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Railway track support condition assessment
AbstractA novel methodology to evaluate railway track support conditions is currently being developed. This methodology is based on modal analysis of the multi-element system composed by the railway infrastructure and an instrumented railway vehicle. It belongs to the group of vibration-based structural damage identification methods and is focused on observing the characteristic frequencies of this multi-element system, which can be related with changes in the physical properties of the railway infrastructure. As opposed to other vehicle-based track monitoring methods, the proposed methodology should enable condition assessment of the railway infrastructure subgrade, an element that is often neglected during railway monitoring operations. Since this methodology is vehicle-based, it can be used to assess the entire extension of a railway infrastructure to gather data regarding the support conditions of the track. It can also assess the evolution of track support conditions over time by comparing different rides over the same railway stretch. An important aspect of this methodology that still lacks validation is the topic of characterizing track support conditions of a railway infrastructure through its natural frequencies. The suitability of the theoretical model behind this methodology is another aspect that needs to be assessed. Numerical simulations tests using the multibody simulation software Simpack® are currently being performed to address both topics. This paper describes some of the simulations performed in this context, including a description of the numerical models used. The obtained results support the selected theoretical model and the overall validity of the proposed methodology.
Ano: 2023
Autor(es): Mendes, J.; Calçada, R.; Ribeiro, D.; Fortunato, E.; Morais, J.
Revista: Engineering Failure Analysis
Editor: ELSEVIER
Volume:
Volume 152, October 2023, 107483.
Keywords: Early detection; Natural degradation; Degradation; Physical properties analysis; Natural materials; Railway track; Mechanical engineering
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Reabilitação térmica em habitação social. Redução do desconforto térmico
No âmbito da reabilitação de um bairro de habitação social construído nos anos 80, constituído por 27 blocos de frações, foi desenvolvido um estudo de investigação com vista à avaliação das condições de conforto térmico no interior de várias frações constituintes do referido bairro, assim como da perceçãotérmica dos seus ocupantes, antes e após a intervenção de reabilitação.
Ano: 2023
Autor(es): Matias, L.
Revista: Construção Magazine
Editor: Engenho e Média, Lda
Volume:
Nº 118.
Keywords: reabilitação; no interior; conforto térmico; avaliação; Anos 80; habitação social
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Recommendation of RILEM TC 271-ASC: New accelerated test procedure for the assessment of resistance of natural stone and fired-clay brick units against salt crystallization
This recommendation is devoted to testing the resistance of natural stone and fired-clay brickunits against salt crystallization. The procedure was developed by the RILEM TC 271-ASC to evaluate thedurability of porous building materials against salt crystallization through a laboratory method thatallows for accelerated testing without compromising the reliability of the results. The new procedure isdesigned to replicate salt damage caused by crystallization near the surface of materials as a result ofcapillary transport and evaporation. A new approach is proposed that considers the presence of two stages inthe salt crystallization test. In the first, the accumulation stage, salts gradually accumulate on or near thesurface of the material due to evaporation. In the second, the propagation stage, damage initiates anddevelops due to changes in moisture content and relative humidity that trigger salt dissolution andcrystallization cycles. To achieve this, two types of salt were tested, namely sodium chloride and sodiumsulphate, with each salt tested separately. A methodology for assessing the salt-induced damage isproposed, which includes visual and photographical observations and measurement of material loss. The procedure has been preliminarily validated in round robin tests.
Ano: 2023
Número Páginas:
12p..
Autor(es): Veiga, M. R.; Gonçalves, T. D.; Lubelli, B.
Revista: Materials and Structures
Editor: Spinger
Volume:
56.
Keywords: Sodium chloride; Sodium sulfate; RILEM TC 271-ASC; Salt crystallization test; Recommendation
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Renovadas soluções residenciais para as pessoas idosas
Depois de um conjunto de notas introdutórias e de apresentação ao estudo global intitulado Programa de Habitação Adaptável Intergeracional desenvolvido num quadro Cooperativo e a Custos Controlados (PHAI3C), desenvolvem-se, primeiro, alguns aspetos associados às alternativas tipológicas residenciais à disposição dos idosos europeus, abordando-se, em seguida, a relação entre as escalas do habitar e os novos tipos habitacionais ligados aos idosos e rematando-se o texto com uma reflexão sobre a relação entre novas escolhas residenciais e novas formas de habitar.Nesta última temática desenvolvem-se, sequencialmente, quatro temas: a habitação dos idosos
Ano: 2023
Número Páginas:
26p..
Autor(es): Baptista Coelho, A.
Revista: Infohabitar
Editor: Associação Portuguesa para a Promoção da Qualidade Habitacional - GHabitar APPQH
Volume:
Ano XIX, n.º 868.
Keywords: Intergeracionalidade; Habitação para idosos; Habitação intergeracional; Habitação
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Road Pavement, Road Pollution, and Sustainability under Climate Change Increased Temperature
This paper presents a multidisciplinary approach to understand the impacts of temperatureincrease on the retention of particulate pollutants, such as heavy metals and microplastics, by the roadpavement material. A soil with a particle size distribution similar to road dust was selected. A WheelTracking device was used to assess the permanent deformation behavior of prismatic specimens andthe retention of the dust, at controlled temperatures of 40 C and 60 C, likely to occur on pavementin the future. The soil representing road pollutants was placed at the top of the slabs prior to theWheel Tracking Test (WTT), based on the European Standard EN 12697-22:2020. After the WTT, twocommon methods were used, in order to evaluate the soil retention (pollution accumulation) onroad pavement. The results confirm that the viscoelastic behavior of bituminous mixtures underincreased temperatures can contribute to particle retention at the pavement. Future studies areneeded to understand the phenomena, the retention characteristics by different bituminous mixtures,and the efficiency of pollutants capture. The work opens the opportunity to develop innovative roadpavement bituminous mixtures that can reduce the discharge of road particulate pollutants, and haveincreased resilience and sustainability in extreme weather conditions.
Ano: 2023
Número Páginas:
14p.
Autor(es): Barbosa, A. E.; Fontul, S.; Freire, A. C.; Simões, A.
Revista: Applied Sciences
Editor: MDPI
Volume:
Volume 13.
Keywords: sustainable development; road runoff pollution; road pavement materials; new methodologies; heat effects; bituminous mixtures; climate change
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Rock engineering design in tomorrow
he current first generation of Eurocodes is a suite of ten Euro-pean standards for the design of buildings and civil engineeringworks, whose implementation started in 2010. EN 1990 sets thebasis of structural design, with the other Eurocodes dealingwith different materials and specific aspects of design. Geo-technical aspects of design are covered by EN 1997
Ano: 2023
Número Páginas:
469-490pp..
Autor(es): Lamas, L.; Burbaum, U.; Estaire, J.; Harrison, J.; Nuijten, G.; Pereira, R.
Revista: Geomechanics and Tunnelling
Editor: Ernst & Sohn
Volume:
16(5).
Keywords: Design; Rock engineering; Geotechnical structures; Eurocode
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SARClust
Interferometric Synthetic Aperture Radar (InSAR) has proved its efficiency for displacementmonitoring in urban areas. However, the large volume of data generated by this technology turnsthe retrieval of information useful for structure monitoring into a big data problem. In this study, anew tool (SARClust) to analyze InSAR displacement time series is proposed. The tool performs theclustering of persistent scatterers (PSs) based on dissimilarities between their displacement time seriesevaluated through dynamic time warping. This strategy leads to the formation of clusters containingPSs with similar displacements, which can be analyzed together, reducing data dimensionality, andfacilitating the identification of displacement patterns potentially related to structural damage. Aproof of concept was performed for downtown Lisbon, Portugal, where ten distinct displacementpatterns were identified. A relationship between clusters presenting centimeter-level displacementsand buildings located on steep slopes was observed. The results were validated through visualinspections and comparison with another tool for time series analysis. Agreement was found inboth cases. The innovation in this study is the attention brought to SARClust
Ano: 2023
Número Páginas:
19p..
Autor(es): Roque, D.; Falcão, A. P.; D. Perissin; Amado, C; Lemos, J. V.; Fonseca, A. M.
Revista: Sustainability
Editor: MDPI
Volume:
15.
Keywords: Dynamic time warping; Hierarchical clustering; RADAR interpretation; InSAR; Structure monitoring
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Shared e-scooters and the promotion of equity across urban public spaces - A case study in Braga, Portugal
Shared e-scooters were introduced in urban public spaces as a way to promote a modal shift from cars in short-distance trips, as well as to improve sustainability, resilience, and equity in urban transport. However, the expansion of shared e-scooter services in 2019 proved that this mode of transport, without integrated planning strategies, can bring some problems to cities, which are related to the illegal parking of e-scooters, an increase in head injuries, and the lack of population diversity among users. Regarding the latest, this research work aims at conducting a case study in the city of Braga, Portugal to reveal who the actual and potential users of shared e-scooters are and how their socioeconomic profile (e.g., gender, age, income range, literacy, occupation) and usage patterns related to the ones found in other cities. For this, a revealed preference survey was deployed on the case study site, and the respondents
Ano: 2023
Autor(es): Dias, G.; Ribeiro , P; Arsenio, E.
Revista: Applied Sciences
Editor: MDPI
Volume:
13 (6).
Keywords: Sustainable mobility; Equity in micromobility; Shared e-scooters; Micromobility
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SILUC
A identificação de todas as disposições legais e regulamentares que se aplicam a cada operação urbanística concreta é um desafio. Essas disposições encontram-se dispersas em mais de dois milhares de diplomas legais e regulamentares, sucessivamente publicados ao longo do tempo. Ciente desta dificuldade, há mais de cinco décadas o Estado assumiu o compromisso legal de sistematizar e divulgar periodicamente uma relação das normas técnicas da construção, o que foi reafirmado em 1999 no Regime Jurídico da Urbanização e Edificação.Com vista a contribuir para cumprir esse compromisso, foi criado o «SILUC
Ano: 2023
Número Páginas:
10-14pp..
Autor(es): Branco Pedro, J.; Cabaço, A.; Vicente, M.; Campos, V.
Revista: Construção Magazine. Revista Técnico-Científica Engenharia Civil
Editor: Engenho e Média, Lda
Volume:
nº 115.
Keywords: operação urbanística; disposições legais e regulamentares; SILUC
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SILUC
A identificação de todas as disposições legais e regulamentares que se aplicam a cada operação urbanística concreta é um desafio. Essas disposições encontram-se dispersas em mais de dois milhares de diplomas legais e regulamentares, sucessivamente publicados ao longo do tempo. Ciente desta dificuldade, há mais de cinco décadas, o Estado assumiu o compromisso legal de sistematizar e divulgar periodicamente uma relação das normas técnicas da construção, o que foi reafirmado em 1999 no Regime Jurídico da Urbanização e Edificação.Com vista a contribuir para cumprir esse compromisso, foi criado o «SILUC
Ano: 2023
Número Páginas:
10-14pp..
Autor(es): Branco Pedro, J.; Cabaço, A.; Vicente, M.; Campos, V.
Revista: Revista Técnico-Científica Engenharia Civil.
Editor: Construção Magazine.
Volume:
nº 115.
Keywords: Legislação de Urbanismo e Construção (LUC).; Portugal; Plataforma eletrónica oficial; SILUC
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