Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Korean Society of Coastal and Ocean Engineers
Journal Basic Information
Journal DOI :
Korean Society of Coastal and Ocean Engineers
Editor in Chief :
Volume & Issues
Volume 15, Issue 4 - 00 2003
Volume 15, Issue 3 - 00 2003
Volume 15, Issue 2 - 00 2003
Volume 15, Issue 1 - 00 2003
Selecting the target year
Evaluation of Safety Factors for the Soft Ground Breakwater Design
Kwon, O-Soon ; Jang, In-Sung ; Park, Woo-Sun ; Yum, Ki-Dai ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 197~206
A new type of breakwater, which can be applicable to soft ground without special treatment because of its light self weight and structural characteristic of bottom wall, has recently been developed. The objective of this study is to propose an evaluation method of safety factor for the new type of breakwater considering 3 categories of sliding, overturning, and bearing capacity. Previous method for gravity type of breakwater was modified and the proposed method was verified by comparing the safety factors with maximum lateral displacements, which were obtained from finite element analysis for various types of breakwaters and ground conditions. The results showed the newly proposed evaluation method of safety factors could reasonably be utilized.
The Characteristics of Wave Energy Variations by Impermeable Submerged Breakwater Using VOF Method in Irregular Wave Fields
Hur, Dong-Soo ; Kim, Do-Sam ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 207~213
This study is to numerically investigate the characteristics of wave energy variations propagating over impermeable submerged breakwaters with irregular waves. Two-dimensional numerical wave flume based on the VOF method was used. VOF method is the most efficient capable of simulating free surfaces including wave breaking. From the computed frequency spectrum results, wave breaking play important role in ability of the submerged breakwaters to dissipate incident wave energy. In case of occurring wave breaking, our analysis shows that wave energy moves to short wave period on one-row impermeable submerged breakwater’s lee side and is widely distributed not having peak period on two- row impermeable submerged breakwater’s lee side.
Reliability Analysis of Sloped Coastal Structures against Random Wave Overtopping
Lee, Cheol-Eung ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 214~223
A reliability analysis is straightforwardly applied to the sloped coastal structures against the random wave overtopping. A reliability function can be directly derived from a empirical formula in which may take into account many variables associated with the random wave overtopping. The probability of failure exceeded the allowable overtopping discharge can be evaluated as a function of dimensionless crest height with some reasonable statistical properties and distribution functions of each random variable. Some differences of probabilities of failure occurred from variations of the slopes of structures as well as types of armour are investigated into quantitatively. Additionally, the effects of the crest width of units placed in front of the concrete cap on the probability of failure may be analyzed. Finally, the sensitivity analyses are carried out with respect to the uncertainties of random variables. It is found that the overall characteristics similar to the known experimental results are correctly represented in this reliability analyses. Also, it should be noted that the probabilities of failure may be quantitatively obtained for several structural and hydraulic conditions, which never assess in the deterministic design method. Thus, it may be possible for determination on the crest height of sloped coastal structures to consider the probability of failure of wave overtopping, by which may be increased the efficiency of practical design.
Wave Screening Performance Using Floating and Submerged Breakwaters
Cho, Won-Chul ; Lee, Jin-Won ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 224~231
In this study, the hybrid breakwater system - a breakwater system combining the floating breakwater with the submerged breakwater - is used to improve the wave screening performance that may not be achieved by using the floating breakwater or the submerged breakwater, separately. Two-dimensional finite element method is used for numerical analysis and the wave reflection ratio and the wave transmission ratio are analyzed for the proposed case. In case of using the hybrid breakwater system, wave screening performance is more effective than in case of using the floating breakwater or the submerged breakwater, separately. It also shows an effective wave screening on the long wave period and an advanced wave screening performance with low height of the submerged breakwater.
Wave Control by an Array of N Bottom-Mounted Porous Cylinders
Cho, Il-Hyoung ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 232~241
The interaction of incident monochromatic waves with N bottom-mounted porous circular cylinders is investigated in the frame of three-dimensional linear potential theory. The fluid domain is divided into N+1 regions i.e. a single exterior region and N interior regions, and the diffraction potential in each fluid region is expressed by an eigenfunction expansion method(Williams and Li, 2000). The analytic results show that the porous structure reduces both the wave forces and the run-up wave around the cylinder. To verify the developed model, the systematic model test with a line array of porous cylinders is conducted at the wave tank (30 m×7 m×1.5 m). The analytic results are in good agreement with the experimental results within measured frequency range. It is concluded that the breakwater constructed with an array of porous circular cylinders shows the performance of an effective wave barrier together with the seawater-exchange effect and is considered to have vast potentials for the use of seawater-exchanging breakwater in the future.
Reliability Analysis of Caisson Type Quay wall Considering Phase Difference of Seismic Earth-Pressure
Kim, Dong-Hyawn ; Yoon, Gil-Lim ; Park, Woo-Sun ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 242~248
For reliability analysis of caisson type quay walls, an approach to include the phase difference between the caisson motion and the dynamic earth pressure is proposed. Present approach, which uses the phase difference parameter, may over-estimate earth pressure. But the proposed approach considers the phase angle instead of the phase difference in estimating resultant external load. Therefore, it is more reasonable than the previous one. Accordingly, calculation of probability of failure becomes more accurate. Numerical example is used to compare the two approaches.
Hydraulic Model Test for Armor Stability of Rubble-Mound Breakwaters
Lee, Jong-In ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 249~258
In this study, the stability of armor blocks of rubble-mound breakwaters is investigated based on the 2-dimensional hydraulic model test with irregular waves. Armor blocks were used the three types; rock, cube and tetrapod. And Hudson formula and van der Meer formula which are used for calculating the weight of armor blocks are considered. Hudson formula was developed from regular wave tests, while van der Meer formula was developed from irregular wave tests. The purpose of this paper is to compare and test two selected stability formulas using the experimental data.
A Study on the structures of flow and water quality in the Kitan strait
Heo, Jae-Yeong ; Kim, Han-Gu ; eiji, NakatsujiK ;
Journal of Korean Society of Coastal and Ocean Engineers, volume 15, issue 4, 2003, Pages 259~268
The damage of water quality like red tide occurs every year inspite of the total load regulation of pollutant inflows from land such as COD, phosphorus and so on around Seto inland sea in Japan. It is attributed to the increase of primary production due to eutrophication, and the rising and settling from the sediment containing nutrient salt. Furthermore, the recent research shows that nutrient salt such as nitrogen and phosphorus, flows into Kii channel from land as well as the Pacific ocean. To investigate the distribution of water quality and flow and residual current in Kitan strait, the field observations were carried out. The field data were obtained a time each season from 1999 to 2002. The results of observations and data of other research institution are used to understand the mechanism of pollution in the strait.