Publicações

The Port of Sines is located on the west coast of Portugal, sheltered by two breakwaters: thewest and the east breakwaters (Figure 1). Originally, the west breakwater was 2 km long indepths up to 50 m, protected by two armour layers of 400 kN dolosse on a 1:1.5 slope(Mettam, 1976). In February 1978, immediately after breakwater construction, a storm, with asignificant wave height of 8 m, damaged the breakwater armour layer in four different areas.One year later, a more severe storm caused failure of almost the entire armour layer andsuperstructure, leading to urgent repair works during the 1980s. The last rehabilitation workswere concluded in 1992.

O conhecimento da agitação marítima é fundamental para o planeamento de intervenções e estudos costeiros, para simular os possíveis impactos ambientais de obras de engenharia e para a definição de procedimentos em situações de emergência. Os modelos numéricos de propagação de ondas, devido à sua rapidez, flexibilidade e gama de aplicação, contribuem de forma importante para os estudos costeiros. Apesar destas qualidades permitirem a simulação de diversos cenários de forma simplificada, os modelos exigem a utilização de grandes quantidades de dados e originam também grandes quantidades de resultados para cada caso em estudo.Os sistemas de informação geográfica permitem a organização e interpretação de grandes quantidades de informação, mostrando de forma rápida os padrões e tendências principais em qualquer processo de tomada de decisão.Neste âmbito tem vindo a ser desenvolvido o sistema GUIOMAR: Geo(Graphical) User Interface for cOastal and MARine modeling, um sistema integrado para a modelação da agitação marítima, aplicado à zona costeira portuguesa e que inclui todas as funcionalidades de um SIG.A versão actual do sistema foi desenvolvida em linguagem VBA (Visual Basic for Applications) para o ArcGIS9.0TM. O sistema GUIOMAR tem 3 componentes principais: (i) um software comercial de SIG; (ii) uma interface com o utilizador que é responsável pela comunicação entre o utilizador e o sistema; (iii) um conjunto de modelos de propagação de ondas, com diferentes domínios de aplicação: REF/DIF 1(Dalrymple e Kirby, 1991), REF/DIF S(Kirby e Ozkan, 1994), FUNWAVE 1D e 2D (Kirby et al., 1998), DREAMS (Fortes, 2002) e SWAN (Booij et al., 1999); Inclui também um programa de construção de malhas não estruturadas para os modelos numéricos, GMALHA (Pinheiro et al., 2006).O trabalho apresenta numa aplicação do sistema GUIOMAR ao Porto de Sines na qual foram testados os desenvolvimentos mais recentes do sistema, como é o caso da acoplagem dos modelos de propagação de ondas DREAMS e SWAN através da interface do GUIOMAR. Para tal, foi efectuada uma caracterização intensiva do Porto de Sines para o cálculo dos coeficientes de reflexão a aplicar no modelo DREAMS. O resultado final deste trabalho foi a caracterização do regime de agitação marítima dentro e fora do porto de Sines através da utilização dos procedimentos implementados no sistema GUIOMAR.

GUIOMAR is an integrated system for coastal engineering modeling, developed with a commercial software of Geographical Information Systems (GIS). This system allows the utilization of both wave propagation models and of all the functionalities that are inherent to the GIS software, and it is being designed to help in the decision making process in coastal areas. GUIOMAR system is composed of three main components: a GIS commercial software, a set of modules/models of wave propagation and other pre and post processing algorithms programmed in FORTRANTM, and a Graphical User Interface (GUI) developed in VBA for ArcGISTM, which is responsible for the communication between the user and the system. At the moment, are available six wave propagation models and a program that automatically generates unstructured grids for the numerical models. In this paper, GUIOMAR structure and a general overview of its interface are presented. In order to achieve important information about the system operability, a test was made for an important Portuguese harbor. Sines harbor, at the southeast of Europe, 37º 57

This paper describes the implementation of a new boundary conditions in the BOUSSIIW model (BOUSSinesq model with Internal Irregular Wave generation). BOUSSIIW is a finite element numerical model for wave propagation in near shore regions that is able to describe the wave field outside and inside harbours and sheltered zones. It is based upon the extended Boussinesq equation derived by Nwogu. These equations describe the nonlinear evolution of waves over a sloping impermeable bottom and are able to reproduce some of the most important physical effects associated with the nonlinear wave transformation in near shore regions. Their range of validity extends from shallow up to intermediate water depths. Monochromatic and irregular waves can be generated by the model using the source function method. The two boundary conditions available were full reflection or full absorption. A new partial reflection boundary condition is implemented. The model is validated with a simple test case. Reflection coefficients obtained with BOUSSIIW were compared to widely used empirical formula, enabling the assessment of the new condition

In the framework of a research project entitled

N/A

This paper presents the results of the study performed for estimating the run-up and flood levelsin a stretch of Vale do Lobo beach, located at Loulé Municipality, in the Algarve region.The study started by defining the offshore wave conditions in the area, based upon data collectedduring 1991 by the Portuguese Hydrographic Institute with a directional wave-buoy located atFaro. These conditions were then transferred to the vicinity of Vale do Lobo beach by using theGUIOMAR system, namely its SWAN module. GUIOMAR is an integrated system for modellingwave propagation in coastal engineering studies. It is currently being developed to providesupport for a sustainable planning and management of the costal area.Two empirical formulations were applied for estimating the run-up at Vale do Lobo beach during1991: one based on field data and the other based on physical model tests. Two water levelswere considered and a sensitivity analysis was performed to evaluate the differences betweenthe two formulations and the impact of some of the parameters on the end results. The floodlevels were also estimated.

This paper presents an experimental and numerical study of 2-D wave diffraction by a fixed horizontal-axis submergedcircular cylinder. The objective of the paper is to report and validate results from the fully nonlinear 2-D boundary-elementmethod code CANAL; to assess the capability of the physical wave flume and the measurement methodology to study thistype of problem; and to contribute to the understanding of the wave diffraction by a circular cylinder. Two test cases arepresented, both in deep-water conditions. The cylinder axis submergence is 1^5r (r is the cylinder radius) for the first case,and 3r for the second, the latter corresponding to the experimental study presented in the paper. A discretization convergenceevaluation is also presented for the second case. The good agreement between the numerical and the experimental resultsproves that this numerical model is able to accurately simulate this type of problems. No reflection was noticed on the incidentwave side of the cylinder. It was found that nonlinear resonant interactions occur between the fundamental frequency andthe harmonics on the transmitted wave side of the cylinder. Free waves were observed on this part of the wave flume.

This paper describes the application of the Boussinesq model (FUNWAVE 2D) to study the wave propagation inthe vicinity of an artificial reef, to be implemented at S. Pedro do Estoril, Cascais, Portugal. First, the model wascalibrated using measurements obtained in the 3D experiments performed at the wave tank of LNEC (scale1:30). Then, an evaluation of the model performance is presented. For that, a comparison between numerical andphysical model results in terms of the free surface elevation and wave heights is done for some incident waveconditions. It is shown that the numerical model predicts wave heights that are comparable to measurements ifthe wave breaking sub-model is properly tuned for dissipation over the artificial reef.Finally, the model was used to evaluate the reef performance in terms of the hydrodynamics around the reef, thewave breaking area and the surfability parameters.The numerical results confirm that the reef alters significantly the wave heights and wave directions in the zone,due refraction and diffraction effects. Best surf conditions (plunging waves with adequate values of the peelangle) occur with the reef for most of the tested conditions.

Portugal is one of many countries in the world to suffer from coastal erosion. Conventional ways of protecting acoastline appear to entail some disadvantages. An innovative and interesting way of protecting a local coastalzone by means of multi-functional artificial reefs avoids some of them. A multi-functional artificial reef is asubmerged breakwater which protects the local coastline and may also enhance the surfing possibilities and theenvironmental value of the local area. The structure has several positive side-effects: first, it provides anunimpaired visual amenity; second, it offers tourist and economic benefits by improving the surfing. A physicaland numerical study has been undertaken to investigate the influence of the length and submergence of the reef.Preliminary conclusions on the length of the reef suggest that it should be 0.5 times the wave length at the startof the reef, and regarding the submergence they indicate that a value smaller than the offshore wave height isnecessary to get a surfable wave for a reef slope of 1:10.

Coastal vegetation can contribute to protect the coasts from sea wave action, as controlling local biology and morphodynamics. A common way to estimate the wave energy dissipation over vegetation is to use the Mendez and Losada (2004) analytical formulation in combination with the calibrated bulk drag coefficient parameter (CD). However, an excessive range of CD values is found in the literature related to same Reynolds (Re) or Keulegan-Carpenter (KC) numbers. This may be due to a lack of universality of the empirical equations proposed and/or limitations of the analytical model. The numerical model SWASH (Zijlema et al., 2011) characterises wave dissipation over vegetation fields (Suzuki et al., 2019, 2022; Reis et al., 2020) considering the influence of the drag, inertia, and porous effects on cylindrical structures. Potentially, SWASH offers enhanced capacities to describe the physical processes involved and to calibrate associated CD values. Wave dissipation over vegetation data was collected by performing laboratory flume experiments, enabling an ideal control of the study conditions. The analytical formulation and the SWASH numerical model are applied to estimate the wave dissipation obtained in the experiments, through the calibration of the CD.The objective of this study is to investigate: i) how the analytical and SWASH models can represent the experimental wave dissipation, and ii) the calibrated CD values obtained from each modelling approach.

Downtime of port terminals results in large economic losses and has a major impact on the overall competitiveness of ports. Early Warning Systems (EWS) are an effective tool to reduce ports

Aquatic vegetation in the littoral zone, particularly seagrass, is gaining increasing recognition for its net positive impact on the hosting environment. This recognition is rooted in its capacity to absorb wave energy, regulate water flow, and manage nutrient levels, sedimentation and accretion. Thus, there is a growing interest in integrating seagrass as a key component of a comprehensive climate-conscious strategy (Ondiviela et al., 2014). An effective approach to quantify the positive potential of seagrasses in altering coastal wave dynamics is by using numerical models. These numerical models operate at various spatio- temporal scales, ranging from large domains and multiple years to just a few regular waves in high resolution CFD numerical simulations. Zeller et al. (2014) classified these models, operating at different scales into three categories, each addressing the wave-vegetation interaction at a distinct scale: (1) blade scale, (2) meadow scale, and (3) ecosystem scale. The aim of the present study is to investigate the interaction between waves and vegetation at the blade scale. The primary objectives are two: first, to introduce a direct numerical technique that involves a two-way coupling between a fluid solver and a structural solver, and second, to present novel experimental data for a single flexible cylinder (Reis, 2022) serving as validation for the present (and future) numerical model(s).

The present work describes the developments done so far to the Praia da Vitoria coastal region under the LIFEGARACHICO project, namely the implementation of module on HIDRALERTA early warning system foremergency response to coastal waver topping and flooding at Praia da Vitória bay.

The present work describes the developments done so far to the Praia da Vitoria coastal region under the LIFE-GARACHICO project, namely the implementation of module on HIDRALERTA early warning system for emergency response to coastal waver topping and flooding at Praia da Vitória bay.

O acesso marítimo ao Porto de Aveiro apresenta problemas de navegabilidade que condicionam a entrada de navios de grande dimensão, em particular em algumas situações de maré e agitação marítima. Este estudo apresenta e avalia uma configuração alternativa para a embocadura da Ria de Aveiro que visa mitigar estes problemas.

O acesso marítimo ao Porto de Aveiro apresenta problemas de navegabilidade que condicionam a entrada de navios de grande dimensão, em particular em algumas situações de maré e agitação marítima. Este estudo apresenta e avalia uma configuração alternativa para a embocadura da Ria de Aveiro que visa mitigar estes problemas.

Docking large vessels is a delicate operation as the kinetic energy associated with the large mass of the vessel can result in high impact forces that can damage the vessel, fenders or even the quay. Berthing loads are usually quantified using design formulae based on kinetic energy and a single point of impact. Some correction factors are then used to consider the hydrodynamic mass, the ship

Docking large vessels is a delicate operation as the kinetic energy associated with the large mass of the vessel can result in high impact forces that can damage the vessel, fenders or even the quay. Berthing loads are usually quantified using design formulae based on kinetic energy and a single point of impact. Some correction factors are then used to consider the hydrodynamic mass, the ship

This communication describes the methodologies applied in the conception, implementation, andanalysis of a set of surveys on the risk perception of coastal flooding, carried out in the community ofPraia da Vitória (Azores, Terceira Island, Portugal).This work is part of the project LIFE-GARAC HICO* (LIFE20 CCA/ES/001641), whose objectiveis to create a Flexible Adaptation Strategic Framework for the coastal municipalities of Macaronesia, toincrease the resilience of these areas in face of current and future (considering climate change impacts)coastal extreme events. The project follows a co-participatory approach, to promote awareness amongthe population and increase reliability in coastal risk management. Indeed, involving all the existentstakeholders is the first step in promoting a democratic risk management, which in the end, leads to aresilience increase, in the face of global warming conditions.

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

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.

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

Realização de ensaios em modelo físico reduzido 3D para a avaliação da estabilidade do quebra-mar destacado do Porto Inlgês, Maio, Cabo-Verde

N/A

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.

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

N/A

N/A

N/A