, excluding, for the same reason, the vibration modes with higher frequency content. © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Keywords: Modal Superposition; Direct Integration; Duhamel Integral; Human Walking Vibrations; Flexible Staircases. * Corresponding author. Tel.: +351 291 705 197. E-mail address: jmmns@fe.up.pt Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 www.elsevier.com/locate/procedia 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 1st Virtual European Conference on Fracture Direct Integration Methods versus Modal Superposition Method, on Predicting Staircases Vibrations Pedro Andradea , José Santosb,c,*, Patrícia Escórciob a University of Madeira, 9020-105 Funchal, Portugal b University of Madeira, Faculty of Exact Sciences and Engineering, Department of Civil Engineering and Geology, 9020-105 Funchal, Portugal c CONSTRUCT-LABEST, Faculty of Engineering (FEUP), University of Porto, Portugal Abstract The majority of Finite Element software’s present two different solutions methods to perform time history analysis of the equations of motion due to dynamic (time-varying) loads: Direct Integration and Modal Superposition. This paper aims to assess which method should be employed in the design of modern flexible staircases, to more efficiently predict human induced vibrations. This was verified by estimating vibrations on a real staircase using the two time domain analysis methods and, then, comparing with vibrations experimentally measured. The results indicate that Direct Integration could yield to overestimated responses due to the limited capacity, as the vibration modes increase, of FE numerical models to realistic predict natural frequencies and modal shapes of a real structure. Therefore, Modal Superposition is suggested to be used for design routines, excluding, for the same reason, the vibration modes with higher frequency content.
- Using BIM to improve building energy efficiency: a scientometric and systematic reviewPublication . Pereira, Vítor; Santos, José; Leite, Fernanda; Escórcio, PatríciaThe Architecture, Engineering, Construction, and Operations (AECO) sector is responsible for a great pro portion of the global energy consumption and associated environmental impacts. On this front, and from a sustainability improvement perspective, the use of Building Information Modelling (BIM) capabilities could represent an opportunity to improve these impacts in all steps of a building’s life. The main purpose of the current paper is to identify the areas in which BIM technology can or already is playing a role in improving building efficiency, helping AECO sector stakeholders in reducing environmental impacts. In the current paper, the impact of using BIM to enhance the building energy efficiency is explored through a scientometric analysis and a systematic literature review. There is a high interest among the scientific community in these fields, given the recent rise in publications and citation numbers. Moreover, there is a lack of interoperability between BIM and energy analysis tools, a high potential for integrating BIM with other technologies, such as thermography, Geographic Information Systems (GIS) and monitoring, and a very positive impact from the use of BIM in the optimisation of construction solutions which allow energy savings in the AECO sector.
- Numerical methods to predict human induced vibrations on low frequency stairs. Part 2: evaluation by comparing with experimental dataPublication . Andrade, Pedro; Santos, José; Escórcio, PatríciaNowadays, vibration serviceability criteria are becoming the governing factor in the design of most modern staircases, because their increasing susceptibility to human induced vibrations. Although more awareness have been raised to the dynamic design of new staircases, there are still few studies found in the literature that compare the different results of numerical methods for predicting vibrations with experimental data, in order to validate the same. Hence, this paper employs the main existing numerical methods to an actual staircase with known liveness, by comparing the predicted results with the experimental data, to evaluate their accuracy when designing flexible staircases. This paper is Part 2 of a set of two papers. In Part 1, the different numerical methods are presented and details are given of how to apply them. To accomplish this, an in-situ staircase dynamic characterisation and several walking tests are performed. The measured vibrations are initially compared with different proposed acceptable limits to confirm that the vi brations exceed the limits. The different numerical methods are then employed and the predicted results are compared with the experimental results. Lastly, the main findings of this work are discussed together with those of diverse researchers who also applied one of these procedures to estimate vibrations. The results obtained showed that, with two of the numerical procedures applied (footfall force time histories and simplified vibration evaluation), it was possible to effectively predict the vibrations, while with the remaining two (Fourier series walking models and steady-state analysis), in general, overestimated responses were predicted.
- Plano para integração do BIM em diversas disciplinas do curso de engenharia civil da UMaPublication . Escórcio, Patrícia; Santos, JoséApós a introdução do ensino de um software BIM (Autodesk Revit) na UC de Desenho Técnico Assistido por Computador do 1º ano do curso de Engenharia Civil, na Universidade da Madeira, em 2010, verificou-se que o nível de conhecimento BIM dos alunos se situa ao nível do modelador BIM e continua a ser insuficiente face às necessidades das indústrias AECO. Para uma formação mais sólida e completa na área do BIM, é importante estimular o desenvolvimento de competências de trabalho colaborativas e interdisciplinares, promover o conhecimento na área da aplicação de materiais de construção, métodos de construção, projeto de especialidades, gestão de custos e materiais, deteção de conflitos e de uma forma genérica, fomentar a utilização de outras ferramentas BIM, noutras UCs ao longo do curso. Assim, neste trabalho é feita uma análise aos conteúdos programáticos das diferentes UCs do curso de Engenharia Civil para se verificar como e onde podem ser utilizados modelos e softwares BIM. Para tal foi necessário definir previamente um conjunto de competências necessárias para os docentes e um conjunto de competências que se pretende que os alunos atinjam. Deste modo, foi definido um plano de integração BIM para mais de uma dezena de UCs de modo a sensibilizar e motivar os respetivos docentes.
- Utilização de ferramentas BIM na avaliação da eficiência energética dos edifícios: estado da artePublication . Santos, José; Escórcio, Patrícia; Pereira, VítorNa última década as exigências relativas à eficiência energética dos edifícios aumentaram substancialmente. Por sua vez, as ferramentas BIM têm permitido a realização de tarefas de otimização de soluções na fase de conceção que antes eram muito trabalhosas, assim como difíceis de conciliar. Neste artigo faz-se uma revisão bibliográfica sobre a utilização de ferramentas BIM com a finalidade de obter edifícios energeticamente mais eficientes. São identificados e analisados os tópicos mais relevantes sobre o tema, assim como identificadas as ferramentas BIM mais utilizadas. Constata-se que embora haja ainda muitos aspetos a melhorar, já é possível usar as ferramentas BIM para obter edifícios mais eficientes.