scholarly journals PHYSICAL MODEL ON WAVE DISSIPATION EFFECT OF PERFORATED CAISSON

2011 ◽  
Vol 1 (32) ◽  
pp. 20
Author(s):  
Yunpeng Jiang ◽  
Hanbao Chen ◽  
Longzai Ge
Keyword(s):  
Water Level ◽  
Physical Model ◽  
Wave Height ◽  
High Water ◽  
Physical Model Test ◽  
Wave Forces ◽  
Height Distribution ◽  
Wave Dissipation ◽  
Dissipation Effect ◽  
Perforated Caisson

Perforated caisson structure was usually adopted by harbor engineering design to reduce wave height and wave forces on the structure. Through wave physical model test, wave height distribution in front of non-perforated and perforated caisson with different directions was studied respectively with the layout of a project in China. And then dissipation effect of wave height of perforated caisson was obtained from comparison of the two cases. It was indicated from the results that reduction effect of wave height had great relation with the position of perforation on the caisson when dimension of caisson and perforation, perforation rate were fixed. The perforated caisson had a remarkable wave-dissipation effect when the perforation was between once the wave height above or below the still water level, which proved the rationality of the recommendation of Code for Design and Construction of Breakwaters. It was suggested for this project that design of perforation should be consistent with the code as possible and near the design high water level.

An Experimental Study on the Performance of Wave Dissipation of Artificial Sand Bar

2012 ◽  
Vol 226-228 ◽  
pp. 2299-2302
Author(s):  
Duo Cang Zhao ◽  
Bing Shi ◽  
Li Peng Yang ◽  
Zhi Yong Zhang
Keyword(s):  
Experimental Study ◽  
Water Level ◽  
Transmission Coefficient ◽  
Wave Height ◽  
High Water ◽  
Wave Parameter ◽  
Regular Waves ◽  
Wave Dissipation ◽  
High Water Level ◽  
Sand Bar

The paper summarizes the results of the performance of wave dissipation of an artificial sand bar experimental study under regular waves .In the experiment, the water levers are 0.00m、design high water level (1.35m) and extreme high water level (2.66m) ,it chooses the corresponding the limit wave height of three kinds of water level ,and analyzes the influences of relative height of artificial sand bar (d/H)、relative water depth of artificial sand bar (R/H) and wave steepness (H/L) on transmission coefficient of wave.The result shows that artificial sand bar has well the performance of consuming wave energy, the incident wave height starts up clearly decrease, while wave passes through artificial sand bar.With changing in conditions of artificial sand bar geometric dimensioning and wave parameter, transmission coefficient of regular waves also Changes.

Environmental Assessment of Xinhe Beach Development

2020 ◽  
Vol 980 ◽  
pp. 459-468
Author(s):  
Zhi Lin Sun ◽  
Ju Yuan Luo ◽  
Weng Ang Xiang ◽  
Yu Meng Gong
Keyword(s):  
Velocity Field ◽  
Water Level ◽  
Wave Height ◽  
Ecological Environment ◽  
Environmental Damage ◽  
Height Distribution ◽  
Astronomical Tide ◽  
Effective Wave ◽  
Hydrodynamic Environment ◽  
The Impact

The proliferation of beach renovation is affecting the change of the landform of the coast and threatening the ecological environment. Therefore, it is necessary to assess the impact on the environment after the beach is transformed. The survey area is located near the Shipu fishing port in the south of Ningbo City, Zhejiang Province. Based on the Delft-3D grid nesting model and wave-fluid coupling model, the astronomical tide and hydrodynamic environment of the 30 days before the construction were simulated. After the beach was rebuilt and sand was added and the spur dike was added, the astronomical tide and hydrodynamic environment were again simulated. Finally, based on the simulated data, the water level, velocity field, effective wave height distribution, and siltation and siltation of Xinhe Beach were obtained. Xinhe Beach's environmental damage risk indicators can be evaluated based on water level, velocity field, effective wave height direction and sediment erosion and deposition. Artificial sanding and construction of spur dikes will change the hydrodynamics and scouring and siltation of Xinhe Beach, but have little effect on the coastal terrain and ecological environment.

scholarly journals Study of a self-scouring outfall in Lake Ontario by physical and computer modeling

2021 ◽  
Author(s):  
Shanil Persaud
Keyword(s):  
Water Level ◽  
Wave Height ◽  
Lake Ontario ◽  
High Water ◽  
Wave Direction ◽  
Computational Fluid Dynamics Cfd ◽  
Run Up ◽  
Bodies Of Water ◽  
The City ◽  
Better Than

Coastal outfalls that discharge storm water and/or sewerage into bodies of water are part of a collection of critical municipal infrastructure that must be kept functioning properly at all times so as to avoid expensive frequent maintenance and environmental problems. The Green Road costal outfall pipe, located in an embayment on the shores of Lake Ontario in the City of Hamilton, is subject to sediment plugging by waves that transport sediments from an eroding bluff to the east into the study outfall pipe, thereby reducing its hydraulic discharge capacity. To alleviate the problem of outfall blockage, a 1:15 scale undistorted physical (hydraulic) model ws designed and built at the National Water Research Institute (NWRI) to study the performance of a self-scouring outfall (SSO), a structure that utilizes combination of wave run-up slopes, converging walls and steep outlet channels to promote self-cleansing with respect to sediment to prevent direct sediment intrusion into the outfall pipe. A commercial computational fluid dynamics (CFD) model FLUENT, was used to study the internal hydrodynamics of the complex outfall structure. Results from the physical model determined that the performance of the SSO is a function of wave direction, water level, wave height and period, as well as sediment characteristics. Model results indicate that a SSO built on the shores of Lake Ontario would be able to scour a greater amount of sediment in conjunction with a high water level and wave height of 75.07 m and 1.95 m, respectively. A modified SSO design reduced sedimentation on the wave run-up slopes by more than 25% and was 100% effective in preventing direct sediment intrusion. The structure performed exceptionally better than a traditional outfall in terms of sediment handling. Therefore, it is expected a municipality can save a great deal of money on cleanouts by installing a self-scouring outfall to prevent outfall plugging.

scholarly journals WAVE HEIGHT DISTRIBUTIONS IN SHALLOW WATERS

2011 ◽  
Vol 1 (32) ◽  
pp. 63 ◽  
Author(s):  
Stephan Mai ◽  
Jens Wilhelmi ◽  
Ulrich Barjenbruch
Keyword(s):  
Shallow Water ◽  
Water Level ◽  
Wave Height ◽  
Coastal Engineering ◽  
Shallow Waters ◽  
Height Distribution ◽  
Sea Waves ◽  
Ocean Engineering ◽  
Sea State ◽  
Marine Research

In shallow waters the wave height distribution significantly differs from Rayleigh distribution during extreme wind conditions. The EurOtop manual (Pullen et al. 2007) recommends the use of a composite Rayleigh-Weibull distribution proposed by Battjes and Groenendijk (2000) in order to describe the wave statistics in shallow waters. A test of this recommendation by using wave measurements with continuously operated radar level gauges at three different sites at the German North Sea coast for comparison revealed the necessity for a change in the parameterization given in the EurOtop manual. References Barjenbruch, U., S. Mai, N. Ohle, and U. Mertinatis. 2002. Monitoring Water Level, Waves and Ice with Radar Gauges, Proceedings of the Hydro 2002 Conference, DHyG, 328-337. Barjenbruch, U., and J. Wilhelmi. 2008. Application of radar gauges to measure the water level and the sea state, Proceedings of 31st International Conference on Coastal Engineering, ASCE, 687-695. Battjes, J.A., and H.W. Groenendijk. 2000. Wave height distributions on shallow foreshores, Coastal Engineering, 40, 161-182. http://dx.doi.org/10.1016/S0378-3839(00)00007-7 Burcharth, H.F., P. Frigaard, J. Uzcanga, J.M. Berenguer, B.G. Madrigal, and J. Villanueva. 1996. Design of the Ciervana breakwater, Bilbao, Advances in coastal structures and breakwaters, Thomas Telford, London, 26-43. Forristall, G. 2008. Offshore LNG terminal designs must overcome complications of shallow water, Oil & Gas Journal, 106(43). IAHR Working Group on Wave Generation and Analysis. 1989. List of Sea-State Parameters, Journal of Waterway, Port, Coastal and Ocean Engineering, 115(6), pp. 793-80 http://dx.doi.org/10.1061/(ASCE)0733-950X(1989)115:6(793) Klopman, G., and M.J.F. Stive. 1989. Extreme waves and wave loading in shallow water, Proceedings of E&P Forum Workshop: Wave and current kinematics and loading, Paris, Oct. 25-26. Longuet-Higgins, M. S. 1952. On the Statistical Distribution of the Heights of Sea Waves. Journal of Marine Research, 11(3), 245–266. Mai, S. 2008. Statistics of Waves in the Estuaries of the Rivers Ems and Weser - Measurement vs. Numerical Wave Model, Proceedings of the 7th Int. Conf. on Coastal and Port Engineering in Developing Countries COPEDEC, CD-ROM. Nelson, R.C. 1994. Depth limited design wave heights in very flat regions, Coastal Engineering, 23, 43-59. http://dx.doi.org/10.1016/0378-3839(94)90014-0 Pullen, T., N.W.H. Allsop, T. Bruce, A. Kortenhaus, H. Schüttrumpf, and J.W. van der Meer. 2007. EurOtop – Wave Overtopping of Sea Defences and Related Structures: Assessment Manual, Die Küste, 73, 193 pp. (online:

scholarly journals Model Test and Numerical Analysis on the Deformation and Stability of a Landslide Subjected to Reservoir Filling

Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Xinli Hu ◽  
Chuncan He ◽  
Chang Zhou ◽  
Chu Xu ◽  
Han Zhang ◽  
...  
Keyword(s):  
Water Level ◽  
Physical Model ◽  
Pore Water ◽  
Model Test ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Physical Model Test ◽  
Landslide Stability ◽  
Landslide Deformation ◽  
Reservoir Filling

Reservoir filling can affect the landslide stability and cause the landslide deformation within the reservoir area. In this paper, a physical model test and a series of numerical analyses were combined to investigate the landslide deformation and stability under reservoir filling. The surface deformation, deep displacement, and pore water pressure were recorded during the physical model test. In the model test, the increasing period of the pore water pressure inside the landslide is proposed to be a critical period for the landslide subjected to the reservoir filling. During this period, large landslide deformation occurred. The numerical analyses show that a greater factor of safety (FOS) appeared under a higher water level rising rate or a lower permeability coefficient during the water level rising stage when other variables are fixed, due to the domination of the reservoir buttressing effect which can increase the landslide resistance. During the reservoir maintaining stage, the reservoir water infiltrated into the landslide continuously to cause the matric suction dissipation and pore water pressure increase, which reduced the landslide shear strength and then decreased the landslide stability.

scholarly journals Experiment on Pressure Characteristics of Submerged Floating Tunnel with Different Section Types Under Wave Condition

2018 ◽  
Vol 25 (s3) ◽  
pp. 54-60 ◽  
Author(s):  
Qinxi Li ◽  
Shuping Jiang ◽  
Xiang Chen
Keyword(s):  
Wave Height ◽  
Wave Force ◽  
Physical Model Test ◽  
Wave Forces ◽  
Wave Load ◽  
Wave Condition ◽  
Circular Section ◽  
Elliptical Section ◽  
Horizontal Wave ◽  
Submerged Floating Tunnel

Abstract Submerged floating tunnel (SFT for short) is a special underwater traffic structure, and wave load is one of the main environmental loads of SFT structure. In this paper, the 1:60 physical model test of three kinds of SFT in a two-dimensional wave flume is tested. The effects of random irregular waves on the SFT structure under different wave heights and periods are discussed. The study shows that: (1) Compared with circular and polygonal sections, there are multiple local peaks in the elliptical section during the period. with the increase of wave height, the number of local peaks also increases. It suggests that the rotational moment plays an important role in the elliptical section which has a relatively small depth-width ratio. (2) The position of the maximum and minimum pressure in the three kinds of SFT sections is consistent. Their vertical wave forces are all larger than their horizontal wave forces. The increase of vertical wave force relative to horizontal wave force in polygon section is larger than that in elliptical section, and the difference in the circular section is the smallest. (3) Under the same traffic condition, the wave force of the elliptical and polygon section is smaller, but they are more sensitive to the change of wave height, and the increase is obvious. The distribution of wave force in the circular section is more uniform.

Study on the Extreme High Water Levels and Wave Heights of Different Return Periods in Laizhou Bay, China

2017 ◽  
Author(s):  
Chunyan Zhou ◽  
Jinhai Zheng ◽  
Jisheng Zhang ◽  
Xiaoying Fu
Keyword(s):  
Water Level ◽  
Wave Height ◽  
Return Period ◽  
Current Velocity ◽  
Yellow River ◽  
River Mouth ◽  
High Water ◽  
Water Levels ◽  
Laizhou Bay ◽  
Distribution Method

Based on good simulation results during storm events in 2009, MIKE21 was used to study the extreme water level, current velocity and wave height in Laizhou Bay, China. 95 extreme weather processes during 1988–2012 were simulated. For each event, coupled hydrodynamic and wave modules of MIKE21 was chosen to calculate the maximum water level and current velocity. The Gumbel distribution method, commonly used for estimating return-period values of marine hydrodynamic variables, is adopted in this study. The extreme high water level of 50-year return period in Laizhou Bay can reach 2.6–3.8 m; and that of 100-year return period can be as high as 2.8–4.6 m. The 50-year and 100-year return-period values of current velocity can reach up to about 2.8 m/s and 3.2 m/s respectively, both around the Yellow River mouth. Wave height strongly depends on water depth, water level rise, wind speed and direction. The results provide parameter reference for structure design in the Laizhou Bay.

scholarly journals Study of a self-scouring outfall in Lake Ontario by physical and computer modeling

2021 ◽  
Author(s):  
Shanil Persaud
Keyword(s):  
Water Level ◽  
Wave Height ◽  
Lake Ontario ◽  
High Water ◽  
Wave Direction ◽  
Computational Fluid Dynamics Cfd ◽  
Run Up ◽  
Bodies Of Water ◽  
The City ◽  
Better Than

Coastal outfalls that discharge storm water and/or sewerage into bodies of water are part of a collection of critical municipal infrastructure that must be kept functioning properly at all times so as to avoid expensive frequent maintenance and environmental problems. The Green Road costal outfall pipe, located in an embayment on the shores of Lake Ontario in the City of Hamilton, is subject to sediment plugging by waves that transport sediments from an eroding bluff to the east into the study outfall pipe, thereby reducing its hydraulic discharge capacity. To alleviate the problem of outfall blockage, a 1:15 scale undistorted physical (hydraulic) model ws designed and built at the National Water Research Institute (NWRI) to study the performance of a self-scouring outfall (SSO), a structure that utilizes combination of wave run-up slopes, converging walls and steep outlet channels to promote self-cleansing with respect to sediment to prevent direct sediment intrusion into the outfall pipe. A commercial computational fluid dynamics (CFD) model FLUENT, was used to study the internal hydrodynamics of the complex outfall structure. Results from the physical model determined that the performance of the SSO is a function of wave direction, water level, wave height and period, as well as sediment characteristics. Model results indicate that a SSO built on the shores of Lake Ontario would be able to scour a greater amount of sediment in conjunction with a high water level and wave height of 75.07 m and 1.95 m, respectively. A modified SSO design reduced sedimentation on the wave run-up slopes by more than 25% and was 100% effective in preventing direct sediment intrusion. The structure performed exceptionally better than a traditional outfall in terms of sediment handling. Therefore, it is expected a municipality can save a great deal of money on cleanouts by installing a self-scouring outfall to prevent outfall plugging.

Stability Prediction of Zhaoshuling Landslide by Physical Model Test

2012 ◽  
Vol 170-173 ◽  
pp. 1147-1150
Author(s):  
Hui Ming Tang ◽  
Xin Li Hu ◽  
Cheng Ren Xiong
Keyword(s):  
Rock Mass ◽  
Water Level ◽  
Physical Model ◽  
Failure Mechanism ◽  
Physical Model Test ◽  
Seismic Load ◽  
Digital Cameras ◽  
Deformation And Failure ◽  
Reservoir Impoundment ◽  
Reinforcement Measures

Physical model experiments are conducted to study the potential deformation and failure mechanism of Zhaoshuling landslide in the reservoir area of the Three Gorges project under the action of reservoir impoundment, water level fluctuation, building load and possible seismic load. Dial gauges, grid lines and digital cameras are used to monitor and record the deformations and displacements of the models. Research results indicate that the landslide will be basically stable while covered with seven-floor buildings whether the water level be at 145m or 175m, or falls abruptly from 175m to 145m. When the intensity of an earthquake is beyond certain degree, the rock mass will deforms and lose stability partly; and its stability will be worst when the water level falls from 175m to 145m, stability will be better when the level being at 145m and it will be best when the level being at 175m. It also indicate from deformation and failure mechanism revealed by the experiments that the best position of reinforcement measures is in Yanjiang Avenue, and the sliding resistance of the rock mass in the front part of the landslide can be used.

An Experimental Research on Optimization of Trajectory Bucket for Spillway Tunnel Outlet at Sanliping Hydropower Project

2011 ◽  
Vol 90-93 ◽  
pp. 2740-2745
Author(s):  
Xiao Fang Liu ◽  
Dang Wei Wang ◽  
He Qing Huang
Keyword(s):  
Energy Dissipation ◽  
Water Level ◽  
Physical Model ◽  
Experimental Research ◽  
High Water ◽  
Experimental Results ◽  
Hydropower Project ◽  
High Water Level ◽  
Scientific Foundation ◽  
Spillway Tunnel

Several optimized designs of trajectory bucket pattern for spillway tunnel outlet are compared in the experiment of Sanliping hydropower project integer physical model and the results show that energy dissipation of outflow nappe is sufficient after optimization and no scouring occur near the riverbank either at high water level or at low water level, which ensure the security of spillway structure. And these experimental results can provide a scientific foundation for the design of Sanliping project.

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