One of the features of a recent Monaco Government modernization 

 scheme was an artificial beach in Larvotto Bay at Monte Carlo, which was 

 to offer first-class bathing and amenities matching the very high stand- 

 ard of urban development planned for the area. Most of the Monaco coast 

 is rocky and very steep, and the only places with a gradual slope down 

 to the sea were a few very inferior beaches the waves had formed with 

 widely varied materials from local builders' rubble dumps. 



187. TOYOSHIMA, 0., "A Method for Constructing a Breakwater Away From 

 Shore," Prooeedtngs of the 15th Conference on Coastal Engineering 

 in Japanj Japan Society of Civil Engineers, 1968, pp. 169-174 



(in Japanese) . 



Keywords: Accretion, Detached breakwater. Foundation design, Segmented 

 breakwater 



188. TOYOSHIMA, 0,, "On the Height of Offshore Breakwaters," Proceed- 

 ings of the 16th Conference on Coastal Engineering in Japcm^ Japan 

 Society of Civil Engineers, 1969, pp. 247-252 (in Japanese). 



Keywords: Foundation design. Segmented breakwater 



189. TOYOSHIMA, 0., "Statistical Considerations of Detached Breakwaters," 



Proceedings of the 17th Conference on Coastal Engineering in Japan^ 

 Japan Society of Civil Engineers, 1970, pp. 323-330 (in Japanese). 



Keywords: Detached breakwater, Japan, Segmented breakwater 



190. TOYOSHIMA, 0., "Detached Breakwaters," Coastal Engineering for the 

 Practicing Engineer: Erosion^ Chapter 8, 1972, pp. 227-317 (in 

 Japanese) . 



Keywords: Accretion, Akmon armor units. Composite structure. Concrete 



structures. Continuous breakwater. Design guidelines. Detached 

 breakwater, Downdrift beaches. Environmental concerns. Founda- 

 tion design, Hexaleg blocks. Hollow tetrahedron. Hydraulic 

 model (three-dimensional), Japan (Aomori, Atsumi, Ishizaki, 

 Kaizaka, Kanzaki, Kineichiyo, Maizuru, Maji, Niigata, Niishiki 

 Beach, Onejime, and Zenigamezawa) , Littoral transport. Local 

 scour. Movable bed. Rubble mound. Segmented breakwater. Struc- 

 tural dimensions. Structure settlement. Submerged breakwater, 

 Tetrapods, Tombolo, Wave attenuation, Wave diffraction. Wave 

 setup. Wave transmission 



The chapter gives a comprehensive look at beach erosion, its causes 

 and possible countermeasures , and examines in detail the use of detached 

 breakwaters. Topics discussed include wave attenuation effects and sand- 

 trapping mechanisms of these structures. The dimensions and effectiveness 

 of the existing detached breakwaters in Japan are listed in tabular form. 

 Design guidelines are given and case histories are described. 



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