Papers
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Analysis of forces on a submarine outfall by a RANS-VoF numerical wave tank
Knowledge of forces due to the action of waves on submarine outfalls composed by a pipe and stabilizing concrete weights, considering the wave propagation direction to the outfalls, is essential to their design. 3D numerical models based on RANS-VoF (Reynolds-Average-Navier-Stokes Volume-of-Fluid) are able to estimate forces on the pipe and weights. The present study aims to simulate a submarine outfall with stabilizing concrete weights at 1:15 scale which was previously tested in the 3D Shallow Water Basin at the Danish Hydraulics Institute (DHI) to analyse the influence of the direction of the incident wave and the distance from the pipe to the bottom on the outfall forces. In this study, numerical results are compared with experimental ones for waves with four different amplitudes and with wave incidence perpendicular to the outfall. The use of k-
Year: 2019
Number Pages:
50-59pp.
Author(s): Didier, E.; Neves, M. G.; Teixeira, P.
: Defect and Diffusion Forum
Editor: Trans Tech Publications Ltd, Switzerland
Volume:
Vol. 396.
Keywords: Numerical wave tank; RANS-VoF; Forces; Submarine outfalls
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Damage progression in rubble-mound breakwaters scale model tests, under a climate change storm sequence
This paper describes the two-dimensional (2D) physical model tests of a rock armor breakwater, performed at LNEC´s experimental facilities, under the framework of the HYDRALAB+ project. The aim of the present work was to evaluate damage evolution under future climate change scenarios, by using different damage evaluation techniques. The tested wave conditions simulated a storm sequence where two water levels (low water and high water) were considered, as well as an increase of the wave height. The water levels and the wave heights were chosen to simulate extreme events forecasted on climate change scenarios. Damage evaluation was based on the traditional counting method and on stereo-photogrammetric techniques. Test results are presented in terms of the damage parameter S and in terms of the percentage of removed armor units. The analysis is focused on the damage progression during the scale model tests, for the imposed storm sequence. The damage presents an oscillating behavior with two main damage areas corresponding to the active zones for each level, due to the variation of the water level between low-water and high-water. This behavior differs significantly from that found for the common storm sequences usually tested, where the water level does not change. Both measuring techniques lead to an intermediate damage of the cross-section breakwater. However, the damage parameter assessment with the stereo-photogrammetric technique allows a more versatile evaluation, since it is possible to characterize damage in representative zones of the cross-section
Year: 2019
Author(s): Fortes, C. J. E. M.; Lemos, R.; Mendonça, A. C.; Reis, M. T. L. G. V.
: Journal of Research on Engineering Structures and Materials (RESM)
Editor: MIM Research Group
Volume:
Vol. 5 Iss. 4.
Keywords: Stereo-photogrammetric techniques; Climate change; Rubble-mound breakwaters; Damage progression
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Experimental investigation on the power capture of an oscillating wave surge converter in unidirectional waves
The aim of this paper is the experimental characterization of the capture width ratio (CWR) and response amplitude operator (RAO) of a 1:10 physical model of an oscillating wave surge converter (OWSC), under unidirectional regular and irregular waves. The effects of hydraulic power take-off (PTO) system are explicitly taken in consideration. A mathematical model is proposed to describe the PTO damping as a function of the angular velocity of the flap. The harmonic decomposition of free-surface elevation, angular velocity of the flap and pressure in the PTO system demonstrates that these signals are dominated by their linear component. However, the signals also present some important higher-order frequency components. To predict the CWR of the OWSC under irregular waves the nonlinear output frequency response functions are considered as the extension of the RAO to the nonlinear case. It is shown and discussed that the PTO system, wave frequency and height have a significant influence on the CWR and RAO. The RAO curve for irregular waves does not exhibit a well-defined peak, showing a limited variation in a broadband. A weak correlation between CWR and RAO was found, i.e., the maximum CWR does not occur for the maximum value of RAO.
Year: 2019
Number Pages:
975-992pp.
Author(s): Brito, M.; Ferreira, R. L.; Teixeira, L; Neves, M. G.; R. Canelas
: Renewable Energy
Editor: Elsevier
Volume:
Volume 151.
Keywords: Power take-off: PTO damping; Response amplitude operator: RAO; Capture width ratio: CWR; Oscillating wave surge converter: OWSC; Wave energy
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Measuring wave run-up, overtopping and damage of rubble-mound breakwaters in scale model tests
A set of scale-model tests was carried out at the wave basin of the Leibniz University Hannover to extend the range of wave steepness values analysed in run-up, overtopping and armour layer stability studies, focusing on oblique extreme wave conditions and on their effects on a gentler slope breakwater
Year: 2019
Number Pages:
118-129pp.
Author(s): Santos, J. A.; Lemos, R.; Weimper, J.; Gronz, O.; Hofland, B.; Sande, J.; Pinheiro, L.; Spans, J.H.; Peña, E.; Reis, M. T. L. G. V.; Fortes, C. J. E. M.; Figuero, A.; Laiño, E.; Bornschein, A.; Kerpen
Editor: Hydralab+
Keywords: Rubble-mound breakwaters; Model tests; Overtopping; Wave run-up
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Numerical analysis of the interference between two elastically mounted cylinders in tandem subject to flows at low Reynolds numbers
Fluid-dynamic interference among cylindrical structures in arrays, frequently used in engineering, is of fundamental and practical interests since it may considerably change fluid-structure interactions and produce large fluctuating forces on structures that cause vibrations, lock-in and important motions. This paper aims to study the mutual interference between two circular cylinders in tandem arrangement, which is considered the simplest configuration of one array cylinders, elastically mounted in transversal direction and subject to a bi-dimensional uniform laminar flow at low Reynolds numbers. Both cylinders have the same diameter D and the center-to-center spacing is equal to L = 5.25D which corresponds to co-shedding regime. The academic numerical model Ifeinco, which is based on the finite element method and uses a partitioned scheme that considers two-way interaction of fluid flow and structure, has been employed to the analysis. Combinations of upstream and downstream stationary and elastically mounted cylinders are investigated for Reynolds number range from 90 to 140. Differences of flow behaviors drag and lift forces and resonance between single cylinder and cylinders in tandem arrangement were found. Mutual and respective influence of upstream cylinder motion on the downstream cylinder and vice-versa are analyzed. Results show that, in some engineering studies, the consideration of the flexibility of cylindrical structures in arrays is fundamental since it influences significantly the interference between cylinders, mainly the magnitude and direction of forces and characteristics of the resonance range, and, consequently, structural and dynamical behaviors.
Year: 2019
Number Pages:
11p.
Author(s): Teixeira, P.; Rechsteiner, P.; Didier, E.
: Journal of the Brazilian Society of Mechanical Sciences and Engineering
Editor: Springer
Volume:
Vol. 41.
Keywords: Finite element method; Vortex-induced vibration; Wake interference; Tandem arrangement; Circular cylinders
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Observação e monitorização de obras marítimas com a nova metodologia OSOM+
This paper describes a programme under the responsibility of the National Laboratory for Civil Engineering (LNEC), Portugal for the systematic observation and monitoring of maritime works, termed OSOM+, which has been applied to an extensive number of maritime structures on the Portuguese mainland coast and abroad. The OSOM+ programme comprises the following four main components for each structure: a) Periodic visual inspections by a trained technician; b) Periodic aerial inspections using a UAV/drone; c) The ANOSOM-GIS database, to store and/or query obtained information, as well as to diagnose present, evolution and risk conditions; and d) A mobile, portable, application, for real-time input and visualization of the ANOSOM-GIS database information.This recently updated methodology encompasses a number of tools whose functionalities are illustrated in this paper with an application to a case study: the Ericeira
Year: 2019
Number Pages:
22p.
Author(s): Fortes, C. J. E. M.; Capitão, R.; Henriques, M. J.; Lemos, R.; Neves, M. G.; Reis, M. T. L. G. V.; Silva, L. G.
: Revista Mundi, Engenharia, Tecnologia e Gestão
Editor: Instituto Federal do Paraná
Volume:
v.4, n.2.
Keywords: Ericeira
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A methodology to determine the optimal size of a wells turbine in an oscillating water column device by using coupled hydro-aerodynamic models
This paper describes a methodology to determine the optimal size of a Wells turbine to be used in an OWC device taking into account hydro-aerodynamic coupling, performance curves of the turbine and air pressure control by a relief valve. The proposed model, named turbine diameter optimization (TDO) model, considers the movement of the water surface inside the OWC chamber as a piston movement in response to the hydrodynamic forces from the incoming waves. The aerodynamic is based on the first law of thermodynamics applied to the air column of the chamber. The power-pressure curve of the turbine and the air pressure control by relief valve are implemented in the model to determine the turbine power output for several regular incident waves. The TDO model is initially calibrated by a numerical model based on Reynolds-Average-Navier-Stokes (RANS) equations for each wave component of an expected sea state distribution. Thereafter, the power output generated by turbines of several sizes is calculated with lower computational cost (few minutes) in comparison with RANS based models (thousands of hours) in a personal computer. This developed methodology is an important support to the process of turbine sizing for an OWC device for an expected sea state distribution.
Year: 2018
Number Pages:
9-18pp.
Author(s): Torres, F.; Teixeira, P.; Didier, E.
: Revista Renewable Energy
Editor: Elsevier
Volume:
Vol. 121.
Keywords: Air pressure control; Turbine sizing; Oscillating water column; Wave energy
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An integrated tool for modelling oscillating water column (OWC) wave energy converters (WEC) in vertical breakwaters
This paper describes the preliminary developments of an innovative integrated tool for the numerical modelling of oscillating water column (OWC) wave energy converters (WEC) integrated in vertical breakwaters. The main purpose of the tool is the numerical modelling of wave propagation from offshore to nearshore, wave-structure interaction, and the complex nonlinear hydrodynamic and aerodynamic phenomena that occur in OWC-WECs.The tool development and validation were supported by experimental data from physical model tests carried out in a wave flume at the Portuguese National Laboratory for Civil Engineering (LNEC). Prototype data were also available for the Pico OWC-WEC in the Azores, Portugal, monitored by the Portuguese Wave Energy Centre since 2005. Application of the tool for sea-wave characterization at the Azores archipelago and calculation of the corresponding wave power for a period of 10 years at various points around each island show that, in winter, there is good availability of wave energy in most quadrants of each island. In summer, the resource exploitation is only worthwhile on the north-west coasts of the islands. Physical and numerical modelling results for an OWC with a fully open chamber show good agreement between experimental data and numerical values for several incident wave conditions. The analysed results include the time series of the free-surface elevation at different locations, the time series of the mean free surface inside the water chamber, the amplification factors, the phase angles and the velocity vectors at the highest and the lowest positions of the mean free surface inside the chamber. The tool showed its potential to be useful in supporting ocean and coastal engineering projects due to its capacity to effectively reproduce the main phenomena involved in these types of studies.
Year: 2018
Number Pages:
198
Author(s): Mendonça, A. C.; Dias, J.; Didier, E.; Fortes, C. J. E. M.; Neves, M. G.; Reis, M. T. L. G. V.; Conde, J. M.; Poseiro, P.; Teixeira, P. R. F.
: Journal of Hydro-environment Research
Editor: Elsevier
Volume:
Vol. 19.
Keywords: Wave power; SWAN-URANS models; Nonlinear numerical modelling; Physical modelling; Wave-structure interaction; Oscillating water column (OWC) wave energy converter (WEC)
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Asymmetric copula
Joint statistical models for long-term wave climate are a key aspect of offshore wind engineering design. However, to find a joint model for sea-state characteristics is often difficult due to the complex nature of the wave climate and the physical constraints of seastates phenomena. The available records of wave heights and periods are often very asymmetric in their nature. This article presents a copula-based approach to obtain the joint cumulative distribution function of the significant wave heights and the up-crossing mean period. This study is based on 124-month hindcast data concerning Horns Rev 3 offshore wind farm. The extra-parametrization technique of symmetric copulas is implemented to account for the asymmetry present in the data. The analysis of the total sea, the wind-sea and primary swell components is performed separately. The results show that the extra-parametrization technique with pairwise copulas consistently provided a better goodness-of-fit when compared to symmetric copulas. Moreover, it is demonstrated that the separation of the total sea into its components does not always improve the extra-parametrized copula
Year: 2018
Number Pages:
304-334pp.
Author(s): Fazeres-Ferradosa, T.; Taveira-Pinto, F.; Vanem, E.; Reis, M. T. L. G. V.; Neves, L.
: Wind Engineering
Editor: Sage
Volume:
Vol. 42, No. 4.
Keywords: Asymmetry; Crámer
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Characterization of ship motions induced by wake waves
This paper analyses the hydrodynamic interaction between two ships, one stationary and the other navigating nearby, using physical and numerical modelling. The passing ship is a self-propelled scale model of the
Year: 2018
Number Pages:
547-555pp.
Author(s): Pedro, F.; Pinheiro, L.; Fortes, C. J. E. M.; Santos, J. A.; Hinostroza , M.
: Progress in Maritime Technology and Engineering
Editor: Taylor & Francis
Keywords: Wake waves; SWAMS; Ship motions
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Comunicação
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Estudos de agitação e ressonância no porto de Leixões
Com vista a otimizar a geometria do prolongamento do quebra-mar exterior do Porto de Leixões, bem como avaliar os impactes desse prolongamento nas condições de agitação na praia de Matosinhos, efetuou-se a caraterização da agitação marítima na zona de estudo, considerando várias soluções alternativas para o quebra-mar. A presente comunicação descreve os estudos realizados em modelo numérico para: a) o estabelecimento de regimes de agitação no exterior do porto, b) a caracterização da agitação e ressonância no interior do porto; c) a avaliação dos impactes do prolongamento do quebra-mar nas condições de agitação da praia de Matosinhos.
Year: 2018
Number Pages:
474-477pp.
Author(s): Fortes, C. J. E. M.; Neves, M. G.; Pinheiro, L.; Capitão, R.; Lopes, H.
Editor: Instituto Hidrográfico
Keywords: Modelação numérica; Ressonância; Agitação marítima; Porto de Leixões
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Evolução do dano num quebra-mar de taludes em cenários de alterações climáticas
No âmbito do projeto HYDRALAB+ (H2020-INFRAIA-2014-2015), foi realizado no LNEC um conjunto de ensaios em modelo físico bidimensional (2D) de um perfil de um quebra-mar de talude em enrocamento, construído à escala geométrica 1:30, para diferentes condições de agitação marítima e níveis de maré correspondentes a cenários de alterações climáticas. Estas experiências tinham como objetivo analisar o dano, o espraiamento e o galgamento, nesses cenários.Em paralelo, na Faculdade de Engenharia da Universidade do Porto (FEUP), e em colaboração com Deltares, NL, foram realizados testes com a mesma configuração do quebra-mar, mas utilizando um modelo físico tridimensional (3D), à escala geométrica 1:35. Os resultados obtidos permitiram analisar a evolução do dano no manto resistente do quebra-mar (talude anterior, talude posterior e cabeça), assim como o galgamento, para condições de teste com e sem sobrelevação do nível médio da água do mar, considerando ou não a reconstrução do talude do quebramar entre testes consecutivos de uma mesma série de testes. Foram também realizados testes com ondas multidirecionais.O presente trabalho incide sobre a análise da evolução do dano para as diferentes sequências de tempestade em cenários de alterações climáticas. O dano é avaliado com base no tradicional método de contagem de blocos removidos e ainda com base no parâmetro adimensional do dano, S recorrendo a técnicas estereofotogramétricas.Em termos gerais, concluiu-se que o dano era mais elevado na proximidade do nível de repouso da água e que aumentava com a altura de onda significativa. Os danos foram, em geral, menores nos testes com ondas multidirecionais. Observaram-se, ainda, diferenças significativas entre os testes com danos cumulativos e com reconstrução do quebra-mar após cada teste. Nos ensaios realizados no LNEC com aumento do nível médio do mar e alternância entre dois níveis de maré, verificou-se um ligeiro aumento do dano devido ao aumento faixa onde ocorre erosão do perfil.
Year: 2018
Number Pages:
16p.
Author(s): Lemos, R.; Fortes, C. J. E. M.; Mendonça, A. C.; Rosa-Santos, P.; Taveira-Pinto, F.; Almeida, E.; Hofland, B.
Editor: APRH
Keywords: Modelação física; Alterações climáticas; Evolução do dano
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Experimental measurments of movements and mooring forces of a ship under wave action
This paper presents a series of tests on a reduced physical model to reproduce the behavior of a moored oil tanker. The measurement techniques used and all the instrumentation are presented. Data analysis techniques are also presented. The objective of the tests is the characterization of the incident marine agitation and the response of the ship, including the movements according to 6 degrees of freedom and the forces in the mooring system.The tests were carried out in one of the tanks of the Marine Hydraulic Pavilion of the National Laboratory of Civil Engineering, using for the generation of marine agitation a batter capable of generating irregular waves.The vessel used is a scale model of the "Esso Osaka" tanker with a length of 3.43 m, a width of 0.53 m and a maximum draft of 0.23 m and is lying in terminal A of the Port of Leixões. The entire port area was built at 1:80 scale, including bathymetry and port structures. The waves are generated outside the port to the bathymetric of -20m ZHL (zero hydrographic of Leixões). Several sea states were simulated with irregular waves with periods between 10s and 16s and significant wave heights between 2m and 6m.The vessel is instrumented with an optical motion capture system according to the six degrees of freedom, composed of 4 cameras of high resolution that allows to follow the position of several targets placed in the ship and 6 load cells to measure the forces in the moorings and defenses. The measurement of free surface elevation was performed with a set of resistive probes and an ADV.
Year: 2018
Number Pages:
221-222pp.
Author(s): Pinheiro, L.; Pedro, F.; Abdelwahab, H.S.; Hinostroza , M.; Santos, J. A.; Fortes, C. J. E. M.
Editor: FEUP
Keywords: Movement and force measurement systems; Marine agitation; Ship movements; Physical model
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Galgamento em estruturas de proteção marginal face à subida de nível do mar
O sistema de proteção costeira da Cova-Gala, a sul da Figueira da Foz, inclui defesas longitudinais aderentes datadas de 1975 que têm como objetivo proteger a povoação da ação do mar. Ao longo dos anos têm-se registado eventos de galgamento destas obras que colocam em risco pessoas e bens. Face a uma possível subida do nível do mar na costa oeste portuguesa, é importante analisar a sua influência no agravamento do galgamento destas estruturas. Para tal, calculou-se o galgamento com a fórmula de Mase et al. (2013) utilizando as condições de agitação ao largo e níveis de mar obtidas de modelos de hindcast. Calculou-se ainda o caudal galgado para as mesmas condições de agitação e diferentes projeções de subida do nível do mar. A comparação de resultados permitiu concluir sobre o efeito da subida do nível do mar no galgamento para os valores considerados.
Year: 2018
Number Pages:
455-458pp.
Author(s): Pires, D.; Neves, M. G.; Oliveira, F. S. B. F.
Editor: Instituto Hidrográfico
Keywords: Subida do nível do mar; Estruturas de proteção marginal; Galgamento
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Influence of wave conditions in damages at scale model tests of rubble-mound breakwaters under sea level rising
Usually, physical model tests support the design of breakwaters considering different incident wave conditions, including extreme events. This paper describes two-dimensional physical model tests of a rock armour breakwater, performed at LNEC´s experimental facilities, under the framework of the HYDRALAB+ project. The goal of the present work is to evaluate damage evolution under wave conditions resulting from future climate change scenarios. Test results are presented in terms of the non-dimensional damage parameter (S) and of the percentage of displaced armour units (D). The data analysis is focused on the cumulative damage progression related with wave parameters as Hmax and H2%, for the imposed storm sequences. The use of the stability number (Ns), considering both H=Hs and H=H2% revealed a good agreement in order to characterize its relationship with damage evolution. On the other hand, the use of Hmax revealed a decrease of the linearity on damage evolution.
Year: 2018
Number Pages:
470-473pp..
Author(s): Lemos, R.; Neves, M. G.; Fortes, C. J. E. M.; Mendonça, A. C.; Ramos, A.; Capitão, R.; Reis, M. T. L. G. V.
Editor: Instituto Hidrográfico
Keywords: Storm sequences; Climate change; Damage evolution; Physical model
Info
Influence of wave conditions in damages at scale model tests of rubble-mound breakwaters under sea level rising
Usually, physical model tests support the design of breakwaters considering different incident wave conditions, including extreme events. This paper describes two-dimensional physical model tests of a rock armour breakwater, performed at LNEC´s experimental facilities, under the framework of the HYDRALAB+ project. The goal of the present work is to evaluate damage evolution under wave conditions resulting from future climate change scenarios. Test results are presented in terms of the non-dimensional damage parameter (S) and of the percentage of displaced armour units (D). The data analysis is focused on the cumulative damage progression related with wave parameters as Hmax and H2%, for the imposed storm sequences. The use of the stability number (Ns), considering both H=Hs and H=H2% revealed a good agreement in order to characterize its relationship with damage evolution. On the other hand, the use of Hmax revealed a decrease of the linearity on damage evolution.
Year: 2018
Number Pages:
470-473pp.
Author(s): Lemos, R.; Neves, M. G.; Fortes, C. J. E. M.; Mendonça, A. C.; Ramos, A.; Capitão, R.; Reis, M. T. L. G. V.
Editor: Instituto Hidrográfico
Keywords: Storm sequences; Climate change; Damage evolution; Physical model
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Modelação física do espraiamento e do galgamento de um quebra-mar de talude em cenários de alterações climáticas
Nesta comunicação descreve-se a análise bidimensional (2D) em modelo físico do espraiamento e galgamento de um quebra-mar de talude, em cenários de alterações climáticas, realizado no âmbito do projeto HYDRALAB+ (H2020-INFRAIA-2014-2015). Com efeito, a subida do nível médio do mar, bem como o aumento da intensidade e frequência de temporais, previsível em tais cenários, pode dar origem a fenómenos de espraiamento e galgamento das estruturas de proteção costeiras e portuárias, cada vez mais intensos e frequentes, tornando as estruturas mais vulneráveis, bem como as zonas por elas protegidas.Assim, num canal de ondas irregulares do LNEC, foi construído um perfil de um quebra-mar de enrocamento, à escala 1:30, e definido um programa de 15 ensaios, considerando valores de altura de onda significativa, período de pico e níveis de água representativos de condições de agitação incidente extremas, a que se poderão associar os referidos cenários de alterações climáticas.Para cada ensaio, efetuaram-se medições da elevação da superfície livre, do espraiamento e do caudal médio galgado. Os valores experimentais de espraiamento e de galgamento foram comparados com os previstos pelas formulações empíricas do EurOtop, para um dos cenários de alterações climáticas testado.
Year: 2018
Number Pages:
11p.
Author(s): Mendonça, A. C.; Lemos, R.; Fortes, C. J. E. M.; Capitão, R.; Neves, M. G.; Reis, M. T. L. G. V.
Editor: APRH
Keywords: Galgamento; Espraiamento; Fórmulas empíricas; Modelação física; Alterações climáticas
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Observing and monitoring maritime works through the use of the new OSOM+ methodology
This paper describes a programme under the responsibility of LNEC for the systematic observation and monitoring of maritime works, termed OSOM+, that has successfully been applied to an extensive number of maritime structures on the Portuguese mainland coast and abroad.The OSOM+ programme comprises the following four main components for each structure: Periodic visual inspections by a trained technician; Periodic aerial inspections with a UAV/drone; The ANOSOM-GIS database, to store and/or query obtained information, as well as to diagnose present, evolution and risk conditions; A mobile, portable, application, for real-time input and visualization of the database information.This recently updated methodology encompasses a number of tools and functionalities that are illustrated in this paper with applications to a real case scenario, the Ericeira
Year: 2018
Number Pages:
2035-2050pp.
Author(s): Fortes, C. J. E. M.; Capitão, R.; Henriques, M. J.; Lemos, R.; Neves, M. G.; Reis, M. T. L. G. V.; Silva, L. G.
Editor: FURG
Keywords: Ericeira
Info
Physical modelling of motions and forces on a moored ship at the Leixões port
This paper describes the physical model, experimental setup and tests performed at the Portuguese Civil Engineering Laboratory (LNEC), to study the motions and forces of a moored ship at the Leixões port, for different sea states in irregular waves. The tests were carried out at one of the wave tanks of LNEC, where the Leixões port layout was implemented at scale 1:80 with the detailed model similar to the prototype bathymetry and surrounding structures. The moored ship is a 3.43 m long scale model of the well-known
Year: 2018
Number Pages:
2501-2517pp.
Author(s): Santos, J. A.; Pinheiro, L.; Abdelwahab, H.S.; Pedro, F.; Fortes, C. J. E. M.; Capitão, R.; Hinostroza , M.; Guedes Soares, C.
Editor: FURG
Keywords: Physical modelling; Irregular waves; Fenders; Mooring loads; Ship motions
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Reliability of scour protections with copula-based models
Scour protections are commonly designed according to semi-empiric methodologies, which are based on a deterministic approach. This often results in overestimated dimensions of the protection, namely, regarding the required minimum stone size for offshore engineering. Therefore, excessive costs of the protection are expected, when the deterministic design methodology is used. Moreover, these methodologies do not provide a measure of safety associated to the design of the scour protection. In this paper, one uses copulas theory to model the correlated long-term behaviour of the significant wave height and peak period. The statistical models are then used to address the probability of failure of a case study scour protection. The results show that the copula models influence the safety assessment of the scour protection. The research also includes a brief analysis of physical model tests, which were successfully used to define dynamically and statically stable scour protections for the case study analysed.
Year: 2018
Number Pages:
9p.
Author(s): Fazeres-Ferradosa, T.; Taveira-Pinto, F.; Reis, M. T. L. G. V.; Neves, L.
Editor: IHCantabria
Keywords: Physical modelling; Probability of failure; Scour protection; Copula
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Capítulo de Livro
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Multi-functional artificial reefs for coastal protection
N/A
Year: 2009
Number Pages:
153-210 pp.
Author(s): Voorde, M.; Antunes do Carmo, J.; Neves, M. G.
Editor: Ch. A. Hudspeth, T. E. Reeve
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Tese de Doutoramento
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Trapped-mode propagation along irregular coasts
N/A
Year: 1999
Number Pages:
159 p.
Author(s): Santos, J. A.
Editor: ******
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Probabilistic Assessment of the Safety of Coastal Structures
N/A
Year: 1998
Number Pages:
594 p.
Author(s): Reis, M. T.
Editor: ******
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Unsteady Nearshore Currents on Longshore Varying Topographies
N/A
Year: 1998
Number Pages:
346 p.
Author(s): Sancho, F. E.
Editor: ******
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Simulação da agitação irregular. Técnicas matemáticas
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Year: 1973
Author(s): Carvalho, M. M.
Editor: ******
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Relatório Científico
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An integrated harbour navigation control system. NATO Po-Navigation. Adenda ao "Project Plan" proposto ao "Programa Ciência para a Estabilidade. Fase III" da OTAN
N/A
Year: 1994
Author(s): Covas, J. A.
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Cais da Calheta, Ilha de S. Jorge - Açores. Memorando
N/A
Year: 1994
Author(s): Silva, L. G.
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Ensaios em modelo reduzido de uma protecção marítima aderente.
N/A
Year: 1994
Author(s): Silva, L. G.
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Ensaios tridimensionais de estabilidade e galgamentos do molhe de protecção do porto de recreio náutico do porto de Sines.
N/A
Year: 1994
Author(s): Silva, L. G.
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Estudo da localização de um terminal de importação de gás natural liquefeito. Análise das condições do porto de Sines. Estudos de agitação marítima.
N/A
Year: 1994
Author(s): Capitão, R.
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Estudo da localização de um terminal de importação de gás natural liquefeito. Selecção de locais viáveis. Estudos de agitação marítima.
N/A
Year: 1994
Author(s): Capitão, R.
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Ligação da lagoa de Óbidos ao mar - Estudos de agitação marítima.
N/A
Year: 1994
Author(s): Carvalho, M. M.; Capitão, R.; Fortes, C. J. E. M.; Covas, J. A.
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Year: 1994
Author(s): Covas, J. A.; Fortes, C. J. E. M.
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Year: 1994
Author(s): Covas, J. A.; Fortes, C. J. E. M.; Capitão, R.
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Year: 1994
Author(s): Covas, J. A.
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Year: 1998
Number Pages:
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Editor: ******
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Year: 1998
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Year: 1998
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Year: 1998
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Year: 1998
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