To see the other types of publications on this topic, follow the link: Breakwater.
Journal articles on the topic 'Breakwater'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Breakwater.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Isaacson, Michael, Neal Whiteside, Robert Gardiner, and Duncan Hay. "Modelling of a circular-section floating breakwater." Canadian Journal of Civil Engineering 22, no. 4 (August 1, 1995): 714–22. http://dx.doi.org/10.1139/l95-082.
Full textAbstract:
The physical and numerical modelling of a circular cross-section floating breakwater subjected to normal and obliquely incident regular waves is described. The transmission coefficient, breakwater motions, and mooring line forces were measured in two- and three-dimensional laboratory tests for a range of wave conditions and breakwater parameters. The experimental results are compared with results of a numerical model based on linear two-dimensional wave diffraction theory. The performance of the breakwater is summarized and compared with that of a rectangular-section breakwater. Possible modifications to improve the breakwater's performance characteristics are considered. Key words: coastal structures, floating breakwaters, hydrodynamics, moorings, waves.
2
Jiang, Lai, Jisheng Zhang, Linlong Tong, Yakun Guo, Rui He, and Ke Sun. "Wave Motion and Seabed Response around a Vertical Structure Sheltered by Submerged Breakwaters with Fabry–Pérot Resonance." Journal of Marine Science and Engineering 10, no. 11 (November 21, 2022): 1797. http://dx.doi.org/10.3390/jmse10111797.
Full textAbstract:
This paper presents the results from a numerical simulation study to investigate wave trapping by a series of trapezoidal porous submerged breakwaters near a vertical breakwater, as well as the seabed response around the vertical breakwater. An integrated model, based on the volume-averaged Reynolds-averaged Navier–Stokes (VARANS) equations is developed to simulate the flow field, while the dynamic Biot’s equations are used for simulating the wave-induced seabed response. The reflection of the wave energy over the submerged breakwaters, caused by the vertical breakwater, can be reserved, indicating that the existence of the submerged breakwaters in the front of the vertical breakwater can either provide shelter or worsen the hazards to the vertical breakwater. Numerical examples show two different modes under the Fabry–Pérot (F–P) resonance condition of the wave transformation, namely the wave reflection (Mode 1) and the wave trapping (Mode 2). The distance between the submerged breakwaters and the vertical breakwater, is a key parameter dominating the local hydrodynamic process and the resultant dynamic stresses around the vertical breakwater. The numerical results indicated that more submerged breakwaters and a higher porosity of submerged breakwaters will obviously dissipate more wave energy, and hence induce a smaller wave force on the rear vertical breakwater and liquefaction area around the vertical breakwater.
3
Teh, Hee Min, Vengatesan Venugopal, and Tom Bruce. "HYDRODYNAMIC PERFORMANCE OF A FREE SURFACE SEMICIRCULAR PERFORATED BREAKWATER." Coastal Engineering Proceedings 1, no. 32 (January 29, 2011): 20. http://dx.doi.org/10.9753/icce.v32.structures.20.
Full textAbstract:
The increasing importance of the sustainability challenge in coastal engineering has led to the development of free surface breakwaters of various configurations. In this study, the hydrodynamic characteristics of a perforated semicircular free surface breakwater (SCB) are investigated for irregular wave conditions. The hydrodynamic performance of the breakwater is evaluated in the form of transmission, reflection and energy dissipation coefficients, which are then presented as a function of the relative submergence depth (D/d) and the relative breakwater width (B/Lp), where D = the depth of immersion, d = the water depth, B = the breakwater width and Lp = the wavelength corresponding to the peak wave period. It is found that the wave attenuation ability of the SCB model improves with the increase of D/d and B/Lp. The SCB performs better as an energy dissipater than as a wave reflector. Based on the analysis of measured data, some empirical equations are proposed to predict the performance of the breakwater under varying submergence depths. The behaviour of wave transformation around and within the breakwater’s chamber is discussed. Also, the measured horizontal wave forces acting on the SCB are reported.
4
Nguyen, Nu Thi, Son Truong Bui, and Dung Tien Le. "The potential of using fine rock for replacing soft soil in construction of a breakwater at Chan May port." Journal of Mining and Earth Sciences 61, no. 4 (August 31, 2020): 75–85. http://dx.doi.org/10.46326/jmes.2020.61(4).08.
Full textAbstract:
Breakwater is an important construction in Chan May port. The construction of breakwaters faces many difficulties due to the soft soil layer with a thickness of more than ten meters and located under the sea level. Breakwater is unstable as well as high of settlement. Therefore, the soft soil under the breakwater was replaced by fine rock. The results show that it is feasible to replace soft soil by fine rock when constructing breakwater in the sea. This is the basis for the design of soft ground treatment for breakwaters in Vietnam.
5
Filianoti, Pasquale G. F., and Luana Gurnari. "A Field Experiment on Wave Forces on an Energy-Absorbing Breakwater." Energies 13, no. 7 (March 27, 2020): 1563. http://dx.doi.org/10.3390/en13071563.
Full textAbstract:
The U-OWC is a caisson breakwater embodying a device for wave energy absorption. Under the wave action, the pressure acting on the upper opening of the vertical duct fluctuates, producing a water discharge alternatively entering/exiting the plant through the U-duct, formed by the duct and the chamber. The interaction between incoming waves and the water discharge alters the wave pressure distribution along the wave-beaten wall of this breakwater compared with the pressure distributions on a vertical pure reflecting wall. As a consequence, the horizontal wave forces produced on the breakwater are also different. A small scale U-OWC breakwater was put off the eastern coast of the Strait of Messina (Southern Italy) to measure the horizontal wave force. Experimental results were compared with Boccotti’s and Goda’s wave pressure formulas, carried out for conventional upright breakwaters, to check their applicability on the U-OWC breakwaters. Both models are suitable for design of U-OWC breakwaters even if they tend to overestimate by up to 25% the actual horizontal loads on the breakwater. Indeed, the greater the absorption of the energy is, the lower the wave pressure on the breakwater wall is.
6
Duan, Wenyang, Shupeng Xu, Qianlong Xu, R. Cengiz Ertekin, and Shan Ma. "Performance of an F-type floating breakwater: A numerical and experimental study." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 231, no. 2 (October 13, 2016): 583–99. http://dx.doi.org/10.1177/1475090216673461.
Full textAbstract:
Floating breakwaters are structures with large ratio of length to breadth. The profile of an floating breakwater is the key to the hydrodynamic properties of it. In this work, a new kind of an F-type floating breakwater is presented. Its profile is asymmetric and looks like the English letter “F.” We present both numerical and experimental findings on this F-type floating breakwater. Based on linear potential-flow theory, first, the boundary-element method is presented to study the interaction problem of a two-dimensional floating body with waves. Following that, the two-dimensional experiments are conducted in a wave flume to measure the diffracted and radiated waves, the resulting transmission and reflection coefficients, and the motion responses of the F-type floating breakwater. It is shown that the experimental data are, in general, in good agreement with the numerical predictions. The transmission coefficients that are measured and calculated are under 0.5 when the ratio of B/λ (the ratio of model breadth to wavelength), when the F-type floating breakwater is fixed, is larger than 0.18. The ratio of B/λ, when the F-type floating breakwater is allowed to slide vertically only, is larger than 0.2 and the ratio of B/λ, when the F-type floating breakwater is allowed to rotate and slide, is larger than 0.22. To understand how the profile geometry can affect the performance of the F-type floating breakwater, a parametric study of the F-type floating breakwater’s main dimensions, including its profile breadth, draft, and angle, is conducted on the wave transmission coefficient. It is found that the transmission coefficients are particularly sensitive to the change in draft for certain sea conditions. These results are important since seeking the optimal principal dimensions can ensure minimum volume of displacement, thereby using less material and reducing the cost of construction sharply.
7
Murali, K., S. S. Amer, and J. S. Mani. "Dynamics of Cage Floating Breakwater." Journal of Offshore Mechanics and Arctic Engineering 127, no. 4 (May 27, 2005): 331–39. http://dx.doi.org/10.1115/1.2073347.
Full textAbstract:
Floating breakwaters have potential applications in protecting minor ports and harbors such as fisheries and recreational harbors, where-in stringent tranquillity requirements are not warranted. In field applications of the existing floating breakwaters, limitations are imposed due to their large relative width (ratio between breakwater width and wave length) requirements to achieve desirable tranquillity level. This relative width requirement is greater than 0.3 for the existing floating breakwaters. To overcome the above drawback associated with the existing system a new configuration for a floating breakwater is derived, which could yield the desired performance with minimum relative width requirement. The floating breakwater comprises of two pontoons rigidly connected together and each of the pontoons having a row of cylinders attached beneath, for improved performance characteristics. The laboratory tests were conducted in both regular and random wave flumes to study the dynamic behavior of the breakwater. Transmission and reflection coefficients, water surface elevations and velocities inside the cage like area provided in between the pontoons, rigid body motions floating breakwater and mooring forces were studied under regular and random waves and under the regular waves followed by a uniform current. The results proved the suitability of the floating breakwater to the field conditions even for large wave periods. In addition the variations in water particle kinematics, rigid body motion and mooring forces show nominal magnitudes when compared to the existing systems indicating the rigidness of the breakwater.
8
Ridlwan, Asfarur, Haryo Dwito Armono, Shade Rahmawati, and Tuswan Tuswan. "Transmission Coefficient Analysis of Notched Shape Floating Breakwater Using Volume of Fluid Method: A Numerical Study." Kapal: Jurnal Ilmu Pengetahuan dan Teknologi Kelautan 18, no. 1 (February 3, 2021): 41–50. http://dx.doi.org/10.14710/kapal.v18i1.34964.
Full textAbstract:
As one of the coastal structures, breakwaters are built to protect the coastal area against waves. The current application of breakwaters is usually conventional breakwaters, such as the rubble mound type. Climate change, which causes tidal variations, sea level height, and unsuitable soil conditions that cause large structural loads, can be solved more economically by employing floating breakwater. In this study, numerical simulations will be conducted by exploring the optimum floating breakwater notched shapes from the Christensen experiment. The comparison of three proposed floating breakwater models, such as square notch (SQ), circular notch (CN), and triangular notch (VN), is compared with standard pontoon (RG) to optimize the transmission coefficient value is analyzed. Numerical simulations are conducted using Computational Fluid Dynamics (CFD) based on the VOF method with Flow 3D Software. Compared to the experimental study, the RG model's validation shows a good result with an error rate of 8.5%. The comparative results of the floating breakwater models are found that the smaller the transmission coefficient value, the more optimal the model. The SQ structure has the smallest transmission coefficient of 0.6248. It can be summarized that the SQ model is the most optimal floating breakwater structure.
9
Suyama, H., T. Uda, and T. Yoshimura. "BEACH CHANGE AROUND DETACHED BREAKWATERS DUE TO ARTIFICIAL NOURISHMENT OF BYPASSED SAND." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 115. http://dx.doi.org/10.9753/icce.v20.115.
Full textAbstract:
Field experiment of sand bypassing was conducted on the Shimoni—ikawa Coast in Toyama Bay. The materials of 5900 m3 dredged on the updrift coast of the harbor were thrown into behind the detached breakwater. After the nourishment detailed surveys of the bottom topography around the breakwaters, wave observations and tracer tests using colored concrete blocks were carried out in order to investigate the movement of the nourished sand. Temporal and spatial changes of the shoreline positions and the sectional area of the beach in the shoreward zone of the detached breakwater are examined. It is found through the field experiment that the materials nourished behind the detached breakwater were carried slowly in the longshore direction by the westward littoral drift, dominating on the coast, without the outflow of sand through the openings of the breakwaters. It is concluded that the detached breakwater is useful to control the on—offshore sand movement and to retain the sand behind the detached breakwater.
10
Sutikno, Sigit, Fajri Almanna, Rinaldi, Mubarak, and Keisuke Murakami. "Physical and Numerical Simulation of Wave Transmission Over Submerged Breakwater." Journal of Physics: Conference Series 2049, no. 1 (October 1, 2021): 012063. http://dx.doi.org/10.1088/1742-6596/2049/1/012063.
Full textAbstract:
Abstract Nowadays, the submerged breakwaters are becoming attractive to the coastal engineer because they have many advantages including keeping aesthetic value of coastal scenery and reasonable for wave energy reduction. However, on the other hand, their design is very complicated. So, it is very important to understand the characteristics and the impact of wave because of the submerged breakwaters. For this purpose, we developed both numerical and physical model for simulation of wave over submerged breakwaters. The numerical model was developed using CADMAS-SURF, which is widely used in a practice of business in Japan. Physical model studies were performed at the Coastal Engineering Research Laboratory, University of Miyazaki, Japan to assess the performance of submerged breakwaters under a wide range of design conditions. The tests include the use of single and double submerged breakwater, as well as the impact of interval between the breakwaters which will be useful references for submerged breakwater designing in the future. The results show that the transmission coefficients of the numerical simulation have a good agreement with the experiment result with the RMS error 0.14 and 0.19 for the single and double breakwater respectively. This study found that, the application of double breakwaters has no significant impact for reducing wave energy compared to the single breakwater for the wave steepness higher than 0.007 and 0.012 based on laboratory and numerical simulation respectively. The best relative breakwater spacings are 0.75, 0.4, 0.45 and 0.35 for any kind of wave with the period of 0.6, 0.8, 1.0 and 1.2 respectively. In those conditions, the transmission coefficients are on minimum value for each kind of wave, that means the double breakwaters have the good performance on energy reduction.
11
Uda, Takaaki. "STATISTICAL ANALYSIS OF DETACHED BREAKWATERS IN JAPAN." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 150. http://dx.doi.org/10.9753/icce.v21.150.
Full textAbstract:
Construction of detached breakwaters is one of the main countermeasures against beach erosion in Japan. The number of breakwaters has been rapidly increasing, with about 2500 constructed as of the end of 1981. This study aims at the investigation of the effect and stability of detached breakwaters along Japan's coasts on the basis of survey of 1552 breakwaters constructed by the Ministry of Construction. The existing conditions of the dimensions of the detached breakwaters are statistically analyzed; the optimal dimensions for sand deposition behind a breakwater are proposed, and the critical conditions for advance of the shoreline facing an opening of breakwaters are investigated. Furthermore, the relations between the scattering rate of concrete blocks and various conditions such as bottom slope, the depth at the breakwater, the offshore distance of the breakwater and the weight of the blocks are studied. It is concluded that, in order to prevent scattering, the weight of the blocks should be at least 1.5 times heavier than that calculated from the Hudson formula.
12
Ghadimi, Parviz, Mehdi Pourmostafa, and Saeed Najafi. "Investigating the Response Amplitude Operator of a Heaving Pontoon under the Influence of a Submerged Trapezoidal Breakwater." Advances in Civil Engineering 2020 (November 5, 2020): 1–12. http://dx.doi.org/10.1155/2020/8813096.
Full textAbstract:
Although breakwaters are of great importance to damp the wave energy and protect floating vessels/facilities, they are not fully successful in reducing the waves’ height. Therefore, special attention should be paid to accurately investigate the performance of breakwaters. In this paper, the efficiency of a submerged trapezoidal breakwater in the vicinity of a floating pontoon is numerically investigated. First, different simulations are conducted to calibrate the numerical model to achieve an optimum mesh size. Next, a test case is presented for simulation of regular waves passing over a submerged breakwater. Subsequently, the heave response amplitude operator (RAO) of a rectangular pontoon facing an incoming regular wave is studied. A comparison of the obtained results in both test cases with experimental data shows good compliance. Ultimately, the heave motion of a rectangular pontoon behind four different submerged trapezoidal breakwaters facing a regular wave is investigated and different parametric studies are conducted to assess the geometrical effect of the breakwaters. This is the main novelty of the present work which studies the effect of a breakwater on the response amplitude operator (RAO) of a floating structure. In fact, a new version of RAO is presented which includes both incident and transferred wave (which pass over the breakwater) affecting the floating body. Based on the acquired results, the modified RAO of the heaving pontoon shows that breakwater has no effect on the responding frequency, but it does reduce the amplitude of the exciting wave up to 30%.
13
Pereira, Eric Joseph, Hee Min Teh, Lachmi Sri Manoharan, and Chai Heng Lim. "Design Optimization of a Porous Box-Type Breakwater Subjected to Regular Waves." MATEC Web of Conferences 203 (2018): 01018. http://dx.doi.org/10.1051/matecconf/201820301018.
Full textAbstract:
Breakwaters are used to suppress the energy of waves for providing shelter to coastal and offshore facilities. Very often, the conventional rubble mound breakwaters result in high construction cost and several environmental problems, such as water contamination and wave amplification in front of the structures due to severe wave reflection. One way to alleviate the above-mentioned problem is to appropriately increase the porosity of the breakwaters. This paper aims at developing the optimum design of a porous box-type breakwater comprising multiple scrapped pipelines via physical modelling approach. Herein, the best geometrical design of the breakwater under the governing factors of porosity, width and internal tube length is proposed. A series of experiments have been conducted under the influence of regular wave environment through the analysis of wave transmission, reflection and energy loss. Several geometrical design criteria were derived to maximize the hydraulic performance of the breakwater, when adopted at sites. The proposed breakwater is a reasonably good wave attenuator and anti-reflection structure as well as an effective energy dissipator.
14
Banijamali, Babak, and Morteza Banijamali. "BASIC DESIGN OF THE PARS PETROCHEMICAL PORT BREAKWATERS WITHIN A REGION OF DEEP WATER AND HIGH SEISMIC ACTIVITY." Coastal Engineering Proceedings 1, no. 32 (January 30, 2011): 36. http://dx.doi.org/10.9753/icce.v32.structures.36.
Full textAbstract:
This article addresses certain notable breakwater design aspects for the rare case of the Pars Petrochemical Port, where fairly slender rubble-mound breakwaters are located in water depths exceeding 32 meters within a seismically active zone. Due to the cryogenic cargo pipe-racks being placed atop breakwater crests, the design process has had to be concerned with seismic risks where the stability and deformations of breakwaters during earthquakes are important enough to govern the overall design as well as the more conventional hydraulic and geotechnical considerations. Moreover, some construction related issues pertinent to this fast-track project and the use of dredged material in the breakwater core are also discussed.
15
Mansouri, Afshin, and Babak Aminnejad. "Interaction of Submerged Breakwater by a Solitary Wave Using WC-SPH Method." Modelling and Simulation in Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/524824.
Full textAbstract:
Interaction of a solitary wave and submerged breakwater is studied in a meshless, Lagrangian approach. For this purpose, a two-dimensional smoothed particle hydrodynamics (SPH) code is developed. Furthermore, an extensive set of simulations is conducted. In the first step, the generated solitary wave is validated. Subsequently, the interaction of solitary wave and submerged breakwater is investigated thoroughly. Results of the interaction of solitary wave and a submerged breakwater are also shown to be in good agreement with published experimental studies. Afterwards, the effects of the inclination and length of breakwater as well as distance between two breakwaters are evaluated on damping ratio of breakwater.
16
An, Lim Jun, and Mohammed Abdul Hannan. "Design of Breakwaters to Minimize Greenwater Loading on Bow Structures of Fixed Vessels." Fluids 6, no. 6 (June 8, 2021): 212. http://dx.doi.org/10.3390/fluids6060212.
Full textAbstract:
Greenwater (splashing of water on the deck) loading is a classical problem faced by designers of ship-shaped vessels, which becomes even worse when the vessel operates in harsh weather conditions for an extended period of time. Installation of breakwaters on the deck can play a crucial role in minimizing this impact. However, research on the design and optimization of the breakwater is still in its infancy, and this study aims at shedding further light on this area by proposing and analysing the effectiveness of three breakwater designs on a fixed box-shaped vessel. The commercial CFD software ANSYS Fluent is used for this investigation. The design model (without breakwater) was validated at first against experimental results of greenwater splashing, before performing the actual simulations with the proposed breakwater design. A vertical plate is used as the deck structure, and the greenwater pressure at several locations on that plate is measured to compare the effectiveness of various breakwater designs. Overall, breakwaters with openings (perforations, grillages, etc.) were found to be more effective in minimizing the pressure generated by the greenwater. Nevertheless, there is significant room for improvement on breakwater designs, and some topics for further research are also suggested in this regard.
17
Blackmar, Philip, and Ronald McPherson. "BATTLING THE BERING SEA: ST GEORGE ISLAND’S BERM BREAKWATER." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 20. http://dx.doi.org/10.9753/icce.v36.papers.20.
Full textAbstract:
St. George Island, Alaska is located in the Bering Sea more than 320 kilometers (200 miles) north of the nearest Aleutian Island. During original design and construction of the fishing harbor at St. George Island in the early 1980’s, stone large enough for a conventional breakwater was not available to quarry on the island, so the project utilized a berm breakwater approach with the available local stone. The long-term performance and service life of the berm breakwaters is reviewed in this paper. Construction of the berm breakwater was completed in 1987 and the breakwaters remained functional for nearly 20 years with little maintenance. In the winter of 2015/2016, approaching 30 years since initial construction, significant damage occurred during a winter storm. Repairs utilized a berm breakwater approach similar to the original design. Repairs were completed in 2 phases due to the short construction seasons at the project site.
18
Alshaikhili, Hasan Ibrahim, and Saleh Issa Khassaf. "Statistical Equation for Coefficient of Transmission over Stepped Mound Breakwater." ECS Transactions 107, no. 1 (April 24, 2022): 16859–66. http://dx.doi.org/10.1149/10701.16859ecst.
Full textAbstract:
Breakwaters are considered to be one of the most hydraulic constructions in history. The waves hit the stones that created the breakwater initially, and when they are eroded and distributed in the sea, the enhancement arrives to make a breakwater with an equilibrium shape by filling the spaces with additional stones. Although various types of breakwaters were created to defend the shoreline from rock fill or blocks, stepped mound breakwaters were implemented in this work to absorb sea wave energy by proposing a novel equation to estimate the transmission coefficient based on dimensional group following Buckingham theory.Results show that the depth of water, height of incidence wave,height of transmission wave, length of wave, step width, step height, number of steps, and inclination angle of breakwater are employed by MNLR as statistical approach to produce a nonlinear equation with R2 reach to 82%, then this equation validated with R2equal to 81%.
19
Gomes, Ana, José L. S. Pinho, Tiago Valente, José S. Antunes do Carmo, and Arkal V. Hegde. "Performance Assessment of a Semi-Circular Breakwater through CFD Modelling." Journal of Marine Science and Engineering 8, no. 3 (March 23, 2020): 226. http://dx.doi.org/10.3390/jmse8030226.
Full textAbstract:
Coastal defence works, such as breakwaters, are structures that aim to support the action of waves and dissipate their energy. Therefore, they provide conditions for stabilizing the coast, protecting ports, beaches and other coastal infrastructures and ecosystems. Semicircular breakwaters have been applied in different locations around the world due to their aesthetic advantages and high structural performance. Marine structures are subject to hydrodynamic actions normally estimated through physical models. However, these models are complex to implement, involving high costs and long experimental procedures. Thus, alternative methodologies for studying the hydrodynamic performance of these structures are of great use. This work presents the results of the application of a computational fluid dynamics (CFD) tool to study the stability of a perforated semicircular breakwater, based on a rubble mound foundation. The model was validated against experimental results of the critical weight necessary to resist sliding, taking into account the effects of water depth and different characteristics of the waves. A comparison is made between the perforated and the non-perforated solution in terms of the breakwater’s performance to dissipate wave energy. Dissipation conditions of this energy, in the exposed face, are also evaluated in detail, in order to assess the potential of this structure as a biological refuge for marine species. Both solutions show similar performance in terms of results obtained for the wave reflectivity coefficient. The turbulence dissipation on the exposed face of the perforated breakwater is limited to a region of restricted extension around it, which is advantageous in terms of the passage of species into the breakwater.
20
Sakhaee, Farhad. "Wave Runup for Nowshahr Breakwater at Tide and EBB Scenarios." Brilliant Engineering 2, no. 4 (July 4, 2021): 10–14. http://dx.doi.org/10.36937/ben.2021.004.003.
Full textAbstract:
This study investigates runup design at breakwaters and design criteria under tidal and ebb scenarios for both head and truck of Nowshahr breakwater. First part includes runup height calculations based on shore protection manuals. Based of wave height, frequency, and water depth at the toe runup height has been calculated and Second portion has been dedicated to design of head and truck of Nowshahr port based on Hudson stability formula. Collision of wave and the breakwater head, results in immediate reduction in wave energy. As wave energy propagated gradually decreases when it meets the trunk. The results showed that in both conditions weight of head would be higher than the trunk of breakwater. while, both head and trunk are designed based on high strength materials, but the head has higher degree of importance in terms of design criteria. Hudson formula is responsible for the stability of breakwater structure. Tidal case which considers a non-breaking wave as well as ebb scenario including a breaking wave has been studied to include two extreme conditions occurs to breakwaters. The results showed the higher weight of head is responsible for stability of breakwater at both conditions.
21
Ryu, Kyong Ho, Weon Mu Jeong, Jung-Eun Oh, Won-Dae Baek, and Yeon S. Chang. "Wave Height Reduction Inside Pohang New Port, Korea, Due to the Construction of a Detached Breakwater." Journal of Marine Science and Engineering 10, no. 10 (October 19, 2022): 1537. http://dx.doi.org/10.3390/jmse10101537.
Full textAbstract:
The effect of a detached breakwater, which was constructed to improve harbor tranquility inside Pohang New Port, was examined through the comparison of wave data measured before and after the construction of the breakwater. The observation data showed that the wave energy was effectively reduced by the breakwater, although the wave height measured outside the breakwater was higher after its construction. The wave energy was reduced in all of the measured wave-propagating directions, but it was also observed that the breakwater became less effective in protecting against northeastwaves than in protecting against NNE waves. The BOUSS-2D Boussinesq-type wave model was employed to analyze the pattern of wave propagation, showing that, before the breakwater’s construction, NE waves could directly enter the port, increasing the wave energy inside the port. After the breakwater’s construction, simulations showed that the detached breakwater effectively blocked the waves approaching the port from both the NNE and NE directions, although the wave heights of the waves from the extreme NE direction inside the port increased. Considering that the estimated probability of failing to preserve the port tranquility was only 0.2–0.5% for these extreme NE waves, it was concluded that no secondary structures were necessary, and the existing breakwater was sufficient for the protection of the port.
22
Murakami, Hitoshi, Yoshihiko Hosoi, and Yoshitaka Goda. "ANALYSIS OF PERMEABLE BREAKWATERS." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 155. http://dx.doi.org/10.9753/icce.v20.155.
Full textAbstract:
This paper discusses the characteristics of hydraulic and water exchange due to the wave action against vertical slit-type breakwaters. The theoretical solution of the reflection and the transmission coefficients for the breakwater models is compared with the experimental results. Furthermore, the water exchange discharge and the water concentration change through the gap of the permeable breakwater are examined experimentally. Finally the most effective geometry of the cross section is suggested for the breakwaters used here.
23
Kamath, Arun, Athul Sasikumar, and Hans Bihs. "NUMERICAL STUDY OF WAVE INTERACTION WITH A SUBMERGED POROUS BREAKWATER IN COMBINATION WITH A FLOATING BREAKWATER." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 38. http://dx.doi.org/10.9753/icce.v36.waves.38.
Full textAbstract:
Conventional emerged rubble mound breakwaters are commonly built to protect ports and marinas from direct wave action. With increased high-valued developments in the coastal region, engineers have to design innovative coastal protection structures that can provide adequate harbor tranquility with minimum visual impact. One such solution is the combination of a submerged breakwater with a floating breakwater. In this paper, the open-source CFD model REEF3D (Bihs et al. 2016) is used to simulate wave interaction with a submerged porous breakwater with a floating breakwater on the lee side. The wave interaction with the submerged porous breakwater is validated by comparison with experimental data from Hieu and Tanimoto (2006). The validated model is then used to simulate the wave interaction with a combination of the submerged breakwater and the floating breakwater. The transmission coefficient across the combination is calculated to be about 12.5%, demonstrating the possibility to provide harbor tranquility with minimum visual impact.
24
Guo, Jianting, Yongbin Zhang, Xiangqian Bian, and Sheng Xu. "Hydrodynamic Performance of a Multi-Module Three-Cylinder Floating Breakwater System under the Influence of Reefs: A 3D Experimental Study." Journal of Marine Science and Engineering 9, no. 12 (December 2, 2021): 1364. http://dx.doi.org/10.3390/jmse9121364.
Full textAbstract:
As the technical and theoretical research of floating breakwaters is becoming increasingly mature, the floating breakwaters are now being utilized, especially in offshore reefs. Therefore, it is of practical significance to study the hydrodynamic performance of a multi-module floating breakwater system under the influence of reefs. In this study, a 3D model experiment was carried out on a system consisting of eight three-cylinder floating breakwater modules under the influence of reefs. A wave attenuation mesh cage was incorporated at the bottom of the model. The floating breakwater system was slack-moored in its equilibrium position, and each module was connected by elastic connectors. The reefs were modeled on a bathymetric map of existing reefs in the East China Sea. In this experiment, the wave transmission coefficients, motion responses, and mooring forces of the floating breakwater system were measured. The results showed that the three-cylinder floating breakwater in the beam waves (β = 90°) has excellent wave attenuating performance under the influence of reefs, especially for short-period waves. However, under the influence of the reef reflection wave and the shallow water effect, the motion responses in the three main stress directions of the floating breakwater were large, and there was some surge and pitch motion. Under the influence of the aggregation and superposition of reflected waves on both sides of the reefs, the peak mooring forces in the middle position of the floating breakwater system were the largest at large wave height. The three-cylinder floating breakwater exhibited satisfactory hydrodynamic performance under the influence of reefs. It has broad application prospects in offshore reefs.
25
Song, Sunghoon, Minsu Park, Youngjun You, Younju Jeong, and Yoonkoog Hwang. "NUMERICAL ANALYSIS OF INTERLOCKING CAISSON BREAKWATER USING MODULAR SYSTEM." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 20. http://dx.doi.org/10.9753/icce.v36.structures.20.
Full textAbstract:
Breakwaters have been severely damaged quite often since they are directly exposed to large waves. And damage level of breakwaters has been scaled up because of abnormal global climate changes. In particular, according to the report of caisson breakwater damages in Japan(Takayama, 2002), it was found that damages caused by caisson sliding, account for more than 70% of breakwater failure modes. So, the design criteria for new breakwaters is being intensified to cope with abnormal global climate changes and unusual waves. In the case of a long structure, the wave force is reduced due to the phase difference in oblique waves. Therefore, if a caisson is made as long as possible, the stability of breakwaters could be ensured even if unusual high waves occur. Recently, interlocking caisson systems, which are to form a long caisson by interlocking individual caissons with each other, have been much attention to enhance the structural stability of conventional caisson breakwaters. In the present study, a modular caisson was proposed that can improve structural stability and workability by using the shear-key interlocking system; and the wave force reduction effects of the modular caisson breakwater were evaluated by numerical analysis method.
26
MacIntosh, K. J., and W. F. Baird. "PROTOTYPE EXPERIENCE WITH RUBBLE MOUND BREAKWATERS." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 153. http://dx.doi.org/10.9753/icce.v20.153.
Full textAbstract:
At the 19th ICE Conference in Houston in 1984 an alternative concept for the design of rubble mound breakwaters was introduced. This concept has the objective of providing a least cost structure by optimizing the use of locally available materials and utilizing simple construction procedures. Contractors' bids demonstrated that significant cost savings could be achieved, when compared to the cost of traditional designs. Considerable prototype experience has now been obtained with this concept of breakwaters. Breakwaters have been built using the concept in Canada, the United States, and Iceland since 1984 and have been subjected to storms and ice action. Prototype observations have supported the performance predicted during the design process. In this paper surveys of a breakwater taken after construction and after storm action are presented. In addition to wave action, this breakwater has also been subjected to extensive ice action. The response of the breakwater has been monitored and observed and is discussed.
27
Nakamura, Takayuki, and Tohru Kouno. "PRACTICAL APPLICATION OF A JACKET-TYPE BREAKWATER." Coastal Engineering Proceedings 1, no. 32 (February 2, 2011): 54. http://dx.doi.org/10.9753/icce.v32.structures.54.
Full textAbstract:
In this study, a new jacket-type breakwater was proposed for the economical construction of breakwaters in deep-sea ports. This breakwater consists of water chambers with two inclined walls and a submerged horizontal plate. In order to reinforce the breakwater structure, the inclined support piles were adopted instead of vertical piles. Accordingly, the inclined walls were used as front and rear curtain walls. Piston mode wave resonance can be employed in the water chamber to effectively dissipate incoming waves by the generation of separated flows and the resultant vortex flows around the front curtain wall. The performance of the proposed breakwater was examined from the theoretical and experimental viewpoints. Considering the experimental results, we decided to construct an economical water-chamber-type breakwater on the adopted site.
28
Naiborhu, Maria Angelin, Yani Nurita Purnawanti, and Silvia Dewi Kumalasari. "Desain dan Konstruksi Pemecah Gelombang dengan Sisi Miring." Jurnal Teknik Transportasi 1, no. 2 (December 16, 2020): 106. http://dx.doi.org/10.54324/jtt.v1i2.537.
Full textAbstract:
Sloping breakwater is the type of breakwater requires large volume of rock and protection armor. Material increase during construction is often occur due to several factors. The main influenced factor is wave condition during construction. The main purpose of this research is to investigate the increasement of the materials due to breakwater profile changes caused by wave action during construction stage based on literature study of real construction data of breakwater construction at one of the thermal power plant in South Java Sea. This research is expected to provide an overview for designers to determine the cross-profile of a breakwater which is constructible and select the appropriate construction method to reduce the risk of excessive material increase during construction, especially for breakwaters located in deep and rough sea.
29
'Izzat Na'im, Ibrahim, Ab Razak Mohd Shahrizal, and Mat Desa Safari. "A Short Review of Submerged Breakwaters." MATEC Web of Conferences 203 (2018): 01005. http://dx.doi.org/10.1051/matecconf/201820301005.
Full textAbstract:
Breakwaters are used around the globe as a mean of protection against beach erosion by reducing the height of incoming waves into smaller transmitted waves. In addition, breakwaters can efficiently be used to preserve tranquillity inside the harbour basin, to decrease the deposition of sediments that can lead to water pollution at the harbour entrances, and to be a sanctuary for marine habitats. The purpose of this study is to discuss the application of the innovative submerged breakwater globally and in Malaysia. In addition, the comparison between submerged and emerged breakwater are briefly explained to understand the distinction between these two structures. The future experiment of the newly developed breakwater in Malaysia known as WABCORE is also included in this paper where the experimental setup and expected results are discussed.
30
Sharif Ahmadian, Amir, and Richard Simons. "3-D WAVE FIELD AROUND SUBMERGED BREAKWATER." Coastal Engineering Proceedings 1, no. 33 (December 15, 2012): 13. http://dx.doi.org/10.9753/icce.v33.structures.13.
Full textAbstract:
Methods for designing submerged breakwaters are still being developed, particularly in respect of the 3D nature of wave-breakwater interaction. Many of the available design tools are inefficient as they are not able to provide any information on the spatial distribution of the wave field around breakwaters, and cannot therefore guarantee reliability and accuracy for the engineer. There is thus a need for an engineering design tool with the ability to model spatial variation of wave height. This paper proposes a method based on machine learning algorithms for predicting the nearshore wave field behind a submerged breakwater that includes both 2D and 3D effects. The proposed numerical model has been validated by various scales of laboratory data. Comparisons reveal the ability of the proposed model to predict the wave field around submerged breakwater.
31
Kohno, H., T. Uda, and Y. Yabusaki. "ON THE SCATTERING OF CONCRETE ARMOUR UNITS OF DETACHED BREAKWATERS DUE TO WAVES." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 145. http://dx.doi.org/10.9753/icce.v20.145.
Full textAbstract:
On the Fuji Coast 15 detached breakwaters and 17 wave dissipating breakwaters have been constructed to prevent beach erosion. By virtue of the construction of the breakwaters the retreat rate of the shoreline position has decreased. However a large number of concrete blocks have been scattered due to waves. This study investigates the actual circumstances on the scattering of the concrete armour units of the detached breakwaters through the field observations on the Fuji Coast located in Suruga Bay facing the Pacific Ocean. The change rate of the plane area of the breakwater is examined from the aerial photographs, and the relationships among the parameter, the depth at the offshore foot of the breakwater and the number of the removed concrete armour units are investigated.
32
Isaacson, Michael, and Ronald Byres. "FLOATING BREAKWATER RESPONSE TO WAVE ACTION." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 162. http://dx.doi.org/10.9753/icce.v21.162.
Full textAbstract:
The present paper describes a study carried out to investigate floating breakwater behavior in waves. Components of the study include a field survey of floating breakwaters in British Columbia, Canada, the development of a numerical model of breakwater behavior and the experimental testing of a particular breakwater design. The numerical model has been developed to provide breakwater motions, transmission coefficients and mooring forces. The model combines linear diffraction theory for obliquely incident waves, a mooring analysis, the inclusion of viscous damping coefficients obtained from experimental or field data, and the inclusion of drag and wave drift forces for use in the static analysis of the moorings. The experiments were carried out with normally incident regular waves of different heights and periods. Preliminary results indicate that the numerical model should prove to be a useful tool in floating breakwater design.
33
Teh, Hee Min. "Wave Transmission over the Low-Crested Sand Container Breakwaters." Applied Mechanics and Materials 802 (October 2015): 57–62. http://dx.doi.org/10.4028/www.scientific.net/amm.802.57.
Full textAbstract:
Breakwaters made of sand container is one of the most economical options for wave protection at coastal areas. These breakwaters have been adopted with mixed success at several locations in Malaysia. Nevertheless, the performance of these structure has not been properly studied and documented to date. This study is undertaken to study the wave transmission ability of the submerged sand container breakwater with respect to its width and height as well as the water depth. A number of experiments have been conducted in a wave flume to quantify the wave transmission coefficient of the test models of different layouts when exposed to regular waves. The experimental result has shown that the breakwater is effective in arresting the shorter period waves, particularly in shallow water. The height of the breakwater has to be increased in order to arrest the longer period waves.
34
Verhaeghe, Hadewych, Luc Van Damme, Jan Goemaere, Evy Boone, and Julien De Rouck. "SETTLEMENT MEASUREMENTS OPTIMISING CONSTRUCTION OF A BREAKWATER ON SOFT SOIL." Coastal Engineering Proceedings 1, no. 33 (December 28, 2012): 87. http://dx.doi.org/10.9753/icce.v33.structures.87.
Full textAbstract:
The need of an improved harbour access resulted into the construction of two new rubble mound breakwaters in Ostend, Belgium (Verhaeghe et al., 2010). Extensive soil investigation during the design phase of the breakwaters showed that the most northern part of the western breakwater is located in a zone containing a thick upper layer of soft material. To deal with the bad soil characteristics, a very strong geotextile was used to serve as a kind of armouring of the breakwater. An extensive analysis was carried out to determine how fast construction could go on, avoiding overall geotechnical failing, and to determine the settlements to be expected. During construction of the western breakwater, extensive settlement measurements were performed. This paper describes the settlement calculations performed with Plaxis2D versus the settlement measurements performed on site, leading to an optimised phasing of the construction works.
35
Hall, Kevin R. "Numerical solutions to wave interaction with rubblemound breakwaters." Canadian Journal of Civil Engineering 17, no. 2 (April 1, 1990): 252–61. http://dx.doi.org/10.1139/l90-031.
Full textAbstract:
The interaction of a wave with a rubblemound breakwater results in a complex flow field which is both nonlinear and turbulent, particularly within a region close to the surface of the structure. Numerical models describing internal flow in a rubblemound breakwater are becoming increasingly important, particularly as the influence of scale effects on internal flow in physical hydraulic models are becoming understood as important. A number of numerical models to predict the internal breakwater flow kinematics have been produced in the past two decades. This paper provides a review of the state-of-the-art of numerical modelling of wave interaction with rubblemound breakwaters. Details of the theoretical development and the resulting numerical solution techniques are presented. Methods for incorporating secondary effects such as two-phase (air–water) flow, inertia, and unbalanced boundary conditions are discussed. Limitations of the models resulting from the validity of the assumptions made in order to effect a numerical solution are discussed. Key words: breakwaters, internal flow, porous media flow, numerical modelling, rubblemound breakwaters.
36
Kaligatla, R. B., N. M. Prasad, and S. Tabssum. "Oblique interaction between water waves and a partially submerged rectangular breakwater." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 234, no. 1 (June 16, 2019): 154–69. http://dx.doi.org/10.1177/1475090219853748.
Full textAbstract:
A problem of oblique wave scattering by a rectangular breakwater floating in water of uneven depth is solved by applying matched eigenfunction expansion method. Three positions of breakwater are considered. The width and draft of breakwater are assumed to be finite, whereas its length is infinite. Breakwater is studied in the settings of without backwall and with a backwall. By using matching conditions at interface boundaries and making use of orthogonal property of eigenfunctions, the problem is converted to a system of algebraic equations. Breakwater’s position is proposed for which wave reflection, transmission, and force on wall are optimized. The breakwater with certain width and draft reflects more wave energy than the one with zero-draft. In the case of absence of wall, breakwater at lee side to the step induces least transmission of waves. In the case of presence of wall, suitable position of breakwater is suggested based on a range of wave frequency to mitigate force on wall. Optimum distances between wall and breakwater are found to attain less force on wall. Using Green’s identity, energy balance relation is derived to check accuracy in results. The findings are likely to be useful to assess the performance of a breakwater in different positions in water of uneven depth.
37
Huh, Jungwon, Nhu Son Doan, Van Ha Mac, Van Phu Dang, and Dong Hyawn Kim. "Calibration of Load and Resistance Factors for Breakwater Foundation Design. Application on Different Types of Superstructures." Journal of Korean Society of Coastal and Ocean Engineers 33, no. 6 (December 31, 2021): 287–92. http://dx.doi.org/10.9765/kscoe.2021.33.6.287.
Full textAbstract:
Load and resistance factor design is an efficient design approach that provides a system of consistent design solutions. This study aims to determine the load and resistance factors needed for the design of breakwater foundations within a probabilistic framework. In the study, four typical types of Korean breakwaters, namely, rubble mound breakwaters, vertical composite caisson breakwaters, perforated caisson breakwaters, and horizontal composite breakwaters, are investigated. The bearing capacity of breakwater foundations under wave loading conditions is thoroughly examined. Two levels of the target reliability index (RI) of 2.5 and 3.0 are selected to implement the load and resistance factors calibration using Monte Carlo simulations with 100,000 cycles. The normalized resistance factors are found to be lower for the higher target RI as expected. Their ranges are from 0.668 to 0.687 for the target RI of 2.5 and from 0.576 to 0.634 for the target RI of 3.0.
38
Nguyen, Huu Phu, Jeong Cheol Park, Mengmeng Han, Chien Ming Wang, Nagi Abdussamie, Irene Penesis, and Damon Howe. "Representative Transmission Coefficient for Evaluating the Wave Attenuation Performance of 3D Floating Breakwaters in Regular and Irregular Waves." Journal of Marine Science and Engineering 9, no. 4 (April 6, 2021): 388. http://dx.doi.org/10.3390/jmse9040388.
Full textAbstract:
Wave attenuation performance is the prime consideration when designing any floating breakwater. For a 2D hydrodynamic analysis of a floating breakwater, the wave attenuation performance is evaluated by the transmission coefficient, which is defined as the ratio between the transmitted wave height and the incident wave height. For a 3D breakwater, some researchers still adopted this evaluation approach with the transmitted wave height taken at a surface point, while others used the mean transmission coefficient within a surface area. This paper aims to first examine the rationality of these two evaluation approaches via verified numerical simulations of 3D heave-only floating breakwaters in regular and irregular waves. A new index—a representative transmission coefficient—is then presented for one to easily compare the wave attenuation performances of different 3D floating breakwater designs.
39
Teh, Hee Min, Vengatesan Venugopal, and Tom Bruce. "PERFORMANCE ANALYSIS OF COMPOSITE SEMICIRCULAR BREAKWATERS OF DIFFERENT CONFIGURATIONS AND POROSITIES." Coastal Engineering Proceedings 1, no. 33 (October 25, 2012): 38. http://dx.doi.org/10.9753/icce.v33.structures.38.
Full textAbstract:
The perforated free surface semicircular breakwater developed by Teh et al. (2010) was experimentally proven to be an effective anti-reflection structure with high energy dissipation ability. However, the performance characteristics of the breakwater deteriorated with a decrease in the immersion depth and an increase in wavelength. To enhance the performance of the breakwater with limited immersion depth, wave screens of different configurations and porosities were introduced below the free surface semicircular caisson. The hydrodynamic characteristics of these composite breakwaters were investigated in irregular waves using physical modelling. Comparisons of the experimental results showed that the semicircular caisson with a double screen of 25% porosity was a better breakwater configuration compared to that with a single screen. The extension of wave screen was also found to be particularly helpful in attenuating longer waves.
40
Vona, Iacopo, Matthew Gray, and William Nardin. "The Impact of Submerged Breakwaters on Sediment Distribution along Marsh Boundaries." Water 12, no. 4 (April 2, 2020): 1016. http://dx.doi.org/10.3390/w12041016.
Full textAbstract:
Human encroachment and development on coastlines have led to greater amounts of armoring of shorelines. Breakwaters are a common feature along coastlines, which are used to dampen wave energy and protect shorelines from flash floods or overwash events. Although common, their effects on sediment transport and marsh geomorphology are poorly understood. To address this gap, our study quantifies the effects of breakwaters on sediment transport and marsh evolution under different wave regimes using Delft3D-SWAN, a dynamic geomorphodynamic numerical model. Model configurations used the same numerical domain, but scenarios had different sediments, waves, tides, basin slopes and breakwater distances from the shoreline to explore how waves and tidal currents shape coastal margins. Model results suggested breakwaters were responsible for an average wave damping between 10–50%, proportional to the significant wave height across all modeled scenarios. Shear stress at the beginning of the marsh and the volume of sediment deposited at the end of the simulation (into the marsh behind the breakwater) increased on average between 20–40%, proportional to the slope and distance of the breakwater from the shoreline. Sediment trapping, defined as the ratio between the volume of sediment housed into the salt marsh behind and away from the breakwater, was found to be less than 1 from most model runs. Study results indicated that breakwaters are advantageous for wave breaking to protect shorelines from the wave’s energy, however, they might also be an obstacle for sediment transport, negatively affecting nourishment processes, and, consequently, impeded long-term salt marsh survival. Identifying a balance between waves dampening and shoreline nourishment should be considered in the design and implementation of these structures.
41
Yamamoto, Masato, Kazumasa Mizumura, Taiji Endo, and Naofumi Shiraishi. "RELIABILITY BASED DESIGN OF RUBBLE-MOUND BREAKWATER." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 153. http://dx.doi.org/10.9753/icce.v21.153.
Full textAbstract:
The object of this present research is to study probabilistic design of armor blocks protecting composite breakwaters and to produce optimum design methodology for S-shaped breakwaters in terms of failure probability and construction cost. Failure probability in the vicinity of the still water level is greatest in the case of uniform sloped breakwaters. Therefore,S-shaped breakwaters of which the slope near the still water level is milder have a reduced risk of damage compared to uniform sloped ones. The optimum design index presents good economics and reliability in rubble-mound breakwater design.
42
Shahrabi, Mostafa, and Khosrow Bargi. "Structural control of the floating breakwaters by implementation of tuned liquid column damper." Advances in Structural Engineering 23, no. 8 (January 13, 2020): 1587–600. http://dx.doi.org/10.1177/1369433219898081.
Full textAbstract:
The growing maritime activities have led offshore engineers to the application of floating breakwaters to protect coastlines from erosion and to provide a layer of support to ports in the case of strong wave actions. In these applications, minimizing the floating part responses to wave-induced excitations as one of the most critical operational characteristics would be a key factor. In this article, the structural responses of the floating breakwaters are studied through modeling and simulation. To mitigate the floating part wave-induced vibrations, an attached tuned liquid column damper is integrated into the simulation. In the first stage, the numerical model of the floating breakwater system containing the floating body and the mooring system is created. Then, by proposing an iterative coupling procedure, the joint tuned liquid column damper-floating breakwater model is developed. Several rigorous study cases are defined to evaluate the effect of tuned liquid column damper on controlling the floating body unwanted vibrations. In this application, the Airy wave theory and the Joint North Sea Wave Observation Project wave spectrum are used for wave excitations. In order to evaluate the effect of tuned liquid column damper on floating breakwaters, some design parameters like floating body motions and mooring system-mobilized tensile stresses are evaluated. The simulations are conducted in both the time domain and the frequency domain for cases with and without tuned liquid column damper. The rain flow counting method is applied to perform the mooring system fatigue analysis. The study results clearly proved that implementation of tuned liquid column damper would mitigate the floating body responses compared to the original floating breakwater system. In addition, it is indicated that the fatigue-induced failure risks in tuned liquid column damper-floating breakwater mooring system is decreased that would reduce the procurement costs and increase the operational safety of the floating breakwater system.
43
Zhang, Chi, and Allan R. Magee. "Effectiveness of Floating Breakwater in Special Configurations for Protecting Nearshore Infrastructures." Journal of Marine Science and Engineering 9, no. 7 (July 20, 2021): 785. http://dx.doi.org/10.3390/jmse9070785.
Full textAbstract:
This paper investigates the effectiveness of floating breakwaters consisting of two barges (L-shape), three barges (U-shape), four barges (barge frame), and conventional single floating breakwater. The floating breakwaters of different spatial layouts have sheltered internal gaps/moonpools when compared to their conventional counterparts. The motions of these floating breakwaters and their effectiveness in wave transmission and motion reduction of the protected floating bodies are evaluated. The study is conducted based on a subsystem of a floating hydrocarbon storage facility that combines a floating breakwater with two floating tanks, studied previously. Numerical models based on linear potential flow theory are built for these floating breakwaters with and without the floating tanks. The numerical models of the barge frame are validated through laboratory experiments, and the dipole damping lids to reduce the resonant fluid motions in the gaps/moonpools are calibrated with experimental results. The L-shape floating breakwater is found effective in reducing wave transmissions without the presence of the floating tanks, while the barge frame is the most effective in the motion reduction of the floating tanks. In addition, significant fluid resonant motions are identified for all investigated floating breakwaters, including the conventional one. Orienting the structure obliquely can improve the performance of the floating breakwaters of special configurations, especially the barge frame. The results and findings show the importance of considering the protected floating structures in the analysis when designing floating breakwaters for many types of marine structures, including floating fish farms and floating cities in coastal waters.
44
Gao, Zhi Qi, Rui Jin Zhang, Shu Guang Luan, and Dong Wei Fu. "Experimental Study on Regular Wave of Transmission Coefficient through a Hollow-Block Mound Breakwater." Applied Mechanics and Materials 170-173 (May 2012): 2200–2203. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.2200.
Full textAbstract:
Besides wave attenuation, hollow-block mound breakwater acts as artificial reef which could protect the marine biology and repair the marine ecological environment. Transmission coefficient is the main index of breakwater’s wave attenuation effect evaluation. In this paper through the sectional model experiment on the special assembled hollow-block mound breakwater under regular wave, affecting factors (opening size, water depth, wave period, incident wave height) of the transmission coefficient of breakwater were studied. The main factors that influence the wave attenuation of the hollow-block mound breakwater are the opening size of the hollow-block and the depth of the water while the wave period and the wave height of the incident wave have less influence for the wave attenuation of the breakwater. The research results can provide the reference for the following theoretical research and engineering practice.
45
Sujatmoko, Bambang, Manyuk Fauzi, and Doli Ananta Putra. "Wave pattern simulation around the breakwater configuration in Bantan coast, Bengkalis." MATEC Web of Conferences 276 (2019): 04018. http://dx.doi.org/10.1051/matecconf/201927604018.
Full textAbstract:
Bantan Coast in Bengkalis Island that suffered worst abrasion due to wave attack. Protection of abrasion area against the wave can be done by proper lay-out of breakwater with certain configuration. To get the optimal configuration of breakwater, wave pattern around the breakwater were analyzed quantitatively. It was conducted to obtain the optimum condition of wave height reduction produced. Evaluation of breakwater lay-out effect to wave pattern can be done by numerical model approached. Wave pattern simulation that occurred due to the breakwater was done by Surface water Modelling System (SMS) - CGWAVE software module. This module is a 2-D depth average numerical model using finite element model. To get accurate simulation, a deviation of the numerical result and the measurement result at several locations was used as the indicator parameter in the calibration process. The results showed that from the result of calibration process was used 1.3 meters wave height and 5.4 seconds wave period. Three breakwaters 20 meters slit configuration produced a maximum value of wave height reduction and wave velocity reduction (in comparison wave simulation without breakwater). This configuration produces 60% height reduction and 14% velocity reduction.
46
Zhao, Xuanlie, Dezhi Ning, Chongwei Zhang, Yingyi Liu, and Haigui Kang. "Analytical Study on an Oscillating Buoy Wave Energy Converter Integrated into a Fixed Box-Type Breakwater." Mathematical Problems in Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/3960401.
Full textAbstract:
An oscillating buoy wave energy converter (WEC) integrated to an existing box-type breakwater is introduced in this study. The buoy is installed on the existing breakwater and designed to be much smaller than the breakwater in scale, aiming to reduce the construction cost of the WEC. The oscillating buoy works as a heave-type WEC in front of the breakwater towards the incident waves. A power take-off (PTO) system is installed on the topside of the breakwater to harvest the kinetic energy (in heave mode) of the floating buoy. The hydrodynamic performance of this system is studied analytically based on linear potential-flow theory. Effects of the geometrical parameters on the reflection and transmission coefficients and the capture width ratio (CWR) of the system are investigated. Results show that the maximum efficiency of the energy extraction can reach 80% or even higher. Compared with the isolated box-type breakwater, the reflection coefficient can be effectively decreased by using this oscillating buoy WEC, with unchanged transmission coefficient. Thus, the possibility of capturing the wave energy with the oscillating buoy WEC integrated into breakwaters is shown.
47
Kim, Kyu Han, and Bum Shick Shin. "Erosion Mitigation Using Submerged Breakwater Composed of Artificial Reefs." Applied Mechanics and Materials 744-746 (March 2015): 1171–74. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.1171.
Full textAbstract:
In this study, erosion mitigation by submerged breakwater with artificial reefs is investigated among other means of countermeasures. Beach erosion mechanism near the submerged breakwater and the performance of artificial reef blocks are analyzed in the laboratory. Two-dimensional and three-dimensional laboratory experiments are applied to the analysis. The results of two-dimensional experiments prove that new artifi-cial blocks showed a better performance than the existing blocks in terms of wave attenuation due to wave breaking turbulence near the crest of the structure. Three-dimensional experiments show reduced return flow velocity by half by installing another type of new artificial block in between submerged breakwaters. Return flow has been creating vulnerability in countermeasures by submerged breakwater. Therefore, artifi-cial reef blocks suggested by this study offer solutions to the existing mitigation problems with submerged breakwater.
48
Kim, S., and H. Lee. "Boundary element modelling of wave diffraction by interaction with wave-offshore structure and dredged region." Polish Maritime Research 17, no. 2 (January 1, 2010): 67–71. http://dx.doi.org/10.2478/v10012-010-0020-5.
Full textAbstract:
Boundary element modelling of wave diffraction by interaction with wave-offshore structure and dredged region The purpose of this study is to estimate the wave height at the front face of breakwater (Refracted breakwater and Straight breakwater), when dredging like the submarine pit is performed in the distant offshore from outer breakwater. The wave field of the problem is considered to be two dimensional planes and the configuration of the pit region is designated by a single horizontal long-rectangular system. The numerical approach uses the Green function based on the boundary integral approach. The results of the present numerical works are illustrated by applying the normal and inclined incidence. It is shown that in the case of normal incidence, the ratio of wave height reduction at the front face of both types of breakwaters is approximately more than 20% due to the effect of the submarine pit on the sea bed. Furthermore, regardless of the type of breakwater and the difference in incident wave angles, the ratio of wave height was shown to be reduced.
49
Ou, Shan-Hwei, Shiaw-Yih Tzang, and Tai-Wen Hsu. "WAVE FIELD BEHIND THE PERMEABLE DETACHED BREAKWATER." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 8. http://dx.doi.org/10.9753/icce.v21.8.
Full textAbstract:
Based on the concept of linear superposition, the model for combined wave refraction and diffraction developed by Liu et al. is extended to the situation of permeable detached breakwaters in a slowly varying water depth. Two cases are investigated which include a semi-infinite permeable breakwater and a single permeable breakwater. Laboratory results with a particular transmission coefficient in a wave basin are used to compare with the theoretical results. Fair agreements are found.
50
Agung, Ida Bagus. "PENGARUH DURASI SERANGAN GELOMBANG TERHADAP TINGKAT KERUSAKAN LAPIS LINDUNG PEMECAH GELOMBANG." Science Tech: Jurnal Ilmu Pengetahuan dan Teknologi 1, no. 1 (August 2, 2015): 18–27. http://dx.doi.org/10.30738/jst.v1i1.471.
Full textAbstract:
this research tetrapod have been utilized for breakwater cover layer or armour layer. The effect of wave duration on the armor layer tetrapod stability was studied. The models were run in the irregular wave flume, where Bretschneider spectrum may be generated attacking the breakwater. The waves were set to break before reaching the breakwater. The test was conducted until the damage level of armour layer reached more than 5 %. The result of the research showed that waves duration and the high of the wave attack affect the stability of armour layer, especially when the wave was Rayleigh distributed. The effect of waves duration reduced as more and more waves broken before reaching the structure of the breakwater