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Yapılan yüksek lisans çalışması, Jarlan tipi dalgakıranların; diğer bir değişle tekli perfore duvarların, fiziksel deneyler ve sayısal modeller üzerinden hidrolik performansının incelenmesi ile bu tip deniz duvarlarının niteliksel anlaşılabilirliğini arttırmayı amaçlamaktadır.Bu çalışmada sayısal modelin sınanması amacıyla, iki-boyutlu bir dalga havuzunda, yedi yeni laboratuvar deneyi yapılmıştır. Yeni laboratuvar deneyleri Yıldız Teknik Üniversitesi, Kıyı ve Liman Laboratuvarı'nda yapılmıştır. Deneylerde kullanılan iki boyutlu dalga kanalı 26m uzunluğunda, 1m genişliğinde ve 1m yüksekliğindedir. Kanala bağlı aktif sönümleme özelliği bulunan bir piston tipi dalga üreticiyle düzenli dalgalar üretilmiş ve su yüzey seviyesi kanal boyunca yer alan yedi dalga ölçerle kaydedilmiştir. Perfore duvar modeli pleksiglas malzemeden üretilerek kanalın sonuna, kör duvarın önüne yerleştirilmiştir.Yapılan sayısal modeller sonucunda, yüzey profillerinin yere ve zamana göre değişimleri, hızları ve yansıma değerleri elde edilmiştir. Sayısal modelleme için açık kaynak kodlu bir modelleme programı olan OpenFOAM kullanılmıştır. OpenFOAM birçok karmaşık fiziksel fenomeni çözebilecek açık kaynak kodlu sayısal bir modelleme programıdır. Bu çalışmada sıkıştırılamayan sıvılar için üç boyutlu, sonlu hacim yöntemiyle serbest su yüzeyi hesaplayan InterFoam çözücüsü kullanılmıştır. Sayısal model ağı kare elemanlardan oluşmakta ve bu elemanların boyutları kanal boyunca 10x10 mm ile 5x5 mm arasında değişmektedir.Fiziksel deney sonuçları sayısal modelin doğrulamasında ve kalibrasyonunda kullanılmıştır. Sayısal model ve fiziksel deney sonuçları serbest yüzey profilleri, ortalama partikül hızları ve yansıma katsayıları üzerinden karşılaştırılmaktadır. Sayısal ve fiziksel model sonuçları arasında serbest yüzey seviyeleri, partikül hızları ve yansıma katsayıları bakımından büyük oranda eşleşme sağlanmıştır. Sayısal modelin genel olarak yüzde 90'ın üzerinde bir isabetle fiziksel modeli simule ettiği görülmüştür. This master thesis aims to improve the quantitative understanding of the hydraulic performance of Jarlan Type breakwaters; in other words, single perforated vertical walls; by examining hydraulic performance through physical modelling and numerical simulations.Seven, laboratory physical model experiments were conducted in this study in a numerical 2-D wave flume to verify the numerical model. These new laboratory experiments were carried out at the Coastal and Harbour Engineering Laboratory of Yildiz Technical University. Experimental setup of two-dimensional wave flume is 26m long, 1m wide and 1m height. It has a piston-type wave generator with an active absorption system, which was used to generate regular waves and surface elevations were recorded along the flume with seven resistive wave gauges during each experiment. The water depth was 0.5m during the tests. As the representative of the breakwater, perforated Plexiglas breakwater was installed at the end of the flume.Numerical models were simulated to obtain the detailed spatial and temporal variations of the surface elevations, velocities, and the reflection coefficients. OpenFOAM (Open Field Operation and Manipulation) modelling library has been used for numerical models. OpenFOAM is an open-source numerical toolbox capable of solving various complex physical phenomena like wave generation. In this study, InterFoam solver has been used, it is a 3-D finite volume solver for two incompressible fluids, incorporating the Volume of Fluid (VOF) method. The numerical model domain comprises square-shaped mesh elements which sizes are changing throughout the channel between 10x10 mm and 5x5 mm.Experimental data is used to validate and calibrate the numerical model. Results of the numerical modelling and physical tests are compared with theoretical data in terms of surface elevation, average particle velocities and reflection coefficients. Results show a great match with the surface elevations, the average particle velocity and reflection coefficients. Overall between laboratory experiment and numerical model results an accuracy above 90% was obtained. 140

Wave slamming on vertical breakwaters cause a sudden, impulsive load that may cause a caisson to slide on its foundation. Alternatively, geotechnical failure may occur in the subsoil. This paper investigates whether simple analytical solutions, accounting only for the sliding along the caisson–foundation interface, can be utilized to properly determine the deformations of the breakwater. Comparisons are made with results obtained by numerical models that include the material response of the soil. Firstly, a computational model is suggested that assumes a fully drained behavior of the subsoil. Secondly, a fully coupled dynamic pore-water-flow model is introduced. The computational examples clearly demonstrate that the deformations of the soil as well as the pore pressures must be accounted for in order to get a reliable prediction of caisson deformations during wave impact.

This paper presents results on loading acting on an innovative caisson breakwater for electricity production. The work reported here is part of the European Union Sixth Framework programme priority 6.1 (Sustainable Energy System), contract 019831, titled "Full-scale demonstration of robust and high-efficiency wave energy converter" (WAVESSG). Information on wave loadings acting on Wave Energy Convert (WEC) Seawave Slot-Cone Generator (SSG) exposed to extreme wave conditions are reported. The SSG concept is based on the principle of overtopping and storing the wave energy in several reservoirs placed one above the other. Comprehensive 2D and 3D wave tank model tests were carried out at the Department of Civil Engineering, Aalborg University (Denmark) in the 3D deep water wave tank. The model scale used was 1:60 of the SSG prototype at the planned location of a pilot plant at the west coast of the island Kvitsøy near Stavanger, Norway. The research study is intended to be of direct use to engineers analyzing design and stability of the pilot plant. This paper presents results on loading acting on an innovative caisson breakwater for electricity production. The work reported here is part of the European Union Sixth Framework programme priority 6.1 (Sustainable Energy System), contract 019831, titled "Full-scale demonstration of robust and high-efficiency wave energy converter" (WAVESSG). Information on wave loadings acting on Wave Energy Convert (WEC) Seawave Slot-Cone Generator (SSG) exposed to extreme wave conditions are reported. The SSG concept is based on the principle of overtopping and storing the wave energy in several reservoirs placed one above the other. Comprehensive 2D and 3D wave tank model tests were carried out at the Department of Civil Engineering, Aalborg University (Denmark) in the 3D deep water wave tank. The model scale used was 1:60 of the SSG prototype at the planned location of a pilot plant at the west coast of the island Kvitsøy near Stavanger, Norway. The research study is intended to be of direct use to engineers analyzing design and stability of the pilot plant.

The paper deals with the analysis of the overall stability of caisson breakwaters exposed to impulsive wave loadings, in particular regarding sliding failure and failure in the subsoil. A comparison is made between prediction of sliding distances by a simple onedimensional (1-D) dynamic analysis and a dynamic two-dimensional finite-element analysis based on the ABAQUS code. Only the last method includes the deformation characteristics of the rubble foundation and sand subsoil. It is shown that the simple 1-D analysis somewhat underestimates the horizontal sliding distance of the caisson. Stability calculations based on equivalent static loads are discussed as well and it is concluded that foundation slip failure cannot be realistically analysed by such a method in the case of impulsive loadings. The paper deals with the analysis of the overall stability of caisson breakwaters exposed to impulsive wave loadings, in particular regarding sliding failure and failure in the subsoil. A comparison is made between prediction of sliding distances by a simple onedimensional (1-D) dynamic analysis and a dynamic two-dimensional finite-element analysis based on the ABAQUS code. Only the last method includes the deformation characteristics of the rubble foundation and sand subsoil. It is shown that the simple 1-D analysis somewhat underestimates the horizontal sliding distance of the caisson. Stability calculations based on equivalent static loads are discussed as well and it is concluded that foundation slip failure cannot be realistically analysed by such a method in the case of impulsive loadings.

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2009, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2009, Bu çalışmada tsunami tipli uzun boylu dalgaların düşey yüzlü kıyı yapısı olan kesonlar üzerindeki basınç etkisinin deneysel olarak incelenmesi ve kesonların Marmara denizinde tsunamilere karşı nasıl davrandığı üzerinde çalışılmıştır. İ.T.Ü. Hidrolik Laboratuarında tsunami dalgasının keson yapı üzerindeki basınç etkisini belirlemek için tsunami kanalında bir deney düzeneği kuruldu. Farklı su derinliklerinde korumalı ve korumasız olarak yapılan deneylerde su derinliği az olan yapılarda daha büyük basınçlar oluşmaktadır. Tsunami dalgalarına karşı koyabilecek kıyı yapıları tasarlarken su seviyesi ve üzerindeki yüzeylerin doğru projelendirilmesi çok önem arzetmektedir. Marmara denizinde muhtemel bir tsunami durumunda keson yapıların kullanılmasının herhangi bir mahzuru olmadığı belirlenmiştir., The purpose of this study is to determine the effects of tsunami waves generated by earthquakes on the vertical coastal structures on Marmara Sea Coast. A tsunami is a series of very long wavelength waves caused by sudden displacement of the sea floor as a result of any tectonic activity. The effects of tsunami waves caused by earthquakes on caisson structures in the Marmara Region are investigated, under which tsunami risk will be determined and rehabilitated. In addition, the protection systems for coastal structures subjected to the possible effects of tsunami waves will be developed. At the end of the study, coastal structures building codes against tsunamis will specially be developed and prepared., Yüksek Lisans, M.Sc.

This paper discusses a new type of Wave Energy Converter (WEC) named Seawave Slot-Cone Generator (SSG). The SSG is a WEC of the overtopping type. The structure consists of a number of reservoirs one on the top of each others above the mean water level in which the water of incoming waves is stored temporary. Using this method practically all waves, regardless of size and speed are captured for energy production. In each reservoir, expressively designed low head hydro-turbines are converting the potential energy of the stored water into electrical power. A key to success for the SSG will be low cost of the structure. The wave forces on the main structure can be estimated using experiences from coastal protection structures, but the differences between the structures are so large that more reliable knowledge on the wave forces is desired. The purpose of the work is to derive information on wave loadings acting on sloping walls constituting the structure. The research is intended to be of direct use to engineers analyzing design and stability of this peculiar kind of coastal structure. This paper discusses a new type of Wave Energy Converter (WEC) named Seawave Slot-Cone Generator (SSG). The SSG is a WEC of the overtopping type. The structure consists of a number of reservoirs one on the top of each others above the mean water level in which the water of incoming waves is stored temporary. Using this method practically all waves, regardless of size and speed are captured for energy production. In each reservoir, expressively designed low head hydro-turbines are converting the potential energy of the stored water into electrical power. A key to success for the SSG will be low cost of the structure. The wave forces on the main structure can be estimated using experiences from coastal protection structures, but the differences between the structures are so large that more reliable knowledge on the wave forces is desired. The purpose of the work is to derive information on wave loadings acting on sloping walls constituting the structure. The research is intended to be of direct use to engineers analyzing design and stability of this peculiar kind of coastal structure.

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2008, Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2008, Bu doktora tez çalışmasında eğimli kıyı yapılarına göre daha yüksek yansıma, daha yüksek tırmanma ve daha yüksek dalga yükleri ortaya çıkaran düşey yüzlü kıyı yapılarının, sayılan bu dezavantajlarının azaltılabilmesi amacıyla geliştirilmiş bir önyüz konfigürasyonu tanımlanmış, bu özelliklerdeki bir yapı için imal edilen fiziksel model üzerinde düzenli ve düzensiz dalgalarla deneyler gerçekleştirilmiştir. Önerilen bu yapı akım odacıklı keson olarak adlandırılmıştır ve tam sakin su seviyesinde bir levha ile ayrılmış iki sığ odacığı bulunan kısmi delikli önyüze sahip bir keson formundadır. Deney sonuçlarına göre dalga yansıması, tırmanması ve dinamik dalga yükleri boyutsuz parametreler cinsinden ifade edilerek yapının performansı değerlendirilmiştir. Bu sonuçlara göre bu yapının yansıma katsayısı düzenli dalgalarda 0,1 düzensiz dalgalarda da 0,5 değerlerinin altına kadar inmiştir. Ayrıca boyutsuz olarak türetilen dalga itkisi ve dinamik dalga momentinin, eşdeğer bir düz düşey yüzeyli yapıya göre bu gelişmiş yapıda %35~%25 mertebesinde azaltılabildiği görülmüştür. Bulunan deneysel sonuçlara ve yapılan gözlemlere göre, önerilen yapının oldukça etkili biçimde gelen dalganın enerjisini sönümleyebildiği sonucuna varılmıştır. Daha sonra üst ve alt odacıkların enerji sönümleme mekanizmaları ile ilgili olarak potansiyel akım ve lineer dalga kabulleriyle birtakım kuramsal incelemeler yapılmış, bu incelemelerle geliştirilen yaklaşım deney sonuçları ile karşılaştırılmıştır. Bu iki grup sonuç arasında genel bir uyum gözlenmiş, bunun yanında akım odacıklı kesonun dalga sönümleme performansının kuramsal yaklaşımla hesaplananın ötesinde etkili olduğu yargısına varılmıştır. Ayrıca bu keson sadece belli bir periyottaki gelen dalgayı değil, üst odacığı sayesinde oldukça geniş bir periyot aralığını sönümleyebilmektedir. Bu noktada üst odacık genişliği yeteri kadar uzun seçilirse, yalnızca düz düşey yüzlü yapılara kıyasla değil, dalgayı odacığı içindeki rezonans özellikleriyle sönümleyen klasik tipteki perfore dalgakıranlara göre de daha avantajlı bir yapı elde edilebilmektedir., With this PhD thesis study, a new type of vertical structure configuration is proposed in order to diminish the general disadvantages of vertical faced coastal structures such as high reflection, high run-up/overtopping and higher horizontal wave force and moment compared to the sloped structures. This newly proposed structure, called flow-chambered caisson, is in the form of a perforated faced caisson breakwater that has two chambers separated just at the mean sea level by a slab-like plate. Experiments were conducted on a physical model constructed in the proposed configuration, using regular and irregular waves; and performance of the structure is evaluated deriving the wave reflection, wave run-up, horizontal wave force and wave moment in the form of dimensionless parameters. Results show that the reflection coefficient of flow-chambered caisson decreases down to 0.1 and 0.5, respectively under regular and irregular waves. Besides the dimensionless horizontal wave force and wave moment were seen to be reduced down to 25%-35% compared to an equivalent plain faced vertical structure. Thus, this newly proposed structure is considered to dissipate the incident wave energy effectively. Afterwards, theoretical approaches under assumptions of liner wave and potential flow were used to define the energy dissipation mechanism of upper and lower chambers; then the calculated results were compared with the experimental ones. It was seen that there is a general agreement between calculated and measured results; yet, the performance of the flow-chambered caisson under wave attack is higher than calculated. Furthermore, this caisson structure can dissipate waves not only at a specific period, but at a wider-range owing to its upper chamber. If constructed with a sufficiently wide upper chamber, the flow chambered caisson is not only superior to the plain faced structures, but also may have significant advantages compared to the classic perforated breakwaters that has only resonant dissipation., Doktora, PhD

This paper addresses wave forces applied to vertical caisson breakwaters. Design diagrams are proposed to evaluate the reduction of the breaker wave force with increasing horizontal length of the units. A model in 1:100 scale of a typical Italian vertical breakwater was tested under multidirectional waves, causing mainly spilling and occasionally plunging breakers, in the CRF-LSF (Wallingford, UK) wave basin. Seven adjacent modules were instrumented with synchronized force transducers. Pulsating and breaking loads were distinguished on the basis of the frequency content and the spatial correlation of the force per unit length was fitted to a single or a double bell shaped distribution. The experimental autocorrelation function for pulsating loads agrees with theoretical solutions; for breaking waves it has a Taylor microscale which is approximately 7% of wavelength, only slightly dependent on spreading, and it goes to zero at great distances; it does not fall rapidly to zero possibly due to the residual correlation of wave troughs. The reduction factor of the load per unit span is hence derived following the argument developed by Taylor for random movements. The effect of wave obliquity is modeled describing the lack of correlation with a simple cosine function. This paper addresses wave forces applied to vertical caisson breakwaters. Design diagrams are proposed to evaluate the reduction of the breaker wave force with increasing horizontal length of the units. A model in 1:100 scale of a typical Italian vertical breakwater was tested under multidirectional waves, causing mainly spilling and occasionally plunging breakers, in the CRF-LSF (Wallingford, UK) wave basin. Seven adjacent modules were instrumented with synchronized force transducers. Pulsating and breaking loads were distinguished on the basis of the frequency content and the spatial correlation of the force per unit length was fitted to a single or a double bell shaped distribution. The experimental autocorrelation function for pulsating loads agrees with theoretical solutions; for breaking waves it has a Taylor microscale which is approximately 7% of wavelength, only slightly dependent on spreading, and it goes to zero at great distances; it does not fall rapidly to zero possibly due to the residual correlation of wave troughs. The reduction factor of the load per unit span is hence derived following the argument developed by Taylor for random movements. The effect of wave obliquity is modeled describing the lack of correlation with a simple cosine function.

The paper presents results from numerical simulations performed with the objective of identifying optimum design safety levels of conventional rubble mound and caisson breakwaters, corresponding to the lowest costs over the service life of the structures. The work is related to the PIANC Working Group 47 on "Selection of type of breakwater structures". The paper summaries results given in Burcharth and Sorensen (2005) related to outer rubble mound breakwaters but focus on optimum safety levels for outer caisson breakwaters on low and high rubble foundations placed on sea beds strong enough to resist geotechnical slip failures. Optimum safety levels formulated for use both in deterministic and probabilistic design procedures are given. Results obtained so far indicate that the optimum safety levels for caisson breakwaters are much higher than for rubble mound breakwaters. The paper presents results from numerical simulations performed with the objective of identifying optimum design safety levels of conventional rubble mound and caisson breakwaters, corresponding to the lowest costs over the service life of the structures. The work is related to the PIANC Working Group 47 on "Selection of type of breakwater structures". The paper summaries results given in Burcharth and Sorensen (2005) related to outer rubble mound breakwaters but focus on optimum safety levels for outer caisson breakwaters on low and high rubble foundations placed on sea beds strong enough to resist geotechnical slip failures. Optimum safety levels formulated for use both in deterministic and probabilistic design procedures are given. Results obtained so far indicate that the optimum safety levels for caisson breakwaters are much higher than for rubble mound breakwaters.

Because breakwaters belong to the most important and costly coastal structures it is of importance to optimise the design with respect both to function and lifetime costs. The paper presents a short discussion on choice of type of breakwater and functional aspects. The main content of the paper is an analysis of the optimum safety level for rubble mound breakwaters. Because breakwaters belong to the most important and costly coastal structures it is of importance to optimise the design with respect both to function and lifetime costs. The paper presents a short discussion on choice of type of breakwater and functional aspects. The main content of the paper is an analysis of the optimum safety level for rubble mound breakwaters.

ÖZET Kıyılar toplumlar tarafından çeşitli şekillerde kullanılmakla birlikte en geniş kullanımı deniz ticareti, turizm ve balıkçılık gibi amaçlarla olmaktadır. Bu faaliyetlere katılan gemiler ve küçük tekneler (yatlar, balıkçı tekneleri vb.) dalga, akıntı, fırtına ve buz gibi dış etkenlere karşı korunmak amacıyla korunmuş bölgeler ararlar. Bu tip tabii veya yapay olarak korunmuş bölgelere barınak adı verilir. Diğer taraftan korunmuş bölgelerde eğer gemilerin çeşitli ihtiyaçları karşılanıyorsa, bakım ve onarımları yapılıyor veya inşaa edilebiliyorsa, yükleme ve boşaltma hizmetleri veriliyorsa ve depolama imkanları mevcutsa bu tip bölgelere liman adı verilir. Yeni yapılacak veya varolup da geliştirilecek bir limanın planlanmasına başlarken dikkat edilmesi gereken en önemli faktörler; optimum ekonomi, optimum emniyet ve optimum estetiktir. Liman planlaması; yer seçimi (yer araştırması, zemin araştırması), liman boyutlarının ve hizmetlerinin belirlenmesi (liman trafiği, gemilerin tip ve boyutları, yanaşma yeri gereksinimleri), genel liman taslağı şeklinde üç ana fazda gerçekleştirilmektedir. Yanaşma yerleri bir limanın iç yapı elemanlarındandır. Yanaşma yerlerinin denize doğru uzananlarına iskele, kıyıya paralel olarak inşaa edilenlerine rıhtım denir. Yanaşma yerleri projelendirilirken zemin parametreleri, deniz taban eğimi, yanaşacak gemi boyutları ve yanaşma yeri arkasında kalan depolama alanları, yükleme boşaltma yerleri göz önüne alınır. Çalışmaya konu olan L tipi, beton bloklu ve kesonlar kabul edilen aynı yükler altında, aynı zemin parametreleriyle depremli ve depremsiz haller için boyutlandırılmış ve DLH'nın birim fiyatları esas arınarak yaklaşık maliyetleri hesaplanmıştır. Bu işlemler farklı derinliklerde tekrar edildikten sonra ekonomik kıyaslamaları yapılarak hangi tip yanaşma yerinin daha ekonomik olduğu tespit edilmiştir. Bu çalışmanın sonucunda deprem etkisi de göz önüne alındığında, en ucuz yanaşma yapısının L tipi rıhtım olduğu belirlenmesine rağmen, uygulamada her zaman bu yapının ekonomik olacağı anlamına gelmemelidir. Çünkü zemin,yapı tipi seçiminde önemli bir faktördür. Ayrıca büyük boyutlardaki L tipi bloklarda taşıma ve kaldırma problemi söz konusudur, buna karşın kesonlar yüzdürülerek yerine yerleştirilebilmektedir. Anahtar Kelimeler : Beton blok tipi rıhtım, 1 tipi rıhtım, keson, maliyet, ekonomi. ıx ABSTRACT Coast are used by people for various purposes but the most common usage is made like sea trade, tourism and fishing. The ships and the small boats(yachts and fishing boats etc.) which are taking part of this activity, try to find protected areas to beware of external factors like waves, currents, storm and icing. This type natural and artificial protected area is called harbour. On the other hand, if the ships' various requirements are provided, ships' maintenance and repair is made or the ship could be builded, handling service is given and storage facilities are existed in this protected areas then this type of area is called port. The most importanat factors in planning of the port to build or to develop are; optimum economy and optimum safety. Port planning is made in three steps. They are; choosing place(place research, soil research), determining port size and services(port traffic, types and size of the ships, berthing place requirements), port's general plan. Berthing places are internal structures of a port. Berthing place which is extended towards the sea is called pier and which is builded parellel to the coast line is called quay wall. When designing a berthing place, soil parameters, sea bed slope, size of the ships, storage sites behind the berthing place and handling facilities should be take into account. L type, concrete block type and caissons which are the subject of this thesis are dimensioned with same acceptable loads and same soil parameters for both state of earthquake and state of without earthquake and approximate cost is estimated by DLH's cost rates. This process is repeated for different depths and with economic analogy, it is determined that which type is the most economic. Althogh it is determined that L type quay wall is the most economic with state of earthquake, in practice it may not be. Because soil type is an important factor for planning of structure. Further more carrying and handling is a problem with big sized L type blocks. But on the other hand the caissons are could be fixed by floating. Keywords : Concrete block type quay, 1 type quay, caisson, cost, economy. x 139

in ÖZET Bu çalışma iki boyutlu dalga kanalında keson dalgakıran kullanılarak yapılan deney sonuçlarının incelenmesini içerir. Deney çeşitli deniz koşullarını temsil eden düzensiz dalgalar üretilerek gerçekleştirilmiştir. Deney ölçeği 1/40 olup, bir düşey yüzeyli ve üç ayrı eliptik yüzeyli olmak üzere dört ayrı keson dalgakıran bu çalışmada kullanılmıştır. Çalışmanın kapsamı iki aşamada değerlendirilebilir. Birinci aşama dalgakırankarın hidrolik özelliklerinin araştırılmasını içerir. Burada yapılara etki eden tasarım yükleri gösterilmiş, elliptik yüzey nedeniyle azalan şok basınçların mertebesi sonuç olarak sunulmuştur. Ayrıca düşey yüzlü dalgakıran için çesşitli basınç hesap yöntemleri denenmiş, Goda yönteminin en isabetli sonucu verdiği belirlenmiştir. Çalışmanın ikinci aşaması ise fouirer serileri yardımıyla hesaplanan spektral analizler kullanılarak, random süreçteki zaman serisinin istatistiksel düzenliliklerinin farklı bir matemetiksel grafik kompozisyonda görülmesi sağlamaktır. Aslında bu analizlerde iki aşamada değerlendirilmiştir. Birinci aşamada tek tek hesaplanan spektral yoğunluk fonksiyonlarını aynı grafik ortamında birleştirelerek, ortak salınımın gerçekleştiği frekanslar belirlenmiş, dalga -basınç arasındaki doğrusallık araştırılmıştır, ikinci aşamada ise çapraz-ilişki fonksiyonları yardımıyla iki farklı seri arasındaki ilişki ve bağımlılık araştırılmıştır. Varılan sonuçlar ise şöyle sıralanabilir. Düşük frekanslarda iki sinyal arasındaki bağımlık daha yüksektir. Yüksek frekanslara doğru gidildikçe doğrusal (linear) ilişkiler azalır. İki seri arasındaki ilişki düzeni dalgaların amplifikasyonu ve yansıma şekillerinden etkilenir, bu durum farklı istasyonlardaki dalga kayıtlarından gözlenebilir. İki seri arasındaki ilişki ve enerjinin değişimi duvar boyunca farklıdır. Duvar boyunca yukarıdan aşağıya doğru gidildikçe iki seri arasındaki ilişki doğrusallasın n ABSTRACT In this study, horizontal wave force on caisson breakwaters is examined for various sea states based on simulated wave records. 1/40 tests were carried out in a two-dimensional wave channel. During the experiments a vertical and three different elliptical model caissons were used. The model caissons were subjected to irregular waves containing both breaking and non-breaking waves. The results were presented in two categories. The first category displayed the hydraulic characteristics of the model caissons. The impulsive pressure reduction due to the elliptical wall is presented. The second category of the study was focused on the spectral characteristics between wave and horizontal wave pressure acting on standard caisson. The main purpose was to determine the correlation and dependence between two series for various cases in the frequency domain. The processes were carried out with spectral density and cross-correlation functions where the major aim was to describe the distribution of energy per unit of frequency. The following major results were obtained. The dependence between two series differs along the frequency axis. Low frequencies indicate strong dependence between two series while higher frequencies indicates week. The amplified and reflected energy affects the correlation pattern where can be detect from the wave gauge stations. The correlation and variation of energy differs along the vertical wall. The non-linearity decreases upper to lower transducers because lower transducers are more correlated with wave than upper. 165

The paper presents a new system for implementation of target reliability in caisson breakwater designs by means of partial safety factors. The development of the system is explained, and tables of partial safety factors are presented for important overall stability failure modes related to caisson structures placed on bedding layers and high rubble mound foundations with underlaying sand and clay subsoils.

The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamic of Structures" financially supported by the Danish Technical Research Council, during the period of January '97 to December '97. The tests were carried out in the 3D wave basin at the Hydraulics and Coastal Engineering Laboratory, Aalborg University. The objective of the study was to asses the effects of wave obliquity and multidirectionality on the wave induced loading and overtopping on caisson breakwaters situated in breaking seas. Regarding the wave forces only minor differences between breaking and non breaking waves in deep water were observed, and it was found that the prediction formula of Goda also seems to apply well for multidirectionally breaking waves at deep water. The study on wave overtopping showed that the 3D wave overtopping formula suggested by Franco et al., 1995b, predicts the wave overtopping reasonable well for both non breaking and breaking waves at deep water.

In extension of the work done at the Hydraulics and Coastal Engineering Laboratory, Dept. of Civil Engineering, Aalborg University, Denmark, described in Grønbech et al., 1997, laboratory tests has been performed investigating wave loading and overtopping on caisson breakwaters in multidirectional breaking seas.

This document has been prepared as a part of the dissemination of results of the MCS-Project (Contract No. MAS2-CT92-0047) which was led by the University of Hannover (Coordinator: H. Oumeraci) within the 2nd Research Programme of the European Union (EU) on Marine and Science Technology. The support of the EU and the cooperation with the EU Scientific Officer Ch. Fragakis are gratefully acknowledged. The following universities and institutes contributed to this document: Delft Geotechnics, Norwegian Geotechnical Institute, Aalborg University, Hannover University, Danish Hydraulic Institute and University of Essen. The foundation aspects of caisson breakwaters are described. Special attention is paid to the dynamic response of the foundation to wave impacts, generation of pore pressures in the subsoil, degradation by repetitive loading and the interaction between all these aspects. Several design levels are distinguished, varying from feasibility studies to research. The feasibility and preliminary design levels are discussed extensively, including a description of the most relevant models and illustrations with the help of example structures. The document may serve as a tool for the drafting of design guidelines and as a framework for future research, for which recommendations are given.

This repor concerns experiments carried out as a combined LIP-MAST-TAW PROJECT DURING May to July, 1994, in the Vinje-Basin at Delft Hydraulics