Artigos de Revista
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Dynamics of CO2, CH4, and N2O in Ria Formosa coastal lagoon (southwestern Iberia) and export to the Gulf of Cadiz
A first characterization of greenhouse gases had been carried out to study their role and impact in a productive transitional coastal system of the southern Portugal
Ano: 2024
Número Páginas:
17p..
Autor(es): Cravo, A.; Rodrigues, M.; Forja, J.; Ortega, T.; Correia, C.; Sierra, A.
Revista: Science of the Total Environment
Editor: Elsevier
Volume:
(906)167094.
Keywords: Coastal lagoon; Ria Formosa; Gas mass transport; Water - atmosphere fluxes; Greenhouse gases
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Global and local geometrical imperfections of pultruded GFRP profiles based on a modal approach
ABSTRACT - The ultimate capacity of pultruded glass fibre reinforced polymer (pGFRP) profiles depends significantly on geometrical imperfections (GIs), given their sensitivity to buckling phenomena arising from both thin walls and low elastic moduli. However, GIs are not yet comprehensively addressed in design guidance. This paper proposes a new approach to characterize the initial GIs of pGFRP profiles based on a modal approach. Given the lack of comprehensive knowledge in this area, this study presents a highly accurate and robust methodology to measure GIs and dimensional deviations (DDs) in pGFRP profiles using a 3D contact coordinate measurement machine (CMM). The modal approach encompasses the measurement of dimensional parameters and a point cloud transformation that enables the assessment of GIs associated with pure buckling modes of pGFRP profiles. This procedure allows the quantification of three types of global GIs associated to (i) minor-axis (weak axis), (ii) major-axis (strong axis) bending, and (iii) twist. Additionally, the procedure also includes the assessment of local GIs, considering the wall (plate-like) imperfections. The separation of GIs into these four types (shape and amplitude) is of major relevance as its paves the way to the development of analytical design formulas for the strength prediction of pGFRP members. The approach described in this paper also serves two important purposes: (i) the statistical analysis of DDs and GIs of pGFRP members, and (ii) the identification of distinct shapes and amplitudes of GIs that form the basis for reliable design considerations of pGFRP members.
Ano: 2024
Número Páginas:
18p..
Autor(es): Silvestre, N.; Correia, J.; Pinheiro, A.; Ribeiro, A.; Lages Martins, L.; Lazzari, J.
Revista: Construction and Building Materials
Editor: ELSEVIER
Volume:
412 (2024) 134813.
Keywords: Modal decomposition; Geometrical imperfections; Dimensional deviation; 3D contact measurements; Pultruded profiles; Glass fibre reinforced polymer (GFRP)
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20th Century Mortars: Physical and Mechanical Properties from Awarded Buildings in Lisbon (Portugal)
This paper addresses the study of renders and plasters
Ano: 2023
Número Páginas:
26p..
Autor(es): Mirão, J.; Veiga, M. R.; Santos Silva, A.; Almeida, L.
Revista: Buildings
Editor: MDPI
Volume:
13.
Keywords: Compatibility; 20th century; Portland cement; Lime
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20th Century Mortars: Physical and Mechanical Properties from Awarded Buildings in Lisbon (Portugal)
This paper addresses the study of renders and plasters
Ano: 2023
Autor(es): Mirão, J.; Veiga, M. R.; Santos Silva, A.; Almeida, L.
Revista: buildings
Editor: MDPI
Volume:
13.
Keywords: compatibility; 20th century; Portland cement; lime
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2DH modelling and mapping of surfbeat-driven flooding in the shadow of a jettied tidal inlet
Near estuaries and harbours, submerged shoals and defence structures impact the exposure to overtopping. These features may be accounted for in two-dimensional horizontal (2DH) numerical models, either based on phase resolving or phase-average solvers for wave propagation. In between, surfbeat solvers, such as in XBeach, combine an affordable computational cost with the ability to generate and propagate the longer infragravity (IG) waves. However, surfzone wave characteristics and the overtopping exposure modelled with XBeach are sensi tive to settings such as the shape of the forcing wave spectra and the numerical scheme for wave propagation. The present paper explores this sensitivity and assesses the performance of different inundation models built with the 2DH surfbeat solver of XBeach. These models were forced with downscaled water levels and directional wave spectra and the results fuelled a discussion bounded by data collected downdrift of the entrance to the harbour of Figueira da Foz (Portugal). The original second-order upwind scheme, which propagates short-waves with a lower numerical diffusion improved the model performance in terms of long-wave height, and an unconventional breaking criterion better represented the cross-shore distribution of short-wave height near the shore. A cali brated model was validated through the hindcast of an overtopping event observed under moderate swell forcing, and was used to map the overtopping exposure during a hypothetical combination of an energetic swell with a water level having a return period of ~70 years. Compared to the default wave spectra shape and model settings, using an appropriate representation of the short-wave directional spectrum at the open boundary was necessary to reproduce the observed overtopping extent. Refining the cross-shore resolution of the model helped to better represent the observed inundation extents, as also did the reduction of the friction coefficient. Addi tional phase-resolving simulations in 1DH overestimated IG wave energy and produced higher and more frequent overtopping discharges. The differences with the calibrated 2DH surfbeat model increased with the proximity of the inlet and with short-wave height and angle of incidence. Overall, required calibration steps were provided. They aim at making 2DH XBeach surfbeat a credible tool for 1) predicting short and IG wave characteristics up to the shoreline, as well as for 2) providing first estimates of exposure to overtopping in areas with shallow and alongshore-irregular morphologies.
Ano: 2023
Número Páginas:
1-21pp.
Autor(es): Freire, P.; Baptista, P.; Silva, P. A.; Henriques, M.; Azevedo, A.; Oliveira , F.; Fortunato, A. B.; Nahon, A.
Revista: Coastal Engineering
Editor: Elsevier B.V.
Volume:
184.
Keywords: XBeach; Infragravity waves; Ebb-tidal delta; Intermediate beach; Overtopping
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A ciência é do povo? Citizen science, reflexões sobre o conceito e os processos científicos da produção da verdade num mundo cada vez mais inseguro
À medida que as ameaças ambientais se multiplicam à escala global exige-se uma mais apurada reflexividade sobre as práticas humanas, as formas de utilização dos territórios e seus recursos e a capacidade de previsão e resposta quanto a eventos ambientais extremos, socialmente disruptivos. Ora, é esta capacidade de previsão que a ciência experimenta em uma dimensão cada vez menos segura, entrando em crise os modelos causais e a pertinência do conhecimento empírico baseado em observações do passado, pois o futuro torna-se progressivamente mais incerto e ameaçador. Incerteza e ameaça que se antecipam em cada crise, sob a manifestação dos riscos ambientais [1]. Algumas destas manifestações tornam-se indetetáveis para os sentidos humanos, a não ser pela própria visibilidade das consequências. As comunidades humanas encontram-se, assim, cada vez mais dependentes da análise e do discurso da ciência para perceberem (mesmo que na impossibilidade de compreenderem com exatidão os mecanismos de exposição) os riscos a que estão expostas. A humanidade parece, pois, acossada numa estrutura medieval do medo, o medo do invisível, na emergência de um novo tipo de sociedade colonizada pelo medo e que dá lugar a todas as derivas políticas [2]....
Ano: 2023
Autor(es): Craveiro, J.
Revista: Plataforma Barómetro Social
Editor: Instituto de Sociologia da Universidade do Porto
Keywords: Citizen Science.; Participação; Riscos ambientais
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A comprehensive performance assessment system for diagnosis and decision-support to improve water and energy efficiency and its demonstration in Portuguese collective irrigation systems.
In regions with a strong seasonal or interannual asymmetry in the distribution of precipitation and higher frequency of droughts, collective irrigation systems are vital infrastructures for agricultural activity. Although operating for decades, several systems have ageing infrastructures, with relevant water losses and pumping energy inefficiencies. Consequently, the systems are not adequately designed or operated to meet current and future water demand. Therefore, rehabilitation to improve water and energy efficiency while ensuring infrastructure, economic sustainability and service quality is crucial. In this sense, comprehensive approaches using performance assessment to support the planning process or benchmarking between water users associations play an essential role in improving efficiency in collective irrigation systems.
Ano: 2023
Número Páginas:
15p..
Autor(es): Alegre, H.; Cordeiro, D.; Arranja, C.; Moreira, M.; Beceiro, P.; Loureiro, D.
Revista: Agricultural Water Management
Editor: Elsevier
Volume:
Vol- 275.
Keywords: Water Users Association; Water and energy efficiency; Performance assessment system; Decision support; Diagnosis; Collective irrigation systems
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A European and Brazilian cross-national investigation into the Portuguese translation of soundscape perceptual attributes within the SATP project
This paper presents a cross-national investigation into the soundscape perceptual attributes translation from English into European and Brazilian Portuguese. It is a study within the scope of a larger project
Ano: 2023
Autor(es): Ribeiro, L. C.; Alves, S.; Carvalho, M. L. U.; Michalski, R.; Antunes S.
Revista: Applied Acoustics
Editor: Elsevier
Volume:
Vol. 211.
Keywords: ISO/TS 12913-2:2018; Translation Cross-national; Soundscape attributes
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A RANS-based Numerical Model to Simulate Overtopping-type Wave Energy Converters Integrated into Breakwaters
This study aims to validate a numerical model based on Reynolds-averaged Navier
Ano: 2023
Número Páginas:
420
Autor(es): Teixeira, P.; Didier, E.
Revista: International Journal of Offshore and Polar Engineering
Editor: IJOPE
Volume:
Vol 33 Nº 4.
Keywords: Turbulence models; Numerical wave flume; RANS; Wave energy; Overtopping wave energy converter
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Aerodynamic characterization of the 516 Arouca Pedestrian suspension Bridge over the Paiva River
Given the 516 Arouca pedestrian suspension bridge
Ano: 2023
Número Páginas:
18 pp.
Autor(es): Marques da Silva, F.
Revista: Wind
Editor: MDPI
Volume:
3.
DOI:
10.3390/wind3010006
Keywords: wind tunnel; wind loading; suspended bridges
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