bluuebunny/crossref_metadata_2025 huggingface dataset:
MORPHOLOGICAL MODELING OF LOW-DUNE BARRIER HEADLAND SYSTEM CHANGES DUE TO HURRICANE FORCING
Authors: Johnson Cody , Chen Qin
Published: February 2019

Coastal barrier landforms serve as the first line of defense against oceanic and meteorological forces. Landward infrastructure and ecosystems, without these barriers, would be significantly more at risk to the flooding and wave forcing caused by extreme storms. Widespread recognition of this function has prompted coastal managers to adopt systematic restoration programs. As an exemplar, the Caminada Headlands (CH) Beach and Dune Restoration Project, located adjacent Port Fourchon, Louisiana (LA), USA cost an estimated $220 million USD and restored ~22.5 kilometers of coastline with a 6.4 million m3 sediment placement. Insight into the performance of the CH restoration during future hurricane impacts requires an understanding of the systemâ€™s response to historical storms. In general, the CH experiences high background shoreline erosion rates. Recent historical averages are on the order of 15 m yr-1 [Byres et al., 2017]. This rate may double during active tropical storm seasons, e.g. the year of hurricane Katrina (2005) [Byres et al., 2017] and, at the event time-scale, localized erosion rates spike dramatically as shorelines may translate 100s of meters landward due to dune overwashing and breaching. Calibration of realistic process based morphological models that can accurately simulate these effects require extensive, high fidelity input data. To achieve this end, this study makes use of several monitoring projects in the LA region while employing a coupled XBeach and Delft3D modeling system to simulate the impact of hurricane Gustav (2008) on the CH.
GEOMETRIC CHARACTERISTICS OF WAVE-GENERATED SAND RIPPLES: A FULL-SCALE EXPERIMENTAL STUDY
Authors: Wang Dongxu , Yuan Jing , Madsen Ole S.
Published: February 2019

In the coastal environment, wave-induced sand ripples are usually observed under moderate near-bed flow conditions. Their occurrence significantly changes the local hydrodynamics and sediment transport processes. Over the past few decades, some solid progresses have been made towards understating the ripple dimensions under wave-generated near-bed flows, e.g., O'Donoghue et al. [2006], but very few studies are targeted on the more detailed geometric characteristics, e.g., the generic shape of ripples and the sharpness of ripple crests, which are closely related to the coherent vortex structures. This study is aimed at filling this knowledge gap.
OBSERVATIONS OF BEACH-DUNE MORPHOGOLICAL RESPONSE TO STORM WAVES USING LIDAR BATHYMETRIC MAPPING IN A WAVE BASIN
Authors: Marmoush Ramy Y. , Mulligan Ryan P.
Published: February 2019

Waves during major storms can cause significant changes to coastal morphology (Lee et al., 1998). The beach-dune system is known to be highly vulnerable to erosion when the wave run-up exceeds the threshold of the base of the dune in the collision regime, according to the Storm Impact scale defined by Sallenger (2000). Detailed bathymetric measurements are very difficult to obtain during storms due to the hazardous wave conditions. However, bathymetric surveys can be easily and intermittently performed during smaller scale physical model experiments (e.g., Hamilton et al., 2001) and high resolution can be achieved using laser scanning with Light Detection and Ranging (LIDAR) sensors (Smith et al., 2017). In the present study, a laboratory experiment of beach-dune morphology change is conducted in a rectangular wave basin that has recently been used to simulate erosion of a 2-dimensional sand dune (Berard et al., 2017). The objective of the present study is to investigate the 3-dimensional morphologic response of a sand beach-dune system to storm waves approaching at an oblique angle.
SCOUR MECHANISM INDUCED BY PROPELLER FLOW NEAR A QUAY WALL
Authors: Yuksel Yalcin , Tan Ilayda , Celikoglu Yesim , Atik Taha
Published: February 2019

Increasing ship dimensions in recent years cause structural instability due to the scouring problem during berthing and unberthing maneuver of the vessels.

The propeller jet has 3D flow area and high velocities that may cause erosion problem around the berthing structures in three ways. These are; a) On a slope, b) At the toe of vertical wall, c) Around piles.

In general scour problems are investigated by using physical modeling. Propeller jet induced the scour in front of the wall has been well studied in the past (Hamill et al. (1999), Ryan et al. (2013(a)), Ryan et al. (2013(b))).

In this study, propeller jet flow was considered to investigate the seabed scour mechanism with and without vertical quay wall conditions and their comparisons were made. Three different distances of the propeller from the wall at Xw=0.7 m, 0.35 m and 0.175 m were tested for different clearances at G=0.1 m and 0.15 m on sand bed of d50=0.052 mm to give an extensive definition for scour depth estimation.
MODELING SHEET FLOW UNDER BREAKING WAVES ON A SURF ZONE SANDBAR
Authors: Kim Yeulwoo , Mieras Ryan C. , Cheng Zhen , Hsu Tian-Jian , Puleo Jack A.
Published: February 2019

Wave-driven sediment transport is one of the main drivers of beach morphodynamics. However, the creation of a comprehensive numerical model remains to be a challenging task due to complex mechanisms associated with unsteadiness and free-surface effects. Particularly for highly non-linear and skewed-asymmetric breaking waves, the boundary layer approximation (i.e., assuming horizontal pressure gradient is equal to local free-stream acceleration) is questionable. Moreover, wave-breaking-induced turbulence may approach the bed and further enhance sediment transport. Thus, a numerical model that can resolve the entire water column from the bottom boundary layer to the free-surface can be a powerful tool to understand wave-driven sediment transport.
IMPACTS OF CHANNEL DEEPENING ON SEDIMENT TRANSPORT MECHANISMS IN A MESOTIDAL ESTUARY
Authors: Zorndt Anna , KÃ¶sters Frank
Published: February 2019

Carefully assessing the environmental impacts of human interventions in estuaries on sediment transport and morphodynamics has become increasingly important due to the high ecological importance of these systems. Man-made changes are typically quantified with numerical sediment transport models. However, setting up these models and more importantly interpreting their results requires a profound knowledge of the natural system and present-day transport processes. This contribution focusses on the mechanisms of sediment transport in a mesotidal estuary and discusses possible impacts of a channel deepening on those mechanisms and their expected impact on long-term changes on sediment transport. The processes are described on the basis of field data and simulations.
LONG-TERM MORPHOLOGICAL EVOLUTION MODEL
Authors: Johnson Bradley , McNinch Jesse
Published: February 2019

Nearshore morphology models predicting storm-scale erosion have been in use for the past several decades. These empirical tools typically focus on a single time-scale, which limits the utilization. For example, models developed to predict cross-shore storm erosion are poorly suited for longer-term simulations that include the beach recovery between events and gradients in longshore transport. Herein, the one-dimensional model CSHORE is extended to include shoreline change associated with along- shore variation in transport. A comparison of model predictions with long-term shoreline data from South Carolina demonstrate reasonable agreement with both erosion and accretion.
THE EFFECTIVE METHOD OF BEACH NOURISHMENT PLACEMENT
Authors: Kim Hyun Dong , Aoki Shin-ichi , Kobayashi Nobuhisa , Onaka Susumu
Published: February 2019

When erosion occurs, sandy beach cannot maintain the sufficient sand width and the foreshore slope becomes steeper by the frequent erosion effect. As a result, the beach is trapped in a vicious circle of becoming vulnerable by the incident waves. In order to repair or protect the erosive beach, beach nourishment can be used as a countermeasure while minimizing the environmental impacts. However, beach nourishment is not a permanent solution and requires periodic renourishment after several years. To alleviate such problem, minimizing the period of renourishment must be an economical alternative. In that respect, selecting the optimum grain size of the sand for the beach nourishment is very important. Generally, larger grain sized sand is more resistant to the erosion, thus extending the period of renourishment. In addition to selecting the optimum grain size of the sand nourishment, determining the durability as well as maintaining the familiarity of the users of the native sand should be considered.
IMPLICATIONS OF CONSOLIDATION ON BARRIER BEACH STABILITY
Authors: Nicholls Robert J. , Burt Lauren , Smethurst Joel , Thompson Charlotte
Published: February 2019

Barrier beaches often overlie backbarrier deposits composed of poorly consolidated sediments. Hence, they can consolidate significantly if loaded. A retreating barrier beach provides such a load. In the static situation of beach nourishment, the increased load of the raised beach volume will also cause increased consolidation. These can lower beach elevation promoting wave overtopping, overwashing and retreat. However, there is limited research concerning the role of consolidation on the stability of barrier beaches worldwide. This paper focuses on this issue using Hurst Spit on the UK south coast as a study site where consolidation is a known significant process (Nicholls, 1985; Burt et al., 2018). It is a storm beach composed of shingle (pebble and cobble) sediments and formerly retreated at 2 to 3 m/yr, Since the later 1990s it has been more stabilized by a major nourishment (Bradbury and Kidd, 1998), but continues to retreat slowly (Figure 1). A second nourishment phase is now being actively assessed following major damage in the large storm of 14 February 2014. In this context, the role of consolidation has been analyzed via new data collection, consolidation modelling and morphodynamic modelling. This paper presents these results and their implications.
FIELD STUDY ON SEDIMENT TRANSPORT AROUND RIVER MOUTH OPENING AT THE TENRYU RIVER IN JAPAN
Authors: Sasaki Yuya , Sato Shinji
Published: February 2019

The Tenryu River mouth and its surrounding coast, located on the Pacific Ocean side in the central Japan, have been suffered from severe coastal erosion. Although increasing sediment supply from river to coast is planned by sand-bypassing through the upstream dams in near future, a better understanding on morphology change around river mouth is needed to facilitate optimal management of the river mouth. Especially, understanding on sediment transport around the river mouth opening is essential to prevent river mouth closure which leads to many problems. The purpose of this study is to reveal the mechanism of sediment transport around river mouth opening.
WIND TUNNEL TESTS OF HOW COASTAL PLANTS FEEDBACK ON DUNE SHAPE
Authors: Charbonneau Bianca , Casper Brenda
Published: February 2019

Theoretical evolution of a coastal dune system starts at the individual plant level with the formation of bedforms, nebkha and shadow dunes, around plants. Over time, these initial bedforms can evolve into a fully developed foredune and eventually a complex dune system capable of buffering upland coastal areas against high tides and storms. Recent studies suggest that dunebuilding plant species may differ in their sand trapping efficiency and they may support different topographies, building dunes morphologically similar to their own stature â€“ i.e. a taller steeper plant would build a taller and steeper dune. We believe that the bedforms created at the onset of dune evolution, i.e. after a storm or at the backbeach, may carry over through the life of the dune, such that understanding how plant morphology and density affects the initial formation stages of dune morphology is key to optimizing dune management, maintenance, and creation. With ERDC and USGS funding, we built a removable bed unilateral flow wind tunnel to test how the morphology among and within dominant US East coast foredune plants feeds back on bedform creation around individual plants at a baseline of zero (i.e. flat back beach or post storm).
FIELD OBSERVATION OF FINE SEDIMENT TRANSPORT PROCESS AROUND RIVER MOUTHS IN NORTH WESTERN JAVA ISLAND, INDONESIA
Authors: Nakagawa Yasuyuki , Widagdo A. Bagyo , Banno Masayuki , Gumbira Gugum A. , Kosako Taichi , Tamura Hitoshi , Istiyanto Dinar C.
Published: February 2019

Understanding of transport processes of discharged sediment through the river in coastal area is crucial for prediction of coastal bathymetry evolution. In case that fine sediment is dominant in sedimentary system, the transport process becomes complicate with the formation of fluid mud, which may be an important role on the transport and distribution of muddy sediment. The aim of this study is to elucidate the fine sediment dynamics, which may have a key role on the deformation of the deltaic topography around the estuary, in a tropical climate environment where experiences apparent seasonal variation of river discharge due to the wet and dry weather condition.
TEST OF EMPIRICAL SEDIMENT TRANSPORT RELATIONS AGAINST EXPERIMENTAL SWASH DATA UNDER THE NON-CAPACITY MODELING FRAMEWORK
Authors: Hu Peng , Tan Liming , Xie Jiafeng , He Zhiguo
Published: February 2019

Swash sediment transport and beach deformation has received great attention in the past two decades. Quantification of swash-induced sediment transport rate is of vital importance for accurate prediction of beach deformation in the swash zone. Two empirical parameters are involved in this quantification, empirical relations for sediment transport capacity and the bed shear stress that may be used in the former. Since the swash zone is highly unsteady, of short cross-shore distance, sediment transport in this zone may be of high possibility to be lag of the flow variation. Thus we have firstly developed a non-capacity sediment transport model for the swash zone. This model appreciates the fact that the actual sediment transport rate may not be necessarily equal to the sediment transport capacity of the flow. In contrast to traditional capacity models that calculate sediment transport rate using directly empirical relations (Hu et al. 2015), the non-capacity model uses the advection-diffusion equation to calculate depth-averaged sediment concentration firstly, and afterwards compute sediment transport rate as flow depth*velocity*concentration. We have also noted that some empirical relations for sediment transport capacity may predict physically unrealistic high values of sediment concentration in the swash zone. This is attributed to the vanishing water depth in the swash zone, whereas existing empirical relations are developed for relatively large water depths (Hu et al. 2015; Li et al. 2017).
BUILDING A NATIONAL SAND RESOURCE INVENTORY FOR THE US CONTINENTAL SHELF
Authors: Waldner Jeffrey , Reidenauer Jeffrey , Turner Lora , Knorr Paul , Brandt Leighann
Published: February 2019

The future of coastal resilience or restoration plans which implement natural or nature-based features largely depends upon the identification of proximate and compatible offshore sand and gravel material. BOEMâ€™s Marine Minerals Program (MMP) is multi-faceted, focusing on coordinated leasing of sediment for extraction, inventorying sediment resources through geological and geophysical surveys of the Outer Continental Shelf (OCS), and environmental studies and reviews to inform decisions.

However, on a national scale, little is known about the character, quantity, and location of sand resources on the OCS and the habitat it provides for biological communities. BOEM places a high priority on creating a comprehensive national sand resource inventory to meet BOEMâ€™s mandate as stewards of all federal mineral resources on the OCS. This stewardship responsibility will be realized by proactively planning for the increasing demands for OCS resources and emergency needs as they arise.
ANALYTICAL SOLUTION OF BEACH PROFILE RESPONSE TO SEA LEVEL RISE - APPLICATION FOR TECTONIC MOVEMENT IN SENDAI, JAPAN
Authors: Tinh Nquyen Xuan , Tanaka Hitoshi , Larson Magnus
Published: February 2019

Kriebel and Dean (1993) developed a simple approach to quantify the beach profile response to a time-varying sea level. It is based on the equilibrium concept implying that if a beach profile is exposed to a constant wave and water level climate it will attain a specific shape ( i.e., the equilibrium beach profile; EBP). A change in the forcing conditions will make the profile move towards a new equilibrium state, which will be attained if these conditions prevail sufficiently long. For the case of typical sea level rise (SLR), the change in the forcing conditions is slow enough so that the profile has time to adjust towards the EBP at any given time. In this study, new analytical solutions are developed based on the convolution method to describe beachÂ­ profile response to sea water level change.
FIELD STUDY OF CONTRASTING BEACH RECOVERY PROCESSES OBSERVED IN NAMI-ITA and KIRIKIRI COASTS AFTER THE 2011 TOHOKU EARTHQUAKE
Authors: Kojima Y. , Tajima Y. , Matsuba Y. , Shimozono T. , Terasawa T. , Abe K.
Published: February 2019

The 2011 Tohoku Earthquake caused significant shoreline retreat along the northern Pacific coast of Japan and most of the affected beaches have not yet fully recovered even six years after the event. This study investigates overall characteristics of the shoreline change after the event and also investigates contrasting beach recovery processes observed in Nami-ita and Kirikiri coasts.
HYBRID SIMULATION OF COASTAL LOADING ON STRUCTURES
Authors: Baragmage Dilshan S. P. Amarasinghe , Forouzan Bahareh , Shaloudegi Koushyar , Nakata Narutoshi , Wu Weiming
Published: February 2019

Hybrid simulation combines the physical testing and computer modeling to analyze the dynamic responses of structures to external impacts (Hakuno et al., 1969). This relatively novel technique has been widely used in earthquake engineering. In the present study, it is extended to analyze the responses of structures to coastal loadings. This paper concerns mainly on the hydrodynamic loading induced by storm surge and tsunami events.
NUMERICAL SIMULATIONS AND ASSESSMENTS OF PERFORATED BREAKWATERS
Authors: Liu Philip L.-F. , Higuera Pablo
Published: February 2019

In this paper we study the physical processes of regular wave trains impacting on a perforated breakwater. The breakwater consists of an array of vertical rectangular columns and a backwall. We have performed numerical simulations in which reflection coefficients have been calculated based on the Mansard and Funke (1980) theory and compared with laboratory data and analytical solutions (Kakuno et al. 1992, Kakuno & Liu, 1993). The numerical solutions will be further analyzed to describe the hydrodynamic processes, identify the limitations of the analytical theory and the scale effects in the laboratory experiments.
REDUCTION OF THE WAVE OVERTOPPING DISCHARGE AT DIKES IN PRESENCE OF CROWN WALLS WITH BULL NOSES
Authors: Zanuttigh Barbara , Formentin Sara Mizar , Palma Giuseppina , Gaeta Maria Gabriella , Guerrero Massimo , Van der Meer Jenstje W. , Van Doorslaer Koen
Published: February 2019

The effects of climate change with increased sea level and intensity of the extreme storms leads to an increase of the loads and of the expected overtopping at existing seawalls. The inclusion of bull-noses in the design of seawalls seems to significantly reduce the wave overtopping discharge q and may be an effective solution to face climate change while limiting the increase of the seawalls height and the costs. The experimental work by Van Doorslaer et al. (2015), VD hereinafter, is the only systematic study available so far about the effects of bull-noses on the reduction of q. They developed a number of formulae, adopted then by EurOtop (2016), in case the seawall is placed on a dike slope or at the end of a promenade. The work we are proposing here starts from these findings, to analyze a different case: dikes with a finite crest width and an inshore crown wall with and without a bull-nose. The aim is to verify whether the formulae developed by VD can still be used or require some modifications to complete the existing design formulae.
REFINED COASTAL MODELING AND ENGINEERING ANALYSIS FOR THE WRIGHTSVILLE BEACH COASTAL STORM DAMAGE REDUCTION PROJECT
Authors: Wang Zhanxian , Vanderbeke Nicole , Grant Brandon , Bedsole Layton
Published: February 2019

In an effort to enhance the Coastal Storm Damage Reduction (CSDR) project at Wrightsville Beach (WB), NC, New Hanover County authorized a refined coastal modeling study in partnership with the Town of Wrightsville Beach. The purpose of the modeling analysis includes the review of potential design betterments that may increase the projectâ€™s storm protection benefits.
A SIMILARITY PARAMETER FOR BREAKWATERS: THE MODIFIED IRIBARREN NUMBER
Authors: Clavero Maria , Folgueras Pedro , Diaz-Carrasco Pilar , Ortega-Sanchez Miguel , Losada Miguel A.
Published: February 2019

In the 14th ICCE, Battjes (1974) showed that a single similarity parameter only, embodying both the effects of slope angle and incident wave steepness, was important for many aspects of waves breaking on impermeable slopes, and suggested to call it the "Iribarren number", denoted by "Ir". Ahrens and McCartney (1975) verified the usefulness of Ir to describe run-up and stability on rough permeable slopes. Since then, many researchers applied Ir to characterize and to develop formulae for the design of breakwaters and to verify their stability. On the other hand, depending on their typology, breakwaters reflect, dissipate, transmit, and radiate incident wave energy. Partial standing wave patterns are likely to occur at all types of breakwater, thus playing an important role in defining the wave regime in front of, near (seaward and leeward), and inside the breakwater. The characteristics of the porous medium, relative grain size D/L and relative width, Aeq/L2, are relevant magnitudes in that wave pattern (Vilchez et al. 2016), being D the grain diameter, L the wave length and Aeq the porous area per unit section under the mean water level. Aeq/L2 is a scattering parameter controlling the averaged transformation of the wave inside the porous section of the structure. For a vertical porous breakwater (Type A), Aeq is simply B Â· h, and for a constant depth, the scattering parameter is reduced to B/L, which is the relative breakwater width.
EUROTOP OVERTOPPING GUIDANCE APPLIED IN A TOOL TO THE LARGE VARIETY OF COASTAL PROTECTIONS AT ILE DE RÃ‰
Authors: Dugor Jérémy , Van der Meer Jentsje , Baills Julien , Rihouey Didier
Published: February 2019

Ile de RÃ© is a low-lying island located on the western edge of France. The extreme storm Xynthia (February 2010), was one of the most destructive natural disasters in this area, causing severe damages and breaches on coastal protections and one third of the total area of the island was flooded. Storm impact feedback showed that wave overtopping and/or overflow was responsible for more than 60 failures or breaches. From this major event, an important work was undertaken to improve the 100 km of coastal structures. This paper describes the development of a tool, partly based on numerical modelling, that will prioritise coastal structure monitoring by forecasting overtopping discharges and volumes on the different exposed dikes on Ile de RÃ©, regarding different storm parameters and structure characteristics. This tool will supply helpful information to manage the maintenance operations and improvements of this important linear of heterogeneous and sometimes old coastal protections.
THE INFLUENCE OF A CROWN WALL ON WAVE OVERTOPPING OVER RUBBLE MOUND STRUCTURES
Authors: Van Doorslaer Koen , Kortenhaus Andreas , Troch Peter , De Meyere Goele , Vantomme Lieselot
Published: February 2019

The crest of a breakwater is often equipped with a crown wall with multiple functions such as a border of the pedestrian walkway, support of the rubble mound or concrete armour units, and reduction of the wave overtopping over the structure in storm conditions. However, the knowledge on how a crown wall influences the overtopping discharge is yet still limited. EurOtop (2016) advises to take the maximum of the crest freeboard Rc and the armour freeboard Ac in case a crown wall is present, and to use the average between Ac and Rc when no crown wall is present. This advice is based on expert judgement rather than on experimental research. The goal of the present work is to carry out experimental research and confirm or update the advice on overtopping over a crown wall for rubble mound structures.
PRELIMINARY ENGINEERING OF A SEAWALL TO MITIGATE TYPHOON-INDUCED WAVE OVERTOPPING ALONG ROXAS BOULEVARD, MANILA
Authors: Cruz Eric C. , Santos Jose , Cruz Laurenz Luigi
Published: February 2019

Roxas Boulevard is a crucial national road of the urban transport system of Metro Manila. The road is protected from the sea hazards of Manila Bay by Roxas Boulevard Seawall. This gravity-type seawall also protects the important recreational promenade and high-value properties behind the wall. The seawall was overtopped several times by recent strong typhoons. In 2011, it collapsed after storm surges and waves generated by Typhoon Nesat overtopped it and caused substantial flooding of a vast urban area of Manila city just behind the seawall. It was rebuilt quickly after that but only to be overtopped again by severe storm tides and high waves from subsequent strong typhoons. A study was commissioned by the national public works agency DPWH to understand the causative processes and provide basis for suitable mitigating solutions against overtopping of the seawall. This study discusses the typhoon-induced hydrodynamics in Manila Bay and the preliminary engineering undertaken to design one of the engineering interventions that were recommended to mitigate seawall overtopping.
ANALYSIS OF ENGINEERING FEASIBILITY OF AN OPEN PIER AGAINST COASTAL HAZARDS ALONG LUZON ISLAND
Authors: Cruz Eric C. , Inocencio Ismael Aragorn D. , Kasilag II Edgardo P. , Villaflor Laurice Angeli V.
Published: February 2019

As an archipelago, the Philippines highly depends on ports for inter-island trade and commerce. However the country is vulnerable to coastal hazards such as typhoons and tsunamis. To serve the growing demand for commercial cargo transport in the northern region of the countryâ€™s largest island Luzon, an open pier is being proposed to be built along the western seaboard. This paper presents a methodology of carrying out a coastal engineering assessment of the feasibility of an open pier possibly without protective breakwaters. The analysis aims to determine the wave climate of the project coast under prevailing non-storm conditions under which the port is expected to operate. The study also aims to quantify the historical storm tides along the project coast as basis for the vertical siting of the pier structure for engineering design. Finally, a study of the tsunami hazard is undertaken to consider the possible significance of infrequent but potentially catastrophic hazard into the engineering design basis of the pier.
ASSESSMENT OF A NATURE-BASED STRUCTURE TO MANAGE COASTAL DUNE EROSION IN YUCATAN, MEXICO
Authors: Leija Mariana Gonzalez , Lomas Soffa Fregoso
Published: February 2019

In Yucatan , one of the main causes of coastal erosion is the use of "remedy" measures (groins or "espolones") by communities whom refuses to eliminate them (Medellin, 2015, Ruiz,2016). The erosion management approach has been dominated by engineering schemes resulting in beach values degradation and despite the development of recovery programs, no actions for protection/restoration of coastal ecosystems particularly , dunes have never been undertaken. In addition , dune flattening and vegetation elimination are common practices associated to coastal land use. Today , 56.1% of coast lacks of any type of dune/vegetation and 32% of sandy beaches are
DEVELOPMENT OF MULTISCALE MULTIPHYSICS INTEGRATED SIMULATOR FOR TSUNAMI RUNUP CALCULATION COUPLED WITH STRUCTURE ANALYSIS
Authors: Arikawa Taro , Seki Katsumi , Chida Yu , Takagawa Tomohiro , Shimosako Kenichiro
Published: February 2019

The 2011 Great East Japan Earthquake (GEJE) has shown that Tsunami disasters not only cause flooding damage but also can be a phenomenon accompanied by many damage of structures. In order to evaluate the damage of the building due to the tsunami, a three dimensional numerical tank with structure analysis is required, but the calculation cost is very high to calculate from the tsunami source of the tsunami to the inundation zone. Therefore, the purpose of this research is to develop a system that can calculate the destruction of buildings from a wave source of the tsunami in a series and confirm its validity. Specifically, the stability of Tsunami breakwaters in Kamaishi Bay and the seawalls in Otsuchi Bay was investigated.
INFLUENCE OF CROWN-WALL ON WAVE OVERTOPPING PROBABILITY AND PROBABILITY DISTRIBUTION OVER A SEAWALL
Authors: Gu Jiayue , Hu Xin , Liu Shuguang , Ju Quanhe
Published: February 2019

In the past decades, the crest height of the seawall was determined by the allowable average wave overtopping rate q. Franco (1994) concluded that individual wave overtoppingï¼Œparticularly the maximum individual volume, provided a better design method than q, considering the stability of the seawall and the safety of vehicles and people along the coastal area protected by the coastal defense structures. Shanghai, located on the west bank of the Pacific Ocean, is quite sensitive to the risk of storm surges and violent wave overtopping. The crown-wall serves as an engineering measure to reduce the wave overtopping effectively.
THE PREDICTION OF EXTREME VALUE WIND SPEEDS AND WAVE HEIGHTS FROM SATELLITE DATA
Authors: Takbash Alicia , Young Ian
Published: February 2019

The prediction of extreme value (e.g. 1 in 100 year) estimates of wind speed and wave height is an essential element of coastal and ocean engineering design. Despite decades of research on the statistics of extreme values, the consistent limitation faced by practitioners is the requirement for a long (20 plus years) dataset at the location of interest. Long term insitu buoy deployments have started to provide useful records in some geographic locations. Long term numerical model hindcasts have also proved useful. However, buoy deployments are seldom at the location of interest and the accuracy of numerical model hindcasts more than 20 years in the past is questionable. This paper will investigate the use of long-term satellite data sets of wind speed and wave height to provide global estimates of extreme values.
WAVE TRANSMISSION OVER LOW-CRESTED POROUS BREAKWATERS
Authors: Koutrouveli Theofano I. , Dimas Athanassios A.
Published: February 2019

Low-crested (LC) rubble mound breakwaters are used for coastal protection. The main advantage of these structures is their mild aesthetic impact on the natural environment. As the waves approach and transmit over these structures, significant hydrodynamic processes occur in their proximal area, such as wave breaking, wave reflection, wave overtopping and transmission (Garcia et al., 2004). Many researchers have studied the hydrodynamics of flow in the vicinity of such structures, as well as the influence of their geometrical characteristics on the flow field. However, in most studies, the structures are either emerged or submerged, while the case in which the crest level of the breakwaters is at the still water level (SWL) has to be further investigated.
OVERFLOW AND WAVE OVERTOPPING OVER BROAD QUAY WALLS MODELED WITH OPENFOAM
Authors: Vanneste Dieter , Van Hoydonck Wim , Thoon Daphné
Published: February 2019

In the framework of the EU Floods Directive, Flanders Hydraulics Research (FHR) is performing flood modeling studies to evaluate the flood risk along the Belgian coast due to extreme storm surges on the North Sea. Thereto, amongst others, the failure behavior of quay walls in the coastal ports must be determined. Computing the landward non-impulsive wave overtopping discharge over a broad quay, in some cases combined with overflow, on which a flood wall can be present at large distance [O (100 m)] from the front edge poses a particular challenge. This matter, to the authorsâ€™ knowledge, is not covered in existing literature, e.g. the European Overtopping Manual. It is also not possible to apply the method for reduction of wave overtopping over a wide crest according to Verwaest et al. (2010), since it was developed for breaking waves on a shallow foreshore overtopping a sloping dike, requiring the determination of a run-up level. It is clear that the landward water flow on the quay should be investigated in more detail, as it is characterized by bottom friction and possible inertia due interaction with the flow reflected at the flood wall. To this end, the CFD toolbox OpenFOAM is used to model the final discharges at the landward side of the quay.
A PREDICTIVE FUZZY LOGIC MODEL TO BIMODAL WAVE PARTITIONING IN WELSH COASTLINE
Authors: Orimoloye Stephen , Reeve Dominic E. , Karunarathna Harshinie
Published: February 2019

Bimodal seas are usually characterised by the combination of swell and locally generated wind energy. Understanding the percentage of the swell component (SC) and the wind component (WC) partitioned from the energy content of a Wave System (WS) is important in coastal defense design and management. The South Wales and southwest England wave climate is mostly characterised by bimodal wave spectra because they are directly facing the North Atlantic Ocean. In this paper, we describe the application of fuzzy logic to develop an efficient wave partitioning system for bimodal wave energy separation that can be used to characterise the percentage of swell and wind waves in a measured sea state.
SHIP-GENERATED WAVES OVER A COMPLEX BATHYMETRY
Authors: AlmstrÃ¶m BjÃ¶rn , Larson Magnus , Granath Lars , Hanson Hans
Published: February 2019

Problems related to shipping have increased worldwide during the last decades as a result of more traffic travel-ling at higher speeds and using larger vessels. When ships move in a restricted fairway they generate primary (drawdown) and secondary (transverse and divergent) waves (Bertram 2000) that often cause adverse impact to adjacent shores. An example of this is the Furusund fairway in Sweden, which since the 1980â€™s has experienced increased traffic and larger ships. This has resulted in a loss of natural fine sediment habitats along the shores as well as structural damages to piers and jetties (Granath 2015). Furusund is an important fairway into Stockholm, the capital of Sweden, and is located about 25 km north of the city within the Stockholm archipelago. It is mainly trafficked by large ferries (length/width/draft: 200x30x7m). The wind-wave regime in the fairway can be described as a low-energy environment, due to the short fetches and no swell. Hence, ship waves have a significant impact on the shores in terms of bed and bank erosion. This study aims at determining the primary ship wave characteristics and their relationship to ship properties and bathymetric conditions in the Furusund fairway. Measured water levels were collected for this purpose during three months at three locations. Existing empirical formulas for drawdown are evaluated based on the measurements and compared with a new formula derived for the specific fairway. The results are used for designing nature-based protection against ship-generated waves along the shores and to validate analytical and numerical models that can be employed for ship wave generation and propagation.
NUMERICAL SIMULATION OF IRREGULAR WAVES RUNUP ON A BEACH
Authors: Sun Luning , Kennedy Andrew , Kennedy Andrew
Published: February 2019

Breaking wave induced run-up can significantly risk infrastructure in coastal areas. For instance, run-up elevation can cause coastal flooding. Moreover, the momentum flux transported onshore can also exert forces on beaches and coastal structures. This study aims at predicting shoreline forces and inundation depths via numerical simulation as well as better understanding coastal run-up events.
IRREGULAR WAVE MODELLING WITH CFD IN SULAFJORD FOR THE E39 PROJECT
Authors: Wang Weizhi , Kamath Arun , Bihs Hans
Published: February 2019

The E39 project aims at building a continuous ferry-free coastal highway along the west coast of Norway. Sulafjord is one of the fjords where ferries are to be replaced with floating bridges or floating tunnels. The floating structures demand accurate and realistic numerical simulations of the wave propagation and transformation in the fjords. The Norwegian coastline is characterized by dramatic water depth changes and deep water conditions. The coastal water also contains both swells and local wind-generated waves. These conditions, along with series of islands outside the fjords and very irregular coastline, make wave modeling more challenging for this region. Thus, the application of CFD models which provide high-resolution and phase-resolved solutions for complicated wave freesurface is explored. First, the spectral wave model SWAN is used to estimate the wave properties at the inlet of the Sulafjord from offshore wave data. Using the estimated wave data at the inlet as input, a large-scale 3D regular wave CFD simulation is performed using the open-source model REEF3D. Then unidirectional and multi-directional irregular wave CFD simulations are performed to represent a more realistic sea state, using a frequency spectra and a directional spreading function. The statistical properties of the simulated irregular ocean waves at three locations inside the fjord are compared among the CFD simulations and with the spectral wave model. The differences in the simulation results are discussed and studied.
GENERATION OF EXTREME TRANSIENT WAVES IN EXPERIMENTAL MODELS
Authors: Zhang Huichen , BrÃ¼hl Markus
Published: February 2019

The transfer of natural waves and sea states into small- and large-scale model teste contributes to the proper design of offshore and coastal structure. Such shallow-water ocean surface waves are highly nonlinear and subject to wave transformation and nonlinear wave-wave interactions. However, the standard methods of wave generation according to conventional wave theories and wave analysis methods are limited to simple regular waves, simple sea states and low-order wave generation without considering the nonlinear wave-wave interactions. The research project Generation of Extreme Transient Waves in Experimental Models (ExTraWaG) aims to accurately generate target transient wave profile at a pre-defined position in the wave flume (transfer point) under shallow water conditions. For this purpose, the KdV-based nonlinear Fourier transform is introduced as a continuative wave analysis method and is applied to investigate the nonlinear spectral character of experimental wave data. Furthermore, the method is applied to generate transient nonlinear waves as specific locations in the wave flume, considering the nonlinear transformation and interactions of the propagating waves.
VESSEL-INDUCED SURGE MODEL VALIDATION IN A COMPLEX HARBOR USING FIELD MEASUREMENTS AND AIS DATA
Authors: Salcedo Francis , Sharma Abhishek , Fenical Scott , Ledford Gary
Published: February 2019

Large ships moving in narrow waterways generate complex hydrodynamic phenomena, which can cause extreme forces and moments on berthed vessels, and damage shoreline structures and marine habitat. Deep-draft vessels can generate complex phenomena such as bow solitary waves, broken supercritical bore waves, and ship-induced harbor seiche/oscillations. Particular focus is paid in the present paper to simulation and validation of the Vessel Hydrodynamics Longwave Unsteady (VH-LU) modeling system (Fenical et al. 2006) for these complex hydrodynamic phenomena, in particular sloshing and resonance of vessel-induced waves in the complex harbor of Port Canaveral, FL. This paper summarizes two field measurement campaigns and utilization of high-resolution AIS data to provide detailed input for model validation. Analysis indicates that the modeling system is able to reproduce water level oscillations generated by individual vessels, oscillation interactions within the harbor, and interactions between separate basins in the harbor over time. Previous publications have provided limited information on validations performed with the VH-LU modeling system (e.g. Fenical et al. 2011). The model has been shown to accurately reproduce hydrodynamics and berthed vessel forces on tankers in open water conditions, hydrodynamics and loads on berthed Panamax container ships against a vertical quay wall, and supercritical flow and broken bore formation and propagation. This paper will summarize the complete range of model validations with the highest-quality openly available laboratory data, and provide recommendations for future studies and research based on observed needs from practical applications.
EXPERIMENTAL MODELING OF WAVE FORCES AND HYDRODYNAMICS ON ELEVATED COASTAL STRUCTURES SUBJECT TO WAVES, SURGE OR TSUNAMIS: THE EFFECT OF BREAKING, SHIELDING AND DEBRIS
Authors: Lomonaco Pedro , Alam Mohammad Shafiqual , Arduino Pedro , Barbosa Andre , Cox Daniel T. , Do Trung , Eberhard Marc , Motley Michael , Shekhar Krishnendu , Tomiczek Tori , Park Hyoungsu , Van de Lindt John W. , Winter Andrew
Published: February 2019

Coastal communities provide important economic, transport, and recreational services to large numbers of people worldwide. However, these coastal communities are vulnerable to damage by extreme events such as tropical cyclones or tsunamis. Waves and surge, as well as tsunami-wave events, may cause extensive damage to elevated structures through a combination of horizontal and vertical wave and surge-induced forces. Structural elevation has been shown to be a critical variable affecting damage and loss. Recent efforts have been made to retrofit structures or improve coastal protection and damage mitigation plans in coastal communities to increase community resilience. However, to effectively retrofit old structures or design new structures to resist damage due to hurricanes or tsunamis, engineers require an accurate estimation of both the wave hydrodynamics and the resulting loads.
VALIDATION OF UNSTRUCTURED WAVEWATCH III FOR NEARSHORE WAVES
Authors: Smith Jane McKee , Hesser Tyler , Roland Aron , Bryant Mary
Published: February 2019

Unstructured wave model grids in the nearshore coastal region provide flexibility and efficiency to resolve complex shorelines and high-gradient wave zones to drive nearshore circulation, wave setup and wave-driven sediment transport. Recent improvements to the unstructured version of WAVEWATCH III (WW3) (WW3DG 2016) to support nearshore application include an implicit solution scheme and domain decomposition for multi-scale spatial coverage over approximately three orders of magnitude. The hybrid approach to parallelization involves spectral partitioning for advection in geographical space and domain decomposition for spectral advection and the source term integration. The advection part of wave action equation is integrated fully implicitly, and a new convergent action limiter derived from Komen et al. (1994) and Hersbach and Janssen (1999) is applied. New Block-Jacobi and Block-Gauss-Seidel solvers are applied with improved convergence. The purpose of this paper is to evaluate the upgraded unstructured WW3 for nearshore application.
A LABORATORY STUDY ON WAVE OVERTOPPING AT VERTICAL SEAWALLS WITH A SHINGLE FORESHORE
Authors: Salauddin Md , Pearson Jonathan
Published: February 2019

The existing empirical prediction formulae to determine the wave overtopping characteristics are mainly based on the laboratory measurements with the use of an impermeable foreshore slope in front of the structure. Recently, EurOtop (2016), an updated version of previous overtopping manual has been published with revised empirical equations to estimate mean overtopping discharge rates at plain vertical walls with and without foreshore.As past studies were mostly carried out at vertical seawalls on a fixed impermeable bed, little knowledge is available on the performance of these processes at coastal structures on a permeable shingle beach. This study presents the baseline overtopping characteristics at a plain vertical wall on an impermeable 1:20 foreshore slope, and compares the results with existing empirical predictions (EurOtop, 2016). In this paper, only the results on mean overtopping discharge and mean sediment rate at vertical walls are reported.
INTERACTIONS OF WAVES WITH IDEALIZED HIGH-RELIEF BOTTOM ROUGHNESS
Authors: Yu Xiao , Rosman Johanna H. , Hench James L.
Published: February 2019

Interactions between waves and high-relief bottom roughness were investigated using Large Eddy Simulations of oscillatory flow over an infinite array of regularly spaced hemispheres. Simulation results were analyzed using a spatially- and phase-averaged momentum balance to provide insight into how flow-topography interactions affect wave-driven oscillating flows. Phase-averaging was applied first, and then spatial averaging was applied over volumes with horizontal length scales greater than the size of a single solid obstacle but fine enough in the vertical direction that the vertical structure of the dynamics was resolved. Spatial averaging of the momentum equation results in terms that represent drag and inertial forces, and a dispersive stress term that represents a vertical momentum flux induced by the spatial heterogeneity of the phase-averaged flow. These new terms require parameterization in coastal ocean wave and circulation models.
INTERACTIVE AND IMMERSIVE COASTAL HYDRODYNAMIC SIMULATION
Authors: Lynett Patrick J. , Tavakkol Sasan
Published: February 2019

In this presentation, we will discuss the development and application of a GPU-based Boussinesq-type wave model. The novelty of this approach is that it is meant to serve the primary purpose of being interactive â€“ allowing the user to modify the boundary conditions and model parameters as the model is running, and to see the effect of these changes immediately. To accomplish this, the model is coded in a shader language environment, and our physical variables (e.g. ocean surface elevation, water velocity) are represented in the model as textures, which can be rapidly rendered and visualized via a GPU. This software can help scientists better understand nearshore wave dynamics as it allows them to observe wave interactions in real-time and modify the boundary conditions and model parameters as the model is running to see the effect of these changes immediately. The model is named â€œCelerisâ€, and is released under the GNU (open-source, open-access) license.
EXTRATROPICAL STORM GENERATED SWELL INDUCED VULNERABILITY EFFECT ON A TROPICAL ISLAND
Authors: Onat Yaprak , Francis Oceana
Published: February 2019

The high-energy swells in the Northern Pacific are generally due to extratropical cyclones during the winter season. Conserving most of their energy while traveling long distances, strong swells increase the susceptibility of coastal zones of remote islands by increasing their vulnerability. Understanding the vulnerability caused by distant source generated swells allows adaptive attempts to be taken to protect natural, social, cultural and economic assets. The extratropical cyclone trends and its relation to swells requires a need to quantify its effect on island coastlines. The vulnerability is a complex phenomenon that demands multidisciplinary approaches, methods, and data sources to estimates of the impacts objectively. The main problem when it comes to defining vulnerability of small island communities is that even the unforeseen elements affect their susceptibility because they are more prone to the impacts of climatic forcing. Therefore, in this study, we extend an existing approach to quantify how extratropical storm generated swells affect the vulnerability of remotely located tropical islands.