Simulation and Experimental Studies of a Multi-Tubular Floating Sea Wave Damper

Total Page:16

File Type:pdf, Size:1020Kb

Simulation and Experimental Studies of a Multi-Tubular Floating Sea Wave Damper energies Article Simulation and Experimental Studies of a Multi-Tubular Floating Sea Wave Damper Leszek Chybowski ID , Zenon Grz ˛adzieland Katarzyna Gawdzi ´nska* ID Faculty of Marine Engineering, Maritime University of Szczecin, 70-500 Szczecin, Poland; [email protected] (L.C.); [email protected] (Z.G.) * Correspondence: [email protected]; Tel.: +48-914-809-941 Received: 26 March 2018; Accepted: 11 April 2018; Published: 20 April 2018 Abstract: This article explores the issue of shore protection from sea waves and has presented the main methods used for coastal protection. It discusses the construction and operation of the multi-tubular floating sea wave damper that has been developed at the Maritime University of Szczecin by Professor Bolesław Ku´zniewski.This paper presents the results of the research project aimed at creating and examining a prototype of the device. The research aimed to confirm the two hypotheses: “the largest damping force should occur when the damping units are placed at an optimal distance equal to half the length of the wave to be damped” and “a compensation of the horizontal forces caused by the rippling of water should occur in the damping device”. Simulation studies of the behaviour of the device’s buoyancy elements when floating on waves were performed using the ANSYS AQWAWB and AQWA software. The buoyancy components were modelled as TUBE elements with a diameter of 0.11 m and a length of 1.5 m and as triangular and square surface elements. The results of the experimental research and the computer simulation of the operation of the prototype device have also been presented. The external conditions adopted corresponded to the frequency of a wave equal to 0.807 Hz and to the wave height in front of the device which was equal to 0.1 m. Experimental studies were conducted in an auxiliary model basin with dimensions of 60 m × 7 m × 3.12 m at the Ship Hydromechanics Division, Ship Design and Research Centre (CTO S. A.) in Gda´nsk(Poland). The study recorded the distribution of the vertical and horizontal forces acting on the prototype device as well as the wave height both in front of and behind the device. Both hypotheses were proven. Simulation and experimental studies have been summarised. A proposal for future works has also been presented. Keywords: sea waves; damping; shore protection; model basin; load simulation; multi-tubular floating damper; Ku´zniewski’sdamper 1. Introduction Effective protection of the sea shore remains a valid but still unsolved social issue that forms part of the responsibilities of any public authority. The coastal area is a space of human expansion which includes the majority of hydrotechnical facilities. Furthermore, it is estimated that more than 60% of the world’s population inhabit coastal areas [1]. These areas are directly related to many fields of human activity, such as industry, trade, agriculture, fishing and tourism. As a rule, hydrotechnical facilities are structures that are subjected to complex mechanical loadings [2–8], among which of primary importance are the hydrotechnical forces associated with water movement [9,10]. The most important factors that cause water movement in coastal zones are surface waves and wave-driven currents [11–13]. Dynamic phenomena occurring in coastal zones [14], including wind-driven sea waves which are a major cause, contribute to coastal erosion and abrasion [15]. Figure1 shows an overview map of the impact of erosion processes on European sea shores. Particularly great coastal Energies 2018, 11, 1012; doi:10.3390/en11041012 www.mdpi.com/journal/energies Energies 2018, 11, 1012 2 of 20 Energies 2018, 11, x 2 of 20 Energies 2018, 11, x 2 of 20 damage can be observed in Belgium, Denmark, Estonia, France, Spain and Italy. Interesting case Particularly great coastal damage can be observed in Belgium, Denmark, Estonia, France, Spain and studies regarding Mediterranean islands can be found in references [11,12,16]. Italy.Particularly Interesting great case coastal studies damage regarding can be Mediterranean observed in Belgium, islands canDenmark, be found Estonia, in references France, [11,12,16]. Spain and Italy. Interesting case studies regarding Mediterranean islands can be found in references [11,12,16]. FigureFigure 1. ExposureExposure to to coastal coastal erosion erosion in Europe [17]. [17]. Figure 1. Exposure to coastal erosion in Europe [17]. For example, the Polish sea annually claims about 50 hectares of land which have a total value For example, the Polish sea annually claims about 50 hectares of land which have a total value of of 500For million example, zlotys. the The Polish worst sea situationannually isclaims on the about western 50 hectares coast, on of theland Hel which Peninsula have a and total on value the 500 million zlotys. The worst situation is on the western coast, on the Hel Peninsula and on the Vistula Vistulaof 500 millionSpit [1]. zlotys.There areThe areas worst where situation coastal is onregression the western exceeds coast, one on meter the Hel per Peninsulayear. Approximately and on the Spit [1]. There are areas where coastal regression exceeds one meter per year. Approximately 60% to 60%Vistula to 70% Spit of [1]. the There Polish are coastline areas where is exposed coastal to regression erosion caused exceeds by one wave meter movement. per year. EveryApproximately year, the 70% of the Polish coastline is exposed to erosion caused by wave movement. Every year, the country’s country’s60% to 70% territory of the Polishis reduced coastline by about is exposed 340,000 to erosionm2 [18]. caused In recent by wavedecades, movement. more than Every 70% year, of thethe territory is reduced by about 340,000 m2 [18]. In recent decades, more than 70% of the Polish coast has Polishcountry’s coast territory has been is affected reduced by by erosive about processes.340,000 m The2 [18]. average In recent annual decades, rate of more coastline than recession 70% of thein been affected by erosive processes. The average annual rate of coastline recession in the years from thePolish years coast from has 1975 been to affected 1983 was by 0.9erosive m/year. processes. Furthermore, The average it is important annual rate to ofrealise coastline that recessiona coastline in 1975 to 1983 was 0.9 m/year. Furthermore, it is important to realise that a coastline recession at the recessionthe years atfrom the 1975rate ofto only1983 0.10 was m 0.9 per m/year. year means Furthermore, a loss of it land is important area equal to torealise about that 37,000 a coastline m2 per rate of only 0.10 m per year means a loss of land area equal to about 37,000 m2 per year. There are a year.recession There at are the a ratenumber of only of methods0.10 m per of coastalyear means protection a loss whichof land vary area in equal efficiency, to about implementation 37,000 m2 per number of methods of coastal protection which vary in efficiency, implementation and operation costs andyear. operation There are costs a number and level of methods of environmental of coastal protectioninterference which [19–22]. vary A in brief efficiency, overview implementation of the basic and level of environmental interference [19–22]. A brief overview of the basic methods is presented in methodsand operation is presented costs and in Figure level of2. environmental interference [19–22]. A brief overview of the basic Figure2. methods is presented in Figure 2. Figure 2. Technical methods of shore protection [22]. Figure 2. Technical methods of shore protection [22]. Figure 2. The following methods are amongTechnical the most methods popular: of shore protection [22]. The following methods are among the most popular: TheBreakwater—this following methods consists are among of concrete, the most stone popular: or prefabricated structures placed parallel or at anBreakwater—this angle to the consistsshoreline. of concrete,Figure 3 stone shows or prefabricatedexample breakwaters structures placedmade ofparallel patented or at ­ Breakwater—thisprefabricatesan angle to ofthe consists various shoreline. of types. concrete, Figure One stone disadvantage 3 shows or prefabricated example to this structuressolutionbreakwaters is placed the made deepening parallel of patented or of at the an anglewaterprefabricates to thebasin shoreline. directlyof various Figure in types.front3 shows Oneof examplethe disadvantage structure breakwaters fromto this the made solution side of patentedof is the deepeningopen prefabricates sea, ofhuge the of implementationwater basin directly cost and in limitsfront ofto thewater structure exchange from between the sidethe seaof theand openthe areasea, beinghuge protected.implementation cost and limits to water exchange between the sea and the area being protected. Energies 2018, 11, 1012 3 of 20 various types. One disadvantage to this solution is the deepening of the water basin directly in front of the structure from the side of the open sea, huge implementation cost and limits to water Energiesexchange 2018, 11 between, x the sea and the area being protected. 3 of 20 ­ Components installed on the sea bed, below the water surface—barrages, artificial reefs. Components installed on the sea bed, below the water surface—barrages, artificial reefs. The The drawbackdrawback to to these these kinds kinds ofof structures is is the the deepening deepening of ofthe the water water basin basin directly directly in front in frontof of the structurethe structure and the and need the for need maintenance for maintenance and systematic and systematic monitoring monitoring of its of technical its technical condition. ­ Structurescondition. placed in the beach area—plants, fences, brushwood, geotextiles and geosynthetic materials. Structures The disadvantage placed in the of thisbeach type area—plants, of solution isfences, the extent brushwood, of intervention geotextiles in the and natural ecosystemgeosynthetic of the dunes.
Recommended publications
  • Α Ρ Α Ρ Ρ Ρ Cot Cot 1 K H K H M ∆ = ⌋ ⌉
    ARMOR POROSITY AND HYDRAULIC STABILITY OF MOUND BREAKWATERS Josep R. Medina1, Vicente Pardo2, Jorge Molines1, and M. Esther Gómez-Martín3 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 analyzed. The stability number showed a significant 1.2-power relationship with the packing density, similar to what has been found in the literature for other armor units; thus, the higher the porosity, the lower the hydraulic stability. To avoid uncontrolled model effects, the packing density should be routinely measured and reported in small-scale tests and monitored at prototype scale. Keywords: mound breakwater; armor porosity; packing density; armor damage; armor unit; cubic block. INTRODUCTION When quarries are not able to provide stones of the adequate size and price, precast concrete armor units (CAUs) are required for the armor layer protecting large mound breakwaters. The first CAUs, introduced in the 19th century, were massive cubes and parallelepiped blocks with a very simple geometry. Since the invention of the Tetrapod in 1950, numerous precast CAUs with complex geometries have been invented to reduce the cost and to improve the armor layer performance. The overall breakwater construction cost depends on a variety of design and logistic factors, like armor material (reinforced concrete, quality of unreinforced concrete, granite rock, sandstone rock, etc.), armor unit geometry (cube, Tetrapod, etc.), armor unit mass (3, 10, 40, 150-tonne, etc.), casting, handling and stacking equipment, transportation and placement equipment, energy, materials and personnel costs.
    [Show full text]
  • Feasibility Study of an Artifical Sandy Beach at Batumi, Georgia
    FEASIBILITY STUDY OF AN ARTIFICAL SANDY BEACH AT BATUMI, GEORGIA ARCADIS/TU DELFT : MSc Report FEASIBILITY STUDY OF AN ARTIFICAL SANDY BEACH AT BATUMI, GEORGIA Date May 2012 Graduate C. Pepping Educational Institution Delft University of Technology, Faculty Civil Engineering & Geosciences Section Hydraulic Engineering, Chair of Coastal Engineering MSc Thesis committee Prof. dr. ir. M.J.F. Stive Delft University of Technology Dr. ir. M. Zijlema Delft University of Technology Ir. J. van Overeem Delft University of Technology Ir. M.C. Onderwater ARCADIS Nederland BV Company ARCADIS Nederland BV, Division Water PREFACE Preface This Master thesis is the final part of the Master program Hydraulic Engineering of the chair Coastal Engineering at the faculty Civil Engineering & Geosciences of the Delft University of Technology. This research is done in cooperation with ARCADIS Nederland BV. The report represents the work done from July 2011 until May 2012. I would like to thank Jan van Overeem and Martijn Onderwater for the opportunity to perform this research at ARCADIS and the opportunity to graduate on such an interesting subject with many different aspects. I would also like to thank Robbin van Santen for all his help and assistance for the XBeach model. Furthermore I owe a special thanks to my graduation committee for the valuable input and feedback: Prof. dr. ir. M.J.F. Stive (Delft University of Technology) for his support and interest in my graduation work; Dr. ir. M. Zijlema (Delft University of Technology) for his support and reviewing the report; ir. J. van Overeem (Delft University of Technology ) for his supervisions, useful feedback and help, support and for reviewing the report; and ir.
    [Show full text]
  • Capability Statement Coastal Engineering Delta Marine Consultants Delta Marine Consultants
    Capability Statement Coastal Engineering Delta Marine Consultants Delta Marine Consultants Delta Marine Consultants (DMC) was founded in 1978 for the purpose of providing consultancy, project management and engineering design services to clients on a worldwide basis. The company has expertise in the fields of urban infrastructure, large-scale transport infrastructure, ports and harbour development and coastal engineering. The company holds strong links with the construction industry through its parent company, the Royal BAM Group. This contributes to the ability to provide solutions to practical problems and to blend innovation with reliability in design. DMC has been rebranded into ‘BAM Infraconsult’ and is working under that name in the home market. DMC is still used as a trade name for international projects and referred to as such in this Design Capability Statement. DMC has well over 300 employees working in various offices worldwide. The head office is in Gouda (the Netherlands) and apart from several other offices in the Netherlands, local offices are also located in Singapore, Dubai, Jakarta and Perth. DMC is or has been active in a great number of other countries on project basis, often together with BAM contracting companies. Our Core Business Coastal engineering, is one of the core expertise areas of DMC. The interaction between land and water creates complex environments. Coastal areas and river banks have always been important to trade and are therefore vital links in the economic chain. Coastal works, just like ports, are very much influenced by natural phenomena such as tidal change, wave action and extreme weather conditions, which is why they call for specialized expertise.
    [Show full text]
  • Adapting to Climate Change in Coastal Communities of the Atlantic Provinces, Canada: Land Use Planning and Engineering and Natural Approaches
    ADAPTING TO CLIMATE CHANGE IN COASTAL COMMUNITIES OF THE ATLANTIC PROVINCES, CANADA: LAND USE PLANNING AND ENGINEERING AND NATURAL APPROACHES PART 3 ENGINEERING TOOLS ADAPTATION OPTIONS INCENT EYS NG V L , P.E . DANIEL BRYCE ATLANTIC CLIMATE ADAPTATION SOLUTIONS ASSOCIATION SOLUTIONS D'ADAPTATION AUX CHANGEMENTS CLIMATIQUES POUR L'ATLANTIQUE March 2016 Prepared by ISO 9001 Registered Company ADAPTING TO CLIMATE CHANGE IN COASTAL COMMUNITIES OF THE ATLANTIC PROVINCES, CANADA: LAND USE PLANNING AND ENGINEERING AND NATURAL APPROACHES Prepared for ACASA (Atlantic Climate Adaptation Solutions Association) No. AP291: Coastal Adaptation Guidance – Developing a Decision Key on Planning and Engineering Guidance for the Selection of Sustainable Coastal Adaptation Strategies. PART 1 GUIDANCE FOR SELECTING ADAPTATION OPTIONS Saint Mary’s University Lead: Dr. Danika van Proosdij Research Team and Authors: Danika van Proosdij, Brittany MacIsaac, Matthew Christian and Emma Poirier Contributor: Vincent Leys, P Eng., CBCL Limited PART 2 LAND USE PLANNING TOOLS ADAPTATION OPTIONS Dalhousie University Lead: Dr. Patricia Manuel, MCIP LPP Research Team and Authors: Dr. Patricia Manuel, MCIP LPP, Yvonne Reeves and Kevin Hooper Advisor: Dr. Eric Rapaport, MCIP LPP PART 3 ENGINEERING TOOLS ADAPTATION OPTIONS CBCL Limited Lead: Vincent Leys, P Eng. Research Team and Authors: Vincent Leys, P Eng. and Daniel Bryce (formerly CBCL) Reviewers: Alexander Wilson, P Eng., Archie Thibault, P Eng. and Victoria Fernandez, P Eng., CBCL Limited Editing Team: Dr. Patricia Manuel, MCIP, LPP and Penelope Kuhn, Dalhousie University ADAPTING TO CLIMATE CHANGE IN COASTAL COMMUNITIES OF THE ATLANTIC PROVINCES, CANADA: LAND USE PLANNING AND ENGINEERING AND NATURAL APPROACHES PART 3 ENGINEERING TOOLS ADAPTATION OPTIONS CBCL Limited Lead: Vincent Leys, P Eng.
    [Show full text]
  • Coastal and Ocean Engineering
    May 18, 2020 Coastal and Ocean Engineering John Fenton Institute of Hydraulic Engineering and Water Resources Management Vienna University of Technology, Karlsplatz 13/222, 1040 Vienna, Austria URL: http://johndfenton.com/ URL: mailto:[email protected] Abstract This course introduces maritime engineering, encompassing coastal and ocean engineering. It con- centrates on providing an understanding of the many processes at work when the tides, storms and waves interact with the natural and human environments. The course will be a mixture of descrip- tion and theory – it is hoped that by understanding the theory that the practicewillbemadeallthe easier. There is nothing quite so practical as a good theory. Table of Contents References ....................... 2 1. Introduction ..................... 6 1.1 Physical properties of seawater ............. 6 2. Introduction to Oceanography ............... 7 2.1 Ocean currents .................. 7 2.2 El Niño, La Niña, and the Southern Oscillation ........10 2.3 Indian Ocean Dipole ................12 2.4 Continental shelf flow ................13 3. Tides .......................15 3.1 Introduction ...................15 3.2 Tide generating forces and equilibrium theory ........15 3.3 Dynamic model of tides ...............17 3.4 Harmonic analysis and prediction of tides ..........19 4. Surface gravity waves ..................21 4.1 The equations of fluid mechanics ............21 4.2 Boundary conditions ................28 4.3 The general problem of wave motion ...........29 4.4 Linear wave theory .................30 4.5 Shoaling, refraction and breaking ............44 4.6 Diffraction ...................50 4.7 Nonlinear wave theories ...............51 1 Coastal and Ocean Engineering John Fenton 5. The calculation of forces on ocean structures ...........54 5.1 Structural element much smaller than wavelength – drag and inertia forces .....................54 5.2 Structural element comparable with wavelength – diffraction forces ..56 6.
    [Show full text]
  • HODS of COMPUTING SEDIMENTATION in LAKES and RESERVOIRS a Contribution to the International Hydrological Programme, IHP - II Project A
    2 14. 8 5 M E HODS OF COMPUTING SEDIMENTATION IN LAKES AND RESERVOIRS A contribution to the International Hydrological Programme, IHP - II Project A. 2.6.1 Panel Stevan Bruk, Rapporteur Unesco, Paris lO:£/q.C?SSrf& llsn-. ^2>l Unesco, Paris ~-F::\r>Y J^TCRX'AT.'OfvAL REFERENCE C7.X~RF: ; aAAi. vAT::v.'v ;;;;r/ METHODS OF COMPUTING SEDIMENTATION IN LAKES AND RESERVOIRS A contribution to the International Hydrological Programme, I HP - II Project A. 2.6.1 Panel r- ••••' — - -,-•• „ _ Stevan Bruk, Rapporteur '; t^'^S-^' -^::V WA'r--R SUPPLY | A.\U b -.' -n„. ,,._.,, ,....•"""••" ' ^s Hague .SKI 3iS£ February 1985 The Yugoslav National Committee for the International Hydrological Programme contributed to the printing Of this book Unesco'1985 Printed by the Printing Department of the Jaroslav Cemi Institute for the Development of Water Resources P.O. Box 530,11000 Belgrade, Yugoslavia Preface Although the total amount of water on earth is generally assumed to have Remained virtually constant, the rapid growth of population, together with the extension of irrigated agriculture and industrial development, are stressing the quantity and quality aspects of the natural system. Because of the increasing problems, man has begun to realize that he can no longer follow a "use and discard" philosophy ~ either with water resources or any other natural resources. Asa result, the need for a consistent policy of rational management of water resources has become evident. Rational water management, however, should be founded upon a thorough understanding of water availability and movement. Thus, as a contribution to the solution of the worlds water problems, Unesco, in 1965, began the first world-wide programme of studies of the hydrological cycle - the International Hydrological Decade (IHD).
    [Show full text]
  • Hydraulic Structures General
    Course CIE3330 Hydraulic Structures General November 2009 Faculty of Civil Engineering and Faculty Geosciences Contributions to these lecture notes were made by: dr. ir. S. van Baars ir. K.G. Bezuyen ir. W.Colenbrander ir. H.K.T. Kuijper ir. W.F. Molenaar ir. C. Spaargaren prof. ir. drs. J.K. Vrijling Delft University of Technology Artikelnummer 06917290037 CT3330 Hydraulic Structures 1 (empty page) ©Department of Hydraulic Engineering Faculty of Civil Engineering ii Nov 2009 Delft University of Technology CT3330 Hydraulic Structures 1 TABLE OF CONTENTS PREFACE..................................................................................................................................................... v READER TO THESE LECTURE NOTES .................................................................................................... v THE COURSE HYDRAULIC STRUCTURES 1 – CT3330 ......................................................................... vi 1. Introduction to Hydraulic Structures................................................................................................. 1-1 1.1 Piers ................................................................................................................................................. 1-2 1.2 Artificial islands ................................................................................................................................ 1-5 1.3 Breakwaters ....................................................................................................................................
    [Show full text]
  • Offshore Wind Farms: Their Impacts, and Potential Habitat Gains As Artificial Reefs, in Particular for Fish
    THE UNIVERSITY OF HULL Offshore wind farms: their impacts, and potential habitat gains as artificial reefs, in particular for fish being a dissertation submitted in partial fulfilment of the requirements for the Degree of MSc In Estuarine and Coastal Science and Management By Jennifer Claire Wilson BSc (Hons) Marine and Freshwater Biology, University of Hull September 2007 1 Abstract Due to both increased environmental concern and an increased reliance on energy imports, there has been a significant increase in investment in, and the use of, wind energy, including offshore wind farms, with twenty-nine developments built or proposed developments off the United Kingdom’s coastline alone. Despite the benefits of cleaner energy generation, since the earliest planning stages there have been concerns about the environmental impacts of wind farms, including fears for bird mortalities and noise affecting marine mammals. Many of these impacts have now been shown to have fewer detrimental effects that originally expected, and therefore the aim of this report is to try and determine whether another environmental concern – that of a loss of seabed due to turbine installation – is as significant as originally predicted. Using details of the most commonly used turbine foundation, the monopile, and the methods of scour protection used around their bases – gravel, boulders and synthetic fronds – calculations for net changes in the areas and types of habitat were produced. It was found that gravel and boulder protection provide the maximum increase in habitat surface area (650m2 and 577m2 respectively), and although the use of synthetic fronds results in a loss of surface area of 12.5m2, it would be expected that the ecological usefulness and carrying capacity of the area would increase, therefore it would still be environmentally beneficial.
    [Show full text]
  • Programme and Book of Abstracts, a Receipt of the Registration Fee, and Souvenirs
    Table of Contents Page Welcome Message 1 Committees and Sponsors 2-6 General Information 7-9 APAC2011 Programme at a Glance 10-12 APAC2011 Oral Sessions 13-25 APAC2011 Poster Sessions 26-27 Keynote Lectures 29-72 Book of Abstracts 73-139 Welcome to APAC2011 It is our great pleasure to welcome you to this 6th International Conference on Asian and Pacific Coasts (APAC2011) and to the great city of Hong Kong. The Conference, hosted by The University of Hong Kong during December 14–16, 2011, aims to provide a platform where engineers and researchers can keep abreast of the current scientific and technological advancements in coastal and port-related research and practice. The response to our Call for Papers announced in March 2011 was very heartening. We ended up receiving more than 300 submissions from more than 30 countries around the world. After peer review, some 250 papers have been accepted for presentation at the Conference. This volume contains the APAC2011 Conference Programme and the Book of Abstracts. The programme consists of 6 keynote lectures, 4 invited lectures, 10 contributions to the Special Session on the 2011 East Japan Tsunami, and 237 other contributions arranged in various oral and poster sessions. These presentations cover a wide range of topics related to coastal, ocean and harbour engineering, such as beach erosion and morphodynamics, climate change and sea level rise, coastal management and shore protection, estuaries and ports, hydrodynamics of offshore and coastal structures, marine ecology and environment, marine and offshore wind energy, seawater intrusion, sediment transport, tsunami and storm surges, waves and tides, wastewater disposal and water quality, and so on.
    [Show full text]
  • Stability Design of Coastal Structures (Seadikes, Revetments, Breakwaters and Groins)
    Note: Stability of coastal structures Date: August 2016 www.leovanrijn-sediment.com STABILITY DESIGN OF COASTAL STRUCTURES (SEADIKES, REVETMENTS, BREAKWATERS AND GROINS) by Leo C. van Rijn, www.leovanrijn-sediment.com, The Netherlands August 2016 1. INTRODUCTION 2. HYDRODYNAMIC BOUNDARY CONDITIONS AND PROCESSES 2.1 Basic boundary conditions 2.2 Wave height parameters 2.2.1 Definitions 2.2.2 Wave models 2.2.3 Design of wave conditions 2.2.4 Example wave computation 2.3 Tides, storm surges and sea level rise 2.3.1 Tides 2.3.2 Storm surges 2.3.3 River floods 2.3.4 Sea level rise 2.4 Wave reflection 2.5 Wave runup 2.5.1 General formulae 2.5.2 Effect of rough slopes 2.5.3 Effect of composite slopes and berms 2.5.4 Effect of oblique wave attack 2.6 Wave overtopping 2.6.1 General formulae 2.6.2 Effect of rough slopes 2.6.3 Effect of composite slopes and berms 2.6.4 Effect of oblique wave attack 2.6.5 Effect of crest width 2.6.6 Example case 2.7 Wave transmission 1 Note: Stability of coastal structures Date: August 2016 www.leovanrijn-sediment.com 3 STABILITY EQUATIONS FOR ROCK AND CONCRETE ARMOUR UNITS 3.1 Introduction 3.2 Critical shear-stress method 3.2.1 Slope effects 3.2.2 Stability equations for stones on mild and steep slopes 3.3 Critical wave height method 3.3.1 Stability equations; definitions 3.3.2 Stability equations for high-crested conventional breakwaters 3.3.3 Stability equations for high-crested berm breakwaters 3.3.4 Stability equations for low-crested, emerged breakwaters and groins 3.3.5 Stability equations for submerged breakwaters
    [Show full text]
  • Guidance for Coastal Protection Works in Pacific Island Countries
    Guidance for coastal protection works in Pacific island countries DESIGN GUIDANCE REPORT This report is published by the Pacific Region Infrastructure Facility (PRIF). PRIF is a multi-development partner coordination, research and technical assistance facility that supports infrastructure development in the Pacific. PRIF member agencies include the Asian Development Bank (ADB), Australian Department of Foreign Affairs and Trade (DFAT), European Investment Bank (EIB), European Union (EU), Japan International Cooperation Agency (JICA), New Zealand Ministry of Foreign Affairs and Trade (NZMFAT), and the World Bank. The views expressed in this report are those of the authors and do not necessarily reflect the views and policies of ADB, its Board of Governors, the governments they represent, or any of the other PRIF member agencies. Furthermore, the above parties neither guarantee the accuracy of the data included in this publication, nor do they accept responsibility for any consequence of their application. The use of information contained in this report is encouraged, with appropriate acknowledgement. The report may only be reproduced with the permission of the PRIF Coordination Office on behalf of its members. Acknowledgements The report, based on a research study published by PRIF in February 2017 – Affordable Coastal Protection in the Pacific islands - was prepared by Dr Tom Shand, Coastal Engineer, Tonkin and Taylor and Matt Blacka, Water Research Laboratory, University of New South Wales, under the guidance of Lorena Estigarribia, Technical Assistance Officer, PRIF Coordination Office, and Oliver Whalley, Transport Analyst, World Bank. The Asian Development Bank provided administrative support. The authors thank the PRIF project team, members of the PRIF committees and working groups, external technical reviewers and editors.
    [Show full text]
  • 2006 Bruce Vandermeer.Pdf
    A COMPARISON OF OVERTOPPING PERFORMANCE OF DIFFERENT RUBBLE MOUND BREAKWATER ARMOUR Tom Bruce1, Jentsje van der Meer2, Leopoldo Franco3 and Jonathan M. Pearson4 This paper describes a major programme of tests to establish better the influence of armour roughness and permeability on overtopping. Specifically, the tests determined the relative difference in overtopping behaviour for various types of armour units. Roughness factors γf for the database and for use in the neural network prediction of overtopping were determined for rock (two layers), cubes (single-layer and two-layers), Tetrapod, Antifer, Haro, Accropode, Core-Loc and Xbloc. INTRODUCTION The overtopping database of the CLASH project (Steendam et al., 2004) contains more than 10000 test results on wave overtopping at coastal structures worldwide and is therefore considerably larger than initially foreseen. The database was used as input for a neural network which resulted in a generic prediction method for overtopping at coastal structures (Pozueta et al., 2004, Van der Meer et al., 2005). Interim analysis of the overtopping database indicated that there were some “white spots” where further model tests would be advantageous. Test programmes to fill these “white spots” were devised. This paper describes a major programme of 2D model tests to better establish the influence of roughness or permeability on overtopping. Specifically, the objective was to determine the relative difference in overtopping behaviour for various types of armour units leading to roughness factors γf for the database and for use in the neural network prediction of overtopping. TECHNICAL BACKGROUND Run-up on sloping structures What is a good definition of relative overtopping? A complete smooth structure could be considered as a structure giving maximum overtopping (no friction, no porosity).
    [Show full text]