Josep Ramon Medina

Universitat Politècnica de València | UPV · School of Civil Engineering

Breakwaters protecting harbors and coastal areas are key to the economic and social development of many countries, but they are also infrastructures which may result in relevant environmental and social impacts. The construction of new breakwaters in developing countries, together with the dismantling, rehabilitation or repair of old breakwaters in...

Mound breakwaters are widely used to protect harbors from wave attack. Wave overtopping is a key parameter on the breakwater design, since it affects the hydraulic stability, the port operativity and also generates risks to the facilities, vehicles and pedestrians. The estimation of the mean wave overtopping rate, q[m3/s/m], has been extensively an...

In the last two decades, Eco-engineering has emerged to mitigate and compensate the environmental impacts of man-made structures while integrates benefits to society, being concrete the most widely alternative material used to natural rocks for construction of artificial coastal structures. Over the past three decades, an extensive literature has d...

In order to evaluate the hydraulic performance of breakwaters, mechanical profilers were first used in wave flumes. Vertical bars and rolling wheels have been used to track the breakwater shape. Once surveyed, useful hydraulic parameters were able to be measured (e.g., envelope shape and eroded area). Nevertheless, the methodologies based on mechan...

This study develops a calibration method for the porous media to properly model the interaction between waves and coastal structures using VARANS models. The proposed method estimates the porosity, np, and the optimum values of the Forchheimer coefficients, and . Physical tests were conducted in a 2D wave flume for a homogeneous mound breakwater. N...

This study develops a calibration method for the porous media to properly model the interaction between waves and coastal structures using VARANS models. The proposed method estimates the porosity, np, and the optimum values of the Forchheimer coefficients, α and β, that best represent the wave-structure interaction for a complete set of laboratory...

Placement grid design is a key element for the correct construction of breakwaters. This study presents a numerical model to simulate a realistic placement procedure of armor units during the construction of mound breakwaters. This numerical model is based on the Bullet Physics Engine (BPE) method applied to Cubipod Homogeneous Low-Crested Structur...

Armor erosion due to wave attack has been studied intensively since it is considered the main failure mode of mound breakwaters. Cube-armored mound breakwaters in depth-limited breaking wave conditions are common in practice but have received limited attention in the literature. In this study, 2D physical tests were performed on non-overtopped doub...

Sustainable Development has gained prominence in the last decades; Agenda 2030 for Sustainable Development was approved in 2015 to provide a roadmap to achieve Sustainable Development including 17 Sustainable Development Goals (SDGs). Consequently, major associations related to engineering education are promoting the inclusion of sustainability int...

Homogeneous low-crested structures (HLCSs) on hard seabed are designed to protect beaches and regenerate coral reefs. The height of a HLCS depends on the placement grid which determines the crest freeboard, wave transmission and concrete consumption. In real seafloor conditions, it is not easy to define feasible placement grids for HLCSs on uneven...

Armor damage due to wave attack is the principal failure mode to be considered when designing conventional mound breakwaters. Armor layers of mound breakwaters are typically designed using formulas in the literature for non-overtopped mound breakwaters in non-breaking wave conditions, although overtopped mound breakwaters in the depth-induced break...

In many countries, the health of the marine ecosystems and the sun-sand-sea tourism depend on the coral reefs, which have been retreating around the world during the last decades. Homogeneous Low-Crested Structures (HLCS), made of large rocks or pre-cast concrete units, can be placed to mimic the functions of beach protection and eventually serve a...

ARJ-R caissons are based on the "long-circuit" concept (Medina et al, 2016) that allows the extension of the destructive wave interference mechanism to mitigate low frequency oscillations without enlarging the width of the caisson. The performance of the ARJ-R caissons is referred to its reflection coefficient (Cr) which was obtained through large-...

This study focuses on container vessel fuel consumption considering the wind conditions along the ship path in the liner route. Simple analytical and semi-empirical formulas are provided to estimate the total resistance force and the bunker consumption rate of fully loaded containerships between 5000 and 15000 TEU considering the effect of wind and...

Sea level rise due to climate change, as well as social pressure to decrease the visual impact of coastal structures, have led to reduced crest freeboards, and this increases the overtopping hazard. In previous studies, pedestrian safety during overtopping events was assessed considering the overtopping layer thickness (OLT) and the overtopping flo...

The authors would like to make the following corrections about the published paper [...]

The influence of parapets on crown walls of mound breakwaters on wave forces has not been extensively analyzed in the literature. In this study, numerical experiments were carried out using the open-source platform OpenFOAM® to evaluate the influence of nine crown wall geometries with and without parapets. The OpenFOAM® model was validated with lab...

Mound breakwaters are usually designed to limit the mean wave overtopping rate (q) or the maximum individual wave overtopping volume (Vmax). However, rarely do studies focus on wave overtopping volumes on breakwaters in depth-limited breaking wave conditions. This study analyzes 2D physical tests on mound breakwaters with relevant overtopping rates...

The crest elevation of mound breakwaters is usually designed considering a tolerable mean wave overtopping discharge. However, pedestrian safety, characterized by the overtopping layer thickness (OLT) and the overtopping flow velocity (OFV), is becoming more relevant due to the reduction of the crest freeboards of coastal structures. Studies in the...

Background literature on the influence of parapets on the overtopping of mound breakwaters is limited. In this study, numerical tests were conducted using computational fluid dynamics (CFD) to analyze the influence of nine crown wall geometries (seven with parapets). The CFD model was implemented in OpenFOAM ® and successfully validated with labora...

Mound breakwater design is evolving owing to rising sea levels caused by climate change and social concern regarding the visual impact of coastal structures. The crest freeboard of coastal structures tends to decrease while overtopping hazard increases over time. Pedestrian safety when facing overtopping events on coastal structures has been assess...

Tourism activities associated with sandy beaches are essential to the economy of many countries around the world. The stability of many tropical beaches depends on the health of adjacent coral reefs. The retreat and progressive degradation of coral reefs reflect the poor health of the world´s marine ecosystems and threaten the economy and marine bi...

Conventional mound breakwaters are usually designed to withstand low mean wave overtopping discharges and a low proportion of overtopping waves (Pow). Existing formulas to estimate Pow and maximum individual wave overtopping volume are usually based on tests with high Pow; this study is focused on mound breakwaters subjected to Pow < 0.2. The perfo...

Resumen El aumento global de la temperatura del agua marina, la acidificación de los océanos y otros impactos negativos de las actividades humanas están dañando los arrecifes de coral en el mundo y reduciendo los servicios ecosistémicos que proporcionan. El retroceso y degradación progresiva de los arrecifes de coral observado en el Caribe, Austral...

The armor layer of a mound breakwaters is usually designed with a formula derived from physical tests in non-breaking wave conditions; however, most rubble mound breakwaters are placed in the wave breaking zone where the highest waves break before reaching the structure. The hydraulic stability formulas developed for rock-armored breakwaters in non...

Breakwaters provide convenient shelter for short-period waves, thus limiting the amount of energy entering the harbor. This wave energy in the port basins may be amplified, due to the wave reflection, disturbing port operations. Anti-reflective Jarlan-type (ARJ) structures (see Jarlan, 1961) have been proposed in the literature, along with other st...

Armor stability formulas for mound breakwaters are commonly based on 2D small-scale physical tests conducted in non-overtopping and non-breaking conditions. However, most of the breakwaters built around the world are located in breaking or partially-breaking wave conditions, where they must withstand design storms having some percentage of large wa...

Mound breakwaters with significant overtopping rates in depth-limited conditions are common in practice due to social concern about the visual impact of coastal structures and sea level rise due to climatic change. For overtopped mound breakwaters, the highest waves pass over the crest producing armor damage, not only to the front slope, but also t...

Low Crested Structures (LCS) have had promising results in attenuating erosion problems in touristic coastal zones where the economic activity shows strong dependency on natural resources. A homogeneous Cubipod LCS is presented here as a solution to mitigate coastal erosion, considering landscape aesthetics, coral reef biodiversity and climate chan...

In recent years, mound breakwater design has had to consider social concerns about the visual impact of coastal structures as well as the rise in sea levels due to climate change. Additionally, mound breakwater design must consider pedestrian safety when facing overtopping loads and the subsequent hazards. The overtopping hazard on dikes has been s...

In this study, seven input variables are used to estimate wave forces on the crown wall, and explanatory variables are ranked using neural network techniques. 274 small-scale 2D tests, including both wave overtopping and pressure on crown-wall measurements, were used to calibrate the wave force predictors. Wave overtopping (log Q) was the most rele...

Armor layers of mound breakwaters are usually designed with empirical formulas based on small-scale tests in non-breaking wave conditions. However, most rubble mound breakwaters are constructed in the depth-induced breaking zone, where they must withstand design storms having some percentage of large waves breaking before reaching the structure; in...

This paper describes the design process and hydraulic stability tests corresponding to the western breakwater in the outer port at Punta Langosteira (A Coruña, Spain). This breakwater is the second phase of the 1.35 km-long secondary breakwater; the first phase was the single-layer Cubipod armored southern breakwater. The western breakwater is prot...

This paper describes the design process, hydraulic stability tests and construction of the Cubipod® armored Western breakwater at Punta Langosteira (Outer Port of A Coruña, Spain), located on the Atlantic coast of Spain. The environmental, geotechnical, economic and logistic conditions favored randomly-placed Cubipods for single-layer armoring of...

It is common to construct a rock toe berm of three to four rocks wide when concrete armor units are placed in the armor layer. This toe berm is a relevant element, especially in very shallow waters combined with steep sea bottoms, where waves directly attack the toe berm and the lowest part of the armor. Several formulas are available to estimate t...

The roughness factor (γf) is a key variable to estimate wave overtopping discharge on mound breakwaters. In this study, the γf is re-calibrated using a dataset extracted from the CLASH database. Compared to previous roughness factors calibrated using less restrictive data, overtopping estimators with a few explanatory variables showed variations...

La determinación de la cota de coronación de los diques en talud es un aspecto fundamental en su diseño ya que tiene una repercusión directa sobre el coste de la estructura y su impacto visual. Habitualmente, para su determinación se fija una tasa promedio de rebase en fase de diseño que puede diferir más de dos órdenes de magnitud con el rebase in...

Cubipod® Manual 2016 provides basic criteria for the preliminary design of mound breakwaters protected with single- or double-layer Cubipod® armors. Economic, logistic and environmental factors are analyzed to guide the designers in the preliminary design phase of a breakwater. The economic cost of a large mound breakwater usually depends on the ge...

En este artículo se describen los aspectos innovadores del diseño y proceso de construcción del dique Oeste del puerto exterior de A Coruña en Punta Langosteira. El contradique del puerto está formado por el dique sur (fase 1.a) y el dique Oeste (fase 2.a), actualmente en construcción, y tiene la función de completar el abrigo proporcionado por el...

When mound breakwaters are placed on steep sea bottoms in combination with very shallow waters, the design of the toe berm becomes a relevant issue. Toe berms built close to the water surface on a steep sea bottom must withstand such high wave loads that their design may not be feasible with available quarrystones. In this study, a new design metho...

Based on the Crest Level Assessment of Coastal Structures (CLASH) Neural Network Overtopping prediction method, a new 16-parameter overtopping estimator (Q6) was developed for conventional mound breakwaters with crown walls, both with and without toe berms. Q6 was built up using the overtopping estimations given by the CLASH Neural Network and chec...

El Manual del Cubípodo® 2015 proporciona unos criterios básicos para el diseño y construcción de diques en talud protegidos con mantos monocapa y bicapa de Cubípodos. Se describen los factores principales a tener en cuenta en la fase de pre-diseño de diques rompeolas en general y de mantos de Cubípodos en particular. La selección de la geometría de...

The toe berm is a relevant design element when rubble mound breakwaters are built on steep sea bottoms in breaking conditions. Different design formulas can be found in the literature to predict the damage caused to submerged toe berms placed on gentle bottom slopes. However, these formulas are not valid for very shallow waters in combination with...

The stability of cube-armored breakwaters, with random and uniform placement, was analyzed using artificial neural networks (NN). Small-scale 2D physical tests were conducted in the wind and wave test facility of the Laboratory of Ports and Coasts at the Universitat Politècnica de València (UPV). The tested models corresponded to double-layer cube-...

Overtopping estimation on mound breakwaters depends on climatic and geometrical variables. The roughness factor (γf) is commonly used in overtopping estimators to take into account the armor unit shape, placement, number of layers and permeability. Usually, the γf given in the literature is associated with the armor unit type and number of layers....

Los elementos del manto principal de un dique en talud pueden colocarse con una orientación prefijada (colocación regular) o sin ella (colocación aleatoria). Los elementos masivos de hormigón, como los bloques cúbicos o paralelepipédicos, suelen disponerse con colocación aleatoria. Sin embargo, no es habitual cuantificar esa aleatoriedad, ni a esca...

Del estudio de la literatura científica se deduce que la porosidad del manto principal de muchos tipos de piezas (escollera, cubos, Tetrápodos, Dolos, etc.) afecta significativamente su estabilidad hidráulica. Sin embargo, existen muy pocas formulaciones de estabilidad hidráulica del manto donde la porosidad del manto o la densidad de colocación de...

La pendiente de fondo existente delante de un dique en talud influye significativamente sobre las alturas de ola que inciden sobre la estructura, uno de los factores fundamentales en el cálculo del caudal de rebase. Sin embargo, entre las variables explicativas de las formulaciones empíricas existentes no se encuentra la variable pendiente de fondo...

The roughness factor (γf) is a parameter used in overtopping estimators to account for the effects of armor unit geometry, the number of layers in the armor and other structural characteristics. Different values of γf for the same armors are given in the literature; however, in this study, the value of γf was calibrated for each overtopping estimat...

Armour placement and packing density directly affect construction costs and hydraulic performance of mound breakwaters. In this paper, the literature concerning the influence of armour porosity on the hydraulic stability of single- and double-layer armours is discussed. Qualitative and quantitative estimations for the influence of armour porosity a...

Most mound breakwaters are constructed in the surf zone, where they are attacked by waves breaking on the sea bottom. When they are built on steep foreshore slopes, most are placed in very shallow water; in these conditions the toe berm stability is a critical issue. Several empirical formulas have been published to predict damage to toe protection...

This paper describes the evolution of design techniques applied to mound breakwaters as well as some key tools, equipment and construction techniques. The influence of the theoretical and laboratory research is analyzed in detail, from the pioneering research by Iribarren eighty years ago to the construction of single-layer armored breakwaters in r...

Although little attention is usually given to the armor porosity and armor randomness of randomly placed concrete armor units in mound breakwaters, significant model effects may occur if armor porosity and randomness are different for prototype and small-scale models. Armor randomness and porosity are easier to control in small-scale models because...

Armor porosity significantly affects construction costs and hydraulic stability of mound breakwaters; however, most hydraulic stability formulas do not include armor porosity or packing density as an explicative variable. 2D hydraulic stability tests of conventional randomly-placed double-layer cube armors with different armor porosities are analyz...

This paper describes the design process, hydraulic stability tests and construction of two single-layer Cubipod armored breakwaters in the Port of Punta Langosteira (A Coruña, Spain), located on the Atlantic coast of Spain, the first single-layer armors of randomly placed massive concrete armor units. The environmental, geotechnical, economic and l...

This paper describes the heterogeneous packing (HEP) failure mode of breakwater armor. HEP reduces packing density in the armor layer near and above the mean water level and increases packing density below it. With HEP, armor units may move in the armor layer, although they are not actually extracted from it. Thus, when HEP occurs, armor-layer poro...

This paper describes the design requirements and restrictions of two different Cubipod armored breakwaters, as well as the 3D hydraulic stability, overtopping and placement tests carried out to validate the final designs. The breakwaters are located on the Mediterranean and Atlantic coasts of Spain. Double-layer and single-layer Cubipod armored bre...

Numerous concrete armor units (CAUs) are designed to be placed randomly. For randomly-placed CAUs, armor porosity and armor unit randomness affect hydraulic stability and breakwater performance during service time. Armor porosity is rarely taken into consideration in small-scale tests; however, armor porosity is directly related to armor constructi...

Van Gent et al. (2007) utilizaron la mayor parte de los ensayos del proyecto europeo CLASH (ver Verhaege et al., 2003) para entrenar una red neuronal (en los sucesivo CLNN) capaz de predecir el rebase en una gran variedad de estructuras. La red neuronal CLNN utiliza 15 parámetros de entrada para definir las condiciones de oleaje a pie de dique y la...

Recommended design KD are associated to implicit global safety factors to Initiation of Damage (IDa) and Initiation of Destruction (IDe). Zero-damage criterion is valid for double-layer armors of massive CAUs, but single-layer armors require a lower-than-zero damage criterion. A simple methodology is proposed to calculate design KD for Cubipod armo...

Single- and double-layer Cubipod armors were considered in the preliminary design of the San Andrés breakwater (Port of Malaga, Spain). 2D and 3D hydraulic stability and overtopping tests for single- and double-layer Cubipod armors were carried out as well as realistic 3D placement tests using a small-scale crawler crane and pressure clamps. The lo...

Armor porosity and armor unit randomness are much easier to control in small-scale models constructed by hand than in prototype. Differences between design and prototype armor porosities and design and armor unit randomness can generate significant model effects. This paper describes realistic 3D placement tests with cube and Cubipod CAUs, using a...

A new maritime vertical structure based in the concept of multi-cell circuit (Medina et al., 2010) is presented to improve the antireflective performance for wave reflection of wind waves and oscillations associated with intense storms, resonance waves in port basins, etc. The large-scale laboratory results show a good performance of the multi-cell...

Most concrete armor units (CAUs) are designed to be placed randomly; however, CAUs can also be placed uniformly, patterned or oriented (Dupray and Roberts, 2009). When CAUs are not randomly placed, special attention is given to the placement technique, construction monitoring and the differences between small-scale models and prototypes. When CAUs...

This paper describes a series of small-scale tests which examined the influence of armor porosity on overtopping. The cube and Cubipod armored models corresponded to the Punta Langosteira Breakwater (A Coruña, Spain) during construction were tested, where the primary layer is not in place and the crest freeboard is much lower. During construction,...

A new semi-empirical model is used to estimate the coefficient of reflection for single- and double-perforated chambers in Jarlan-type breakwaters. This semi-empirical model is based on a potential flow theoretical model which was modified with specific, empirical formulas to obtain a much better agreement with the experimental tests. Single-chambe...

This paper describes a series of small-scale tests which examined the influence of armor porosity on overtopping. The cube and Cubipod armored models corresponded to the Punta Langosteira Breakwater (A Coruña, Spain) during construction, when the primary layer is not in place and the crest freeboard is much lower. Overtopping rates for incomplete c...

This paper presents a new low-reflectivity quay wall caisson based on the formation of cell circuits. The cell circuit lengths can be adapted to the specific wave climate conditions at the construction site to obtain the best performance. Results from physical model tests of conventional and cell circuit caissons are described, as well as the const...

The structural strength of concrete armor units (CAUs) is a key factor in the design and construction of armor layers for large mound breakwaters. This paper describes the prototype drop tests carried out to assess the structural strength of conventional cube and Cubipod CAUs. Low intensity overturning tests, high intensity free fall tests and extr...

The paper presents a comparison of the stability of concrete cube armour and Cubipod armour in a breakwater roundhead with slope 1:1.5, exposed to both 2-D (long-crested) and 3-D (short-crested) waves. The model tests were performed at the Hydraulics and Coastal Engineering Laboratory at Aalborg University, Denmark. The model tests showed that Cubi...

This paper presents a new low-reflectivity quay wall caisson based on the formation of cell circuits. The cell circuit lengths can be adapted to the specific wave climate conditions at the construction site to obtain the best performance. Results from physical model tests of conventional and cell circuit caissons are described, as well as the const...

Mound breakwaters topped with a crown wall are the most common kind of breakwater on Spanish coasts. The purpose of the crown wall is to reduce wave overtopping and the concrete volume of the armour layer. Crown wall stability is necessary to carry out the different operations involved in port activities, sliding being the main failure mode. This r...

The Ploeg and Funke TYPE E double-actuated wavemaker has been calibrated at the CEPYC-CEDEX Laboratory in Madrid, Spain. TYPE E double-actuated wavemakers are capable of operating as piston-only, hinged-only, or simultaneously as both piston and hinged wavemakers. An eigenfunction expansion for the fluid motion generated by a generic planar wavemak...

The structural strength of concrete armor units (CAUs) is a key factor in the design and construction of armor layers for large mound breakwaters. This paper describes the prototype drop tests carried out to assess the structural strength of conventional cube and Cubipod CAUs. Low intensity overturning tests, high intensity free fall tests and extr...

The handling procedure and placement grid of concrete armor units (CAUs) are the key construction factors of armor layers. This paper analyzes conventional cube and Cubipod CAUs which are handled by pressure clamps and placed randomly. Two methodologies for small-scale blind construction of armor layers in laboratories are compared using a Cartesia...

In this paper the performance of cube and Cubipod armor units is compared through a variety of laboratory and prototype experiments. The hydraulic stability of armor layers of cubes and Cubipods is contrasted by analyzing 2D and 3D small scale experiments in three different laboratories using similar non-breaking and non-overtopping cross sections....

A method has been developed to estimate wave overtopping discharges for a wide range of coastal structures. The prediction method is based on Neural Network modelling. For this purpose use is made of a data set obtained from a large number of physical model tests (collected within the framework of the European project CLASH, see e.g. [Steendam, G.J...

Full-scale wave run-up measurements have been carried out on the Zeebrugge rubble mound breakwater in the frame of the EU-funded OPTICREST project. Wave run-up has been measured by a run-up gauge and by a so-called spiderweb system. The dimensionless wave run-up value Ru2%Hm0 measured in Zeebrugge equals 1.77 for Iribarren number xi(om) = 3.63. An...

A clear difference between full-scale wave run-up measurements and small-scale model test results had been noticed during a MAST 11 project. This finding initiated a thorough study of wave run-up through the European MAST III OPTICREST project. Full-scale measurements have been carried out on the Zeebrugge rubble mound breakwater. This breakwater h...

In this paper a new failure mode affecting the armor layer of mound breakwaters is presented, the Heterogeneous Packing (HeP) failure mode, which tends to reduce the packing density of the armor layer near the still water level (SWL) without extracting armor units but only moving slightly within the armor layer. Moreover, a new method to measure di...

Experimental coefficients of reflection (CR) corresponding to one-, two- and three-chamber caisson models of the Jarlan-type breakwater are presented. Breakwater models with single-chamber show CR<40% in the range 0.1< B/L <0.3, similar to CR estimated by formula obtained during PROVERBS project. Experimental CR is compared to the formula given by...

An upgrade of the time-domain method for separating incident and reflected waves, LASA-FN, is presented. This upgrade involves the use of multiple sensors to perform the separation of the incident and reflected waves. The equations of a fully nonlinear wave model are used to calculate pressure and velocity at any point of the fluid, and the surface...