STABILIZATION OF COAST BY CONSTRUCTION OF HEADLANDS ON THE KASHIMANADA COAST, JAPAN

T. Uda; M. Sumiya; H. Sakuramoto

doi:10.9753/icce.v21.207

STABILIZATION OF COAST BY CONSTRUCTION OF HEADLANDS ON THE KASHIMANADA COAST, JAPAN

Coastal Engineering Proceedings ◽

10.9753/icce.v21.207 ◽

1988 ◽

Vol 1 (21) ◽

pp. 207

Author(s):

T. Uda ◽

M. Sumiya ◽

H. Sakuramoto

Keyword(s):

Pacific Ocean ◽

Beach Erosion ◽

Wave Direction ◽

Shoreline Position ◽

Follow Up Study ◽

Field Investigations ◽

The Pacific ◽

The Pacific Ocean ◽

Periodic Changes

Eleven artificial headlands were constructed on the OhncKashima Beach facing the Pacific Ocean to prevent further extension of beach erosion and to form the dynamically stable beach. This paper summarizes the results of the follow-up study of the new works applied on the actual coast. Field investigations such as bottom sounding around headlands and aerial photographing were conducted. It was found that the periodic changes of the shoreline configuration correpsonding to seasonal change of the wave direction exist on this coast and these variations of the shoreline position can be reduced by the effect of these headlands.

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ON THE SCATTERING OF CONCRETE ARMOUR UNITS OF DETACHED BREAKWATERS DUE TO WAVES

Coastal Engineering Proceedings ◽

10.9753/icce.v20.145 ◽

1986 ◽

Vol 1 (20) ◽

pp. 145

Author(s):

H. Kohno ◽

T. Uda ◽

Y. Yabusaki

Keyword(s):

Beach Erosion ◽

Aerial Photographs ◽

Field Observations ◽

Suruga Bay ◽

Change Rate ◽

Shoreline Position ◽

The Pacific ◽

Concrete Blocks ◽

The Pacific Ocean ◽

Plane Area

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.

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BEACH CHANGES CAUSED BY EXTENSION OF OFFSHORE BREAKWATER AND LIMITATIONS OF ARTIFICIAL REEFS CONSTRUCTED AS A MEASURE AGAINST BEACH EROSION

Coastal Engineering Proceedings ◽

10.9753/icce.v33.sediment.117 ◽

2012 ◽

Vol 1 (33) ◽

pp. 117

Author(s):

Yasuhito Noshi ◽

Takaaki Uda ◽

Yukiyoshi Hoshigami

Keyword(s):

Pacific Ocean ◽

Protective Effect ◽

Beach Erosion ◽

Contour Line ◽

Artificial Reefs ◽

Change Model ◽

Fukushima Prefecture ◽

The Pacific ◽

The Pacific Ocean ◽

Sheltering Effect

Beach changes on a pocket beach of 6.5 km length bounded by Ryugu and Unoko Points facing the Pacific Ocean in Fukushima Prefecture were investigated using the contour-line-change model. The shoreline recession and excess deposition of sand in the central and southern parts of the study area, respectively, between 1980 and the 1990s were triggered by the wave-sheltering effect due to the extension of the offshore breakwater of Hirakata fishing port south of the study area. Although artificial reefs were constructed in the eroded area of the study area as a measure against beach erosion, their protective effect was limited because the wave-sheltering effect of the offshore breakwater of the fishing port is much larger than that of the artificial reefs.

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