When continuous wave action strikes the beach at an angle, trans- 

 port o£ the beach material occurs along the entire length of the .lit- 

 toral. On occasion, this may cause serious problems in some maritime 

 structures or in natural river mouths such as silting of harbors, the 

 formation of sandbars in river mouths and inlets. To avoid or at least 

 reduce this type of problem, the Hydraulic Laboratory of the Secretaria 

 de Recursos Hidraulicos executed a series of studies to find a structure 

 that may permit a control on the longshore transport produced by wave 

 action. Based on these studies, a new type of structure was developed 

 and tested on hydraulic models; the structure permits the accumulation 

 of littoral material in volumes up to 30 times as large as the volume 

 retained by conventional breakwaters and spur dikes or jetties. This 

 paper deals with the definition of the size of breakwaters depending on 

 wave characteristics and the slope of the beach. The experiments lead- 

 ing to the recommendations given in the paper were conducted on estuaries 

 with and without sediment transport. 



43. FOSTER, D.N., "Breakwater Stability: Kirra Beach," Technical Report 

 No. 72/13, Water Research Laboratory, University of New South Wales, 

 New South Wales, Australia, 1972. 



Keywords: Armor stability, Australia (Kirra Beach-Queensland), 

 Foundation design. Hydraulic model (two-dimensional). 

 Local scour, Rubble mound. Wave overtopping. Wave reflec- 

 tion. Wave transmission 



Model tests have been undertaken to investigate the stability, wave 

 transmission, and wave overtopping for the proposed offshore breakwater 

 at Kirra Beach, Gold Coast, Queensland. The results indicate that the 

 breakwater will be effective under all wave conditions. Some damage 

 which will require maintenance occurs when high waves are superimposed 

 on high storm surge. 



44. FRIED, I., "New Coastal Works at Nahariya (Israel) - Beach Protection 

 and Development," The Dock and Harbour Authority, Vol. XLV, No, 532, 

 Feb, 1965, pp. 323-326. 



Keywords: Accretion, Armor stability, Compartmented breakwater. Currents, 

 Gabions, Israel (Nahariya), Local scour. Recreation, Rubble 

 mound. Segmented breakwater. Structural dimensions 



The coastal installation at Nahariya, which consists of a low break- 

 water and a central groin, proved successful from the stability viewpoint 

 and for the purpose of creating a stretch of protected sandy beach and 

 foreshore. Two shallow-water basins, protected from wave action and easily 

 accessible to bathers, were formed in the lee of the breakwater; these 

 basins also served as terminals for small craft and cruising launches dur- 

 ing the summer season, thus supplying additional attraction to vacationers. 



The rubble-mound breakwater has withstood storm wave onslaughts and 

 requires only slight periodical maintenance, mainly at the heads. Its 



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