Artigos de Revista
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Energy rate balance applied to coastal engineering problems by using RANS-VoF models in numerical wave flumes 
Nowadays, the use of RANS-based models for simulating numerical wave flumes and studying coastal engineering structures is common and allows investigating accurately phenomena that occur in current/wavestructure interactions. Comprehension of energy transformations in these processes can support designers tooptimize the system. In this study, a methodology to evaluate the terms of the energy rate balance in coastalengineering problems is developed. The methodology is applied to the propagation of regular waves in numericalwave flumes, onshore oscillating water column wave energy converter integrated into a vertical breakwater, andtwo types of rubble-mound breakwaters. The direct determination of the energy rate due to viscous and urbulencelosses and the porous resistance in rubble-mound breakwaters are carried out by time integration insidethe computational domain. Besides, the reflected and transmitted energy rates in the flume are calculated bymeans of this methodology, instead of the standard gauge methods, commonly used in physical and numericalflumes. Complementary, studies may be carried out for random incident waves and the methodology can beapplied to 3D wave tanks.
Ano: 2025
Autor(es): Teixeira, P.; Didier, E.
Revista: Ocean Engineering
Editor: Elsevier
Keywords: Rubble-mound breakwater; Oscillating water column wave energy converter; Energy rate balance; Coastal engineering; Numerical wave flume; RANS models
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An assessment of 3D scanning methods in physical models
The evaluation of damage progression caused by wave action on physical models of rubble-mound breakwaters can be accomplished through two types of methods: quantifying the movements and falls of the resistant armor elements by visual inspection (the traditional, classical method) or determining the eroded volumes and depths between consecutive surveys of armor layers using sensors and photogrammetric methods (3D scanning methods). Of the latter, one may use techniques such as the so-called "Kinect", "Photogrammetry" and "LiDAR". The end-product of these techniques is, among others, point clouds, which allow obtaining three-dimensional surface models. In this paper, four of the latter techniques (3D scanning methods) are briefly described, and a comparison is made between them regarding their usability in current tests, their advantages and disadvantages, among themselves for a study case of the physical 3D model of the Ericeira breakwater. In evaluating survey quality across the four methods, RMSE (root mean square error) was employed to align obtained point clouds with ground control points (GCP). Notably, Photogrammetry, Kinect, and Azure techniques showed excellent RMSE values. Conversely, the LiDAR-derived-method cloud, using a smartphone with LiDAR sensor and 3dScanner app, fails to yield acceptable and accurate results for the research objectives of this paper.
Ano: 2024
Autor(es): Capitão, R.; Lemos, R.; Fortes, C. J. E. M.; Jónatas, R.
Editor: COSE
Keywords: 3D scans; Reconstruction Techniques; Damage Progression; Breakwater; Physical Modelling
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Analytical and numerical modelling of wave dissipation over rigid and flexible vegetation in a flume: Drag coefficient calibration
Data of wave dissipation over vegetation fields was collected from laboratory flume experiments, fordifferent vegetation and wave conditions. An analytical model and a numerical model are applied to estimatethe wave dissipation obtained in the experiments, through the calibration of the bulk drag coefficient (CD).Results and conclusions will analyse and compare each model behaviour and obtained CD values.
Ano: 2024
Autor(es): Reis, R.; Fortes, C. J. E. M.; Suzuki , T.
Editor: IARH EUROPE CONGRESS
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Deep Neural Network Enhanced Early Warning System for Ports Operations
Downtime of port terminals results in large economic losses and has a major impact on the overallcompetitiveness of ports. EarlyWarning Systems (EWS) are an effective tool to reduce ports
Ano: 2024
Autor(es): Pinheiro, L.; Fortes, C. J. E. M.; Gomes, A.
Editor: IARH EUROPE CONGRESS
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Development of a Bayesian network-based early warning system for storm-driven coastal erosion
Coastal hazards such as flooding and erosion can cause large economic and human losses. Under this threat, early warning systems can be very cost-effective solutions for disaster preparation. The goal of this study was to develop, test, and implement an operational coastal erosion early warning system supported by a particular method of machine learning. Thus, the system combines Bayesian Networks, and state-of-the-art numerical models, such as XBeach and SWAN, to predict storm erosion impacts in urbanized areas. This system was developed in two phases. In the development phase, all information required to apply the machine learning method was generated including the definition of hundreds of oceanic synthetic storms, modeling of the erosion caused by these storms, and characterization of the impact levels according to a newly defined eerosion iimpact index. This adimensional index relates the distance from the edge of the dune/beach scarp to buildings and the height of that scarp. Finally, a Bayesian Network that acted as a surrogate of the previously generated information was built. After the training of the network, the conditional probability tables were created. These tables constituted the ground knowledge to make the predictions in the second phase. This methodology was validated (1) by comparing 6-h predictions obtained with the Bayesian Network and with process-based models, the latest considered as the benchmark, and (2) by assessing the predictive skills of the Bayesian Network through the unbiased iterative k-fold cross-validation procedure. Regarding the first comparison, the analysis considered the entire duration of three large storms whose return periods were 10, 16, and 25 years, and it was observed that the Bayesian Network correctly predicted between 64% and 72% of the impacts during the course of the storms, depending on the area analyzed. Importantly, this method was also able to identify when the hazardous conditions disappeared after predicting potential consequences. Regarding the Regarding the second validation approach, second validation approach, the k-fold cross-validation procedure was applied to the peak of a set of varying storms and it demonstrated that the predictive skills were maximized (63%
Ano: 2024
Número Páginas:
1-15pp.
Autor(es): Garzon, J.L.; Ferreira, Ó.; PLOMARITIS, T.A.; Zózimo, A. C.; Fortes, C. J. E. M.; Pinheiro, L.
Revista: Coastal Engineering
Editor: Elsevier
Volume:
Vol 189 (104460).
Keywords: HIDRALERTA; Sandy beaches; Bayesian networks; Numerical modeling; Prediction system
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Development of a Bayesian network-based early warning system for storm-driven coastal erosion
Coastal hazards such as flooding and erosion can cause large economic and human losses. Under this threat, early warning systems can be very cost-effective solutions for disaster preparation. The goal of this study was todevelop, test, and implement an operational coastal erosion early warning system supported by a particularmethod of machine learning. Thus, the system combines Bayesian Networks, and state-of-the-art numericalmodels, such as XBeach and SWAN, to predict storm erosion impacts in urbanized areas. This system wasdeveloped in two phases. In the development phase, all information required to apply the machine learningmethod was generated including the definition of hundreds of oceanic synthetic storms, modeling of the erosioncaused by these storms, and characterization of the impact levels according to a newly defined eerosion iimpactindex. This adimensional index relates the distance from the edge of the dune/beach scarp to buildings and theheight of that scarp. Finally, a Bayesian Network that acted as a surrogate of the previously generated informationwas built. After the training of the network, the conditional probability tables were created. These tablesconstituted the ground knowledge to make the predictions in the second phase. This methodology was validated(1) by comparing 6-h predictions obtained with the Bayesian Network and with process-based models, the latestconsidered as the benchmark, and (2) by assessing the predictive skills of the Bayesian Network through theunbiased iterative k-fold cross-validation procedure. Regarding the first comparison, the analysis considered theentire duration of three large storms whose return periods were 10, 16, and 25 years, and it was observed that theBayesian Network correctly predicted between 64% and 72% of the impacts during the course of the storms,depending on the area analyzed. Importantly, this method was also able to identify when the hazardous conditionsdisappeared after predicting potential consequences. Regarding the Regarding the second validationapproach, second validation approach, the k-fold cross-validation procedure was applied to the peak of a set ofvarying storms and it demonstrated that the predictive skills were maximized (63%
Ano: 2024
Autor(es): Garzon, J.L.; Ferreira, O.; PLOMARITIS, T.A.; Zózimo, A. C.; Fortes, C. J. E. M.; Pinheiro, L.
Revista: Coastal Engineering
Editor: Elsevier
Volume:
189 (2024) 104460.
Keywords: HIDRALERTA; Sandy beaches; Bayesian networks; Numerical modeling; Prediction system
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Experimental investigation of wave severity and mooring pretension on the operability of a moored tanker in a port terminal
This paper investigates the influence of sea severity and mooring line pretension configuration on the operabilityof a moored vessel at a modified berthing site inside a port. A physical model was constructed to replicate thenew layout of the port of Leix
Ano: 2024
Autor(es): Abdelwahab, H.S.; Pinheiro, L.; Santos, J. A.; Fortes, C. J. E. M.; Guedes Soares, C.
Revista: Ocean Engineering
Editor: Elsevier
Volume:
291 (2024) 116243.
Keywords: Mooring pretension; Moored ship; Ship motions; Port downtime; Ship operability; Physical modelling
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Experimental study of an onshore dual chamber oscillating water column device
A wave flume is used to study a scaled model of a stepped bottom dual-chamber Oscillating Water Column (OWC) installed onshore. Compared to traditional single-chamber OWCs, the use of dual-chambers is expected to widen the range of sea states in which the OWC is more efficient, and the step, in front of the first chamber, boosts the capturing energy capacity of the device. The Power Take-Off (PTO) system is modelled as an air opening in the pneumatic chambers. Several experiments combining regular incident waves and PTO damping conditions are performed. Results of the amplitudes of the free surface elevations inside the chambers show that the device can amplify the incident wave amplitude up to 1.57 times in chamber 2. Results of the primary efficiency show that the device is highly dependent on the PTO damping characteristics and can reach around 40% for a wide range of wave periods. Results of the reflection analysis show that the reflection coefficient is also dependent on the PTO damping characteristics but remain lower than 0.6 for all the studied cases. Sloshing phenomenon (mostly in the cross-section direction) was observed for a wavelength close to the cross-section dimension, impacting negatively on the device pneumatic performance.
Ano: 2024
Número Páginas:
16p..
Autor(es): Gadelho, J.; REZANEJAD, K.; Guedes Soares, C.; Santos, J. A.; Anastas, G.; Fortes, C. J. E. M.
Revista: Ocean Engineering
Editor: Elsevier
Volume:
Volume 300 (117240).
Keywords: Reflection coefficients; Efficiency improvement; Breakwater; Experiments; Oscillating water column
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Experimental study on drag coefficient of flexible vegetation under non-breaking waves
Laboratory experiments of wave propagation over rigid and flexible vegetation fields, with the same configurations, were conducted to understand the effect of vegetation flexibility on the drag coefficient (CD). The direct method and the least squares method (LSM), based on force and flow measurements, are applied to calculate the CD in the experimental conditions. The formulations of both methods are extended to estimate the CD for flexible vegetation cases. A video analysis was performed to account for the swaying motion. Typically, wave dissipation is lower for flexible than for rigid vegetation of the same configuration, under the same flow condition. Therefore, a proportional effect in the corresponding CD results, obtained from common CD calibration to wave dissipation without considering vegetation motion, is usually observed. However, the present results show that although the wave dissipation was 34% lower for flexible relative to rigid vegetation, the respective CD values were close. CD estimations considering vegetation motion and inertia suggest that CD of flexible vegetation was up to 13% higher relative to rigid vegetation. Accounting for inertia reduced the CD for rigid vegetation up to 7%, while raised the CD for flexible vegetation up to 13%.
Ano: 2024
Número Páginas:
14p..
Autor(es): Reis, R.; Fortes, C. J. E. M.; Rodrigues, J.; HU, Z.; Suzuki , T.
Revista: Ocean Engineering
Editor: Elsevier
Volume:
Volume 296.
Keywords: Wave dissipation; Inertia; Vegetation motion; Flexible vegetation; Drag coefficient
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Exploring Wave
Aquatic vegetation in the littoral zone plays a crucial role in attenuating wave energy andprotecting coastal communities from hazardous events. This study contributes to the developmentof numerical models aimed at designing nature-based coastal defense systems. Specifically, a novelnumerical application for simulating wave
Ano: 2024
Autor(es): El Rahi, J.; Martinez-Estevez, I.; Reis, R.; Tagliafierro, B.; Dominguez, J.M.; Crespo, A.J.C.; Stratigaki, V.; Suzuki, T.; Troch, P.
Editor: MDPI
Keywords: Project chrono; DualSPHysics; SPH-FEA coupling; Fluid
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Comunicações
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Extending the H&R wave overtopping model to vertical structures
The H&R wave overtopping model, originally developed for sloping structures, is employed ina number of operational coastal flood forecasting and warning systems. This paper describesthe first step in a project to extend the model to encompass vertical structures. Use is made ofthe CLASH database for the purpose of checking whether it is appropriate to simplyextrapolate the existing formulae for the model
Ano: 2013
Número Páginas:
10p.
Autor(es): Reis, M. T.; Hedges, T.; Neves, S.; Neves, M. G.; Hu, K.; Mase, H.
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Extensão do modelo de galgamentos de Hedges & Reis a estruturas marítimas verticais
Esta comunicação analisa a aplicabilidade a estruturas marítimas verticais do modelo degalgamentos de Hedges & Reis (H&R), originalmente desenvolvido, calibrado e validado paraestruturas em talude (Hedges & Reis, 1998, 2004; Reis et al., 2008). Apresenta a comparaçãodos resultados deste modelo e de outras formulações empíricas (Pullen et al., 2007; Goda, 2008)com os dados existentes na base de dados do projeto europeu CLASH para estruturas marítimasverticais. Este estudo enquadra-se na extensão da aplicabilidade do modelo a estruturas verticais(Reis et al., 2013) e tem vindo a ser realizado por solicitação da Royal HaskoningDHV que, desde1998, tem desenvolvido sistemas de previsão e alerta de inundações nas Ilhas Britânicas,utilizando este modelo (Lane et al., 2008; Naysmith et al., 2013). Os resultados da aplicabilidadea estruturas verticais do modelo H&R existente são bastante animadores, sugerindo que a suacalibração e validação para estruturas verticais possa originar melhores estimativas dogalgamento.
Ano: 2013
Número Páginas:
18p.
Autor(es): Reis, M. T.; Neves, S.; Hedges, T.; Neves, M. G.; Hu, K.; Mase, H.
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Ferramenta para a otimização e gestão de riscos nos projectos de emissários submarinos: aplicação a um caso de estudo em Portugal
Neste estudo apresenta-se uma metodologia de avaliação de riscos para estados limitesoperativos no projecto de emissários submarinos que considera: a natureza intrínseca daestrutura, a legislação ambiental Europeia em vigor, os agentes climáticos característicos dazona costeira e a previsão do comportamento da pluma a longo-prazo.Pretende-se ainda identificar alguns padrões principais do comportamento da pluma e a suarelação com os agentes forçadores locais: vento e maré. Esses padrões são obtidos para aregião de Albufeira, onde se encontra o emissário de Vale de Faro, utilizando o método dasfunções ortogonais empíricas. A probabilidade de falha operativa ou paragem é considerada nodimensionamento probabilístico da estrutura.Com o presente estudo pretende-se estabelecer uma metodologia consistente para aoptimização e gestão de riscos no projecto de emissários submarinos com base nasRecomendações Espanholas para Estruturas Marítimas, ROM, actualmente de aplicaçãoessencialmente a portos e estruturas costeiras (Puertos del Estado, 2002). Esta metodologiapermite avaliar a segurança e operatividade de emissários submarinos e será parte integranteda ferramenta, em desenvolvimento, para a optimização e gestão de riscos nos projectos deemissários submarinos.
Ano: 2013
Número Páginas:
13p.
Autor(es): Mendonça, A. C.; Solari, S.; Losada, M. A.; Neves, M. G.; Reis, M. T.
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Força de impacto num quebra-mar misto obtidas com um modelo numérico SPH e formulações empiricas
O conhecimento dos esforços resultantes da interacção de uma onda com um quebra-marmisto torna-se essencial no dimensionamento destas estruturas. No presente trabalho, omodelo numérico SPHyCE, baseado numa metodologia de tipo SPH - Smoothed ParticleHydrodynamics, é utilizado para o cálculo das forças num quebra-mar misto. Para analisar aevolução da força de impacto, foram consideradas várias condições de profundidade no pé daestrutura e de altura de onda incidente abrangendo diferentes regimes de força.A comparação dos resultados do modelo numérico com os das formulações empíricas permitiuverificar que as forças previstas são semelhantes para os casos de regime de ondaparcialmente estacionária. No entanto, para o regime de força de impacto, existem diferençasque se devem a vários factores: i) a rebentação não ocorre sempre da forma prevista nasformulações empíricas; ii) no caso da rebentação com ar aprisionado, cuja influência no valordas forças é relevante, o modelo numérico atinge a seu limite de aplicação, pois não integra oar.
Ano: 2013
Número Páginas:
19p.
Autor(es): Didier, E.; Rodrigues, A.; Neves, M. G.; Neves, D. R.
Keywords: Formulação empíricas; Forças de impacto; Quebra-mar misto; Smoothed particle hydrodynamics; Modelação numérica
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Laboratory techniques
This work is part of the DESTAQ project (Development of advanced techniques to measure thevelocities and study the interaction between detached breakwaters and harbour structures)and aims to analyse the hydrodynamic behaviour of a detached structure as a protectionelement of a main rubble mound breakwater using laboratory tools and techniques.The hydrodynamic analysis that is presented includes image processing tools, and the use ofthe numerical model IH-2VOF. A comparison between the results obtained with bothtechniques is made.
Ano: 2013
Número Páginas:
10p.
Autor(es): Lopes, H. -; Pinto, F.; Gomes, F.V.; China, R.; Cabral, J.; Gadelho, J.; Neves, M. G.; Reis, M. T.
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LNEC experience in maritime hydraulic studies. Scale model tests and recent damage assessment techniques
N/A
Ano: 2013
Número Páginas:
23p.
Autor(es): Lemos, R.; Silva, L. G.
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MODELAÇÃO NUMÉRICA À ESCALA DO PROTÓTIPO DE UM QUEBRA-MAR DE TALUDE COM O CÓDIGO SPHyCE
O modelo numérico SPHyCE, baseado nas equações de Navier-Stokes na forma Lagrangianae numa metodologia de tipo SPH - Smoothed Particle Hydrodynamics, tem sido desenvolvidono LNEC desde 2007. Este modelo, inspirado no código SPHysics (Monaghan, 1994), integravárias opções para aplicações específicas à engenharia costeira e foi objecto de numerosasanálises de sensibilidades com vários parâmetros, estudos de convergência com a resolução evalidações com dados de ensaios experimentais realizados nas instalações do LNEC. Estesestudos foram realizados à escala reduzida dos modelos físicos testados para validação domodelo numérico. No entanto, o modelo, na sua versão actual, não foi ainda aplicado à escalado protótipo.No presente trabalho o modelo numérico SPHyCE é aplicado ao molhe Oeste do Porto deAlbufeira, no Algarve. Esta primeira aplicação tem dois objectivos:- Analisar o comportamento do modelo numérico quando aplicado a um quebra-mar à escalareal;- Aplicar uma metodologia de acoplamento entre o modelo de propagação Bouss-2D, utilizadopara propagar a onda incidente do largo até às proximidades da estrutura, e o modeloSPHyCE.Esta aplicação integra-se no projecto SPACE
Ano: 2013
Número Páginas:
21p.
Autor(es): Dias, J.; Didier, E.; Neves, D. R.; Neves, M. G.
Keywords: Galgamento; Acoplamento; Smoothed particle hydrodynamics; Modelação numérica; Efeito de escala
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Novas ferramentas para exploração de ensaios em modelo físico
Embora os procedimentos para o projeto e operação de ensaios com modelo físico reduzido deestruturas marítimas estejam já consolidados há muito tempo, continuam a existir apossibilidade e a necessidade de aperfeiçoamento de procedimentos relacionados com aexploração desta fonte de informação sobre a resposta destas estruturas à agitação marítimanelas incidente.No presente trabalho, descrevem-se metodologias recentes, implementadas no LNEC, paramelhorar os procedimentos de caracterização da envolvente do manto protetor dequebra-mares de taludes - dando-lhes um caráter mais quantitativo
Ano: 2013
Número Páginas:
16p.
Autor(es): Lemos, R.; Fortes, C. J. E. M.; Santos, J. A.; Capitão, R.; Jalles, B.
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Numerical simulation of the behaviour of a moored ship inside an open coast harbour
A set of procedures to evaluate the time series of the diffraction forces on a moored ship insidea harbor basin is presented. Nonlinear wave propagation is obtained using a Boussinesq finiteelement numerical model, BOUSS-WMH. Determination of hydrodynamic forces acting on theship is achieved using a modified version of the WAMIT model. Finally, time series of the waveforces on the ship and of the inherent moored ship motions are obtained using BAS numericalmodel. The main focuses of this work are: the coupling of these three models and themodification of the method used in WAMIT to determine diffraction forces. Some simple andpractical applications of this procedure are presented as well.
Ano: 2013
Número Páginas:
12p.
Autor(es): Pinheiro, L.; Santos, J. A.; Fortes, C. J. E. M.
Info
Numerical simulation of the behaviour of a moored ship inside an open coast harbour
Sea waves inside harbors can affect scheduled port operations. Hence it isimportant to correctly predict and characterize the wave field inside ports and to describe themovements of the ship and forces acting upon it. A classical approach is to assume that shipwaveinteraction is linear, [1]. Then it is possible to decompose it in the so-called radiationand diffraction problems. Numerical models that solve such problems have been developedand used by the offshore industry for quite a while, [2], to study the interaction of sea-waveswith floating objects. However, these models cannot be used to solve the diffraction problemof ships inside harbor basins where nearby reflecting boundaries and shallow depths createvery complex nonlinear wave fields.A new set of procedures using coupled models is proposed in this work. First, a Boussinesqtypefinite element wave propagation model is used to determine the wave field in thenumerical domain containing the harbor. Then the velocity potentials are evaluated at theship
Ano: 2013
Número Páginas:
12p.
Autor(es): Pinheiro, L.; Fortes, C. J. E. M.; Santos, J. A.; Fernandes, J. L. M.
Keywords: Panel method; Finite elements method; Ship
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Capítulos de Livros
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Multi-functional artificial reefs for coastal protection
N/A
Ano: 2009
Número Páginas:
153-210 pp.
Autor(es): Voorde, M.; Antunes do Carmo, J.; Neves, M. G.
Editor: Ch. A. Hudspeth, T. E. Reeve
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Teses de Doutoramento
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Trapped-mode propagation along irregular coasts
N/A
Ano: 1999
Número Páginas:
159 p.
Autor(es): Santos, J. A.
Editor: ******
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Probabilistic Assessment of the Safety of Coastal Structures
N/A
Ano: 1998
Número Páginas:
594 p.
Autor(es): Reis, M. T.
Editor: ******
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Unsteady Nearshore Currents on Longshore Varying Topographies
N/A
Ano: 1998
Número Páginas:
346 p.
Autor(es): Sancho, F. E.
Editor: ******
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Simulação da agitação irregular. Técnicas matemáticas
N/A
Ano: 1973
Autor(es): Carvalho, M. M.
Editor: ******
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Relatórios
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Programa definitivo das observações da natureza a realizar com vista ao ensaio do porto do Lobito.
N/A
Ano: 1952
Autor(es): Abecasis, F.
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Outros
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Risk Perception of Coastal Flooding in Praia da Vitória, Azores
The project LIFEGARACHICO (LIFE20 CCA/ES/001641) proposes the creation of an effective flexible adaptation framework for the coastal unicipalities of Macaronesia, making specific local interventions to increase their resilience against extreme coastal events resulting from climate change. Social surveys were applied in Praia da Vitória, Terceira, Azores, to understand the civilians perception of coastal flooding events.
Ano: 2024
Autor(es): Lima, L.; Fortes, C. J. E. M.; Zózimo, A. C.; Pinheiro, L.
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Social Surveys Indicating the Resilience of Urban Coastal Localities in Macaronesia to Coastal Flooding
The project LIFE-GARACHICO (LIFE20 CCA/ES/001641) proposes the creation of an effective flexible adaptation framework for the coastal municipalities of Macaronesia, making specific local interventions to increase their resilience against extreme coastal events resulting from climate change. Social surveys were applied in both localities in order to understand the civilians perception of coastal flooding events
Ano: 2024
Autor(es): Fortes, C. J. E. M.; Lima, L.; Zózimo, A. C.; Pinheiro, L.; Modino, R.; Barroso, J. G.; Cruz, C. G.; Comes, L.
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Avaliação da Estabilidade do Quebra-Mar Destacado do Porto Inglês (Ilha do Maio
Realização de ensaios em modelo físico reduzido 3D para a avaliação da estabilidade do quebra-mar destacado do Porto Inlgês, Maio, Cabo-Verde
Ano: 2023
Autor(es): Soares, R. E.; Fortes, C. J. E. M.; Lemos, R.; Costa, C.E.B.C.; Silva, L. G.; Pinheiro, L.; Neves, M. G.
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Physical modelling of wave-induced plant drag coefficient
N/A
Ano: 2019
Autor(es): Reis, R.; Suzuki , T.; LUBBERS, B.; Fortes, C. J. E. M.; Pires Silva, A.
Keywords: Flume experiments; Wave propagation; Plant flexibility; Vegetation
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Evaluation of wave overtopping consequences for risk assessment using ANP methodology
Adverse sea conditions can cause emergency situations associated to wave overtopping, which endanger the safety of people and goods, with negative impacts for society, the economy and the environment. Therefore, a methodology to assess the overtopping risk in port and coastal areas is essential for a proper planning and management of these areas.The Portuguese National Laboratory for Civil Engineering (LNEC) has been developing the HIDRALERTA system, an integrated decision-support tool for port and coastal management, which focus in preventing and supporting the management of emergency situations and the long-term planning of interventions in the study areas. It enables the user to calculate the risk for various port and coastal activities, starting with the characterization of sea-waves, wind field and tide levels at the study regions.HIDRALERTA was already tested at different places in Portugal: Costa da Caparica beach, in Almada, and port of Praia da Vitória, in the Azores. However, in both cases, the evaluation of wave overtopping / flooding consequences was carried out using a quite simple approach. In fact, such consequences were assessed only at a global and qualitative level, based on information provided by the responsible authorities.This paper aims at testing a quantitative methodology to evaluate overtopping consequences: the Analytic Network Process (ANP). This methodology was proposed to solve complex decision-making problems and its objective is to calculate the priorities among decision elements which will define their final weights on the consequences. The ANP approach can produce interdependencies between criteria and compute the respective weight of each criterion. Such a network model with dependence and feedback improves the priorities derived from judgements and makes prediction more accurate. So, the ANP allows comparison among clusters of elements. Furthermore, in this methodology we take into account the impacts of alternatives on the importance of criteria, by normalizing the comparison matrix. Thus, the given alternatives can influence the ranking of criteria.Application of the ANP methodology to the case study of Praia da Vitória port is presented and a consequences level map is obtained.
Ano: 2016
Autor(es): Lourenço, I.; Santos, J. A.; Fortes, C. J. E. M.; Reis, M. T. L. G. V.; Poseiro, P.; Craveiro, J.
Keywords: Praia da Vitória port; Analytic Network Process (ANP); Risk; Wave overtopping
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Sistema de alerta para a navegação em portos
Apresenta-se um novo sistema de alerta para navios amarrados em portos que se encontra em desenvolvimento no Laboratório Nacional de Engenharia Civil. O sistema SWAMS_ALERTA é um sistema de previsão e alerta baseado na avaliação do risco associado ao comportamento de navios amarrados em zonas portuárias.Os riscos associados a navios amarrados decorrem de movimentos excessivos, quer no plano horizontal, quer no plano vertical. Estes movimentos podem condicionar as atividades portuárias, nomeadamente cargas e descargas, mas em casos extremos podem levar à ocorrência de situações de emergência, tais como rotura de cabos, rotura de cabeços de amarração ou até colisões com o cais. As consequências deste tipo de situações envolvem sempre grandes prejuízos materiais e por vezes humanos.O sistema SWAMS_ALERTA utiliza as medições e previsões de agitação marítima para a determinação dos seus efeitos em termos de movimentos nos seis graus de liberdade e forças nas amarras e defensas quando o navio se encontra estacionado no cais. Para tal, o sistema recorre a uma série de modelos numéricos, interligados entre si. A comparação destes valores com valores máximos admissíveis pré-estabelecidos permite a avaliação, em tempo real, de situações de emergência e a emissão de alertas dirigidos às entidades portuárias.O sistema é constituído por 4 módulos:I
Ano: 2016
Autor(es): Pinheiro, L.; Lopes, P.; Fortes, C. J. E. M.; Santos, J. A.
Keywords: Navios amarrados; Riscos; Sistema de previsão e alerta
CONSTRUÇÃO DA EXPANSÃO DO PORTO DE SAL-REI 1ª FASE (ILHA DA BOAVISTA CABO VERDE) Ensaios bidimensionais em modelo reduzido Parecer Técnico
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Definição da Geometria para um Recife Artificial Multifuncional em Leirosa (Poster)
N/A
Ano: 2010
Número Páginas:
1.
Autor(es): Neves, M. G.; Antunes do Carmo, J.
Editor: Gestão Costeira: Vulnerabilidades e Riscos na Região Centro
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Probabilistic Assessment of Hazards from Overtopping of Seawalls in Urban Environments: Annual Report of pOST-dOCTORAL rESEARCH
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Ano: 2005
Autor(es): Reis, M. T. L. G. V.
Editor: ******
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Ano: 2004
Autor(es): J.A Covas
Editor: ******
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Departamento de Hidráulica e Ambiente
