海雲台砂浜의 漂砂에 관한 硏究 = Study of Drift on HAEUNDAE Beach

다국어 초록 (Multilingual Abstract)

It must be a significant problem of national standpoint as well as Busan city that the area of Hae un dae beach continues to diminish since 1976. This problem seems to be caused by the transportion of littoral drifts.
Therefore, this paper intended to investigated parameters having best correlationship with the drift and be able to estimate transfer quantity in future, and besides to develop protection method to control the phenomena.
1. A primary factor of Haeun-dae seashore erosion is that the more wave steepness is, the more severe erosion is. When the value of slope is above 0.025 erosion occurs, and relatively accretion occurs when it is below 0.025.
And other factor is that is that if constructions place near the shoreline, erosion will be more sever. So in case of landfilling the front of the mouth of Chun river, erosion seems to be more severe because shortage of supply-sand was caused by position deformation of the mouth of river.
2. The range of specific gravities of sands in Heaun-dae beach is 2.56-2.69. At No.23 a great deal of soil was involved, at No.33 clam-shell, sand soil were mixed and dam-shells were mainly included at No.44
3. The materials of sea-bed were sampled at point of 50m, 100m, 300m, 400m, 500m, away from the shoreline of No.23, No33, No.44, No.55, No.65 relatively.
As a result of analysis of the specific gravities and median diameters, the specific gravities at both sides decrease according to the depth of water, and in the vicinity of the center a kind of cyclic phenomenon, which the specific gravities having the range of 2.76-2.27 increase and decrease in turns at intervals of 50m, appears. Near the center there are many clam-shell and S O₂, the component of pure sand is only 45.44%, so the specific gravities decrease to 2.27.
4. It seems that entrance and exit of hae un dae sand to Su-yeang, chun river from Song jeang line, recently it is assumed that it go to Hae un dae on the ground of insufficient evidence in diameter, specific gravity.
5. It was known that erosions happen is spring and autumn mainly.
6. Total erosion quantity is 15000m3 and the reduction area of beach sands is 2,230㎡ from July, 1981 to June, 1982
7. The equilibrium slope of beach sand had been step type untill 1982, 3. 17, but it has belonged to bar type since 1982.3, 17.
8. The specific gravities of the materials of sea-bed at the front of Kuk Dong hotel and the 3rd watchtower are about 2.70, Here, sands seems to be transported from land to sea at the latter, from west to south at the former.
Chun-river is guessed to be a supply source of sands. But At the front of the 1stwatch tower, the specific gravity of sands is about 2. 57, which is relative light.
considering that the specific gravity of sands is 2.573 in su-yeang river. At the front of Beach hotel the specific gravity is the smallest value of 2.54. Here, there are mainly clam-shells, so it is concluded that sands were transported from East-river「in song- Jeung.
9. In protection method of beach erosin, back sea dyke more than 10m(requirement model test) and construct 10m in width low step, is absorbed by it. It is to be desired that beach nourishment per 20,000㎥/year
10. To estimate the wave steepness and erosin quantity the equation, V= -338,727.3(H_0/L_0)+4898.2, was induced.
11. By the equation, V= -338727.3(H_0/L_0)+4898.2 total evosion quantify is 159,042㎥ from July. 79 to June, 82.
Because Busan is the city surrounded by sea, it is absolutely necessary to be able to observe the deepwater wave height by means of wave height observation stations.