Keywords: Armor stability. Armor units, Concrete blocks, Construction 

 procedures, Economic analysis. Foundation design, Hydraulic 

 model (two-dimensional), India (VisaRhapatnam) , Local scour. 

 Rubble mound. Ship hulls. Structural dimensions, Tetrapods, 

 Tribars , Wave overtopping 



The island breakwater at Visakhapatnam, consisting of two scuttled 

 ships filled with small stones, was protected by 2- to 6-ton stones on 

 the weather and lee sides. However, the weather side was damaged by 

 storms, exposing the ships' plates to wave action, thus warranting ac- 

 tion for reinforcing the breakwater. Tests were conducted in a wave 

 flume with various types of armor units, such as stones, tetrapods, and 

 tribars, to evolve a suitable protective layer for the breakwater and to 

 study the relative merits of various armor units. 



69. HO, S.K., "Crenulate Shaped Bays," Thesis No. 346, Asian Institute 

 of Technology, Bangkok, Thailand, 1971. 



Keywords: Artificial headlands, Crenulate-shaped bay, Hydraulic model 



(three-dimensional). Littoral transport. Movable bed, Numeri- 

 cal model. Wave diffraction. Wave refraction 



Where headlands are spaced along a sedimentary coast, the shoreline 

 between the headlands assumes a crenulate shape. If the most persistent 

 or predominant waves have a resultant direction which is oblique to the 

 headland alinement, a shape is gradually reached which is in equilibriiom 

 with the waves. The eventual development of such an equilibrium-shaped 

 bay, starting with an initial straight-line coast, was studied by means 

 of a model in which wave directions and heights were the sole variables. 

 The curved part of the equilibrium-shaped coastline was then analyzed by 

 fitting log-spiral curves. 



A typical prototype bay in fully developed condition, derived from 

 hydrographic charts, was analyzed by computer to verify that diffraction 

 and refraction combined to form the log-spiral part of the coastline. 



70. HOM-MA, M., and HORIKAWA, K., "Experimental Study of a Submerged 

 Breakwater (2nd Report) - Mechanism of Its Slumping and Maintenance 

 Measures of the Structure," Prooeedings of tTie Sixth Conference on 

 Coastal Engineering in Japan^ Japan Society of Civil Engineers, 

 1959, pp. 114-120 (in Japanese), 



Keywords: Hydraulic model (two-dimensional). Local scour, Structure 

 settlement. Submerged breakwater 



71. HOM-MA, M., and HORIKAWA, K., "Coastal Protection Works and Related 

 Problems in Japan," Prooeedings of the Seventh Conference on Coastal 

 Engineering i American Society of Civil Engineers, Vol, 2, 1960, 



pp. 904-930. 



Keywords: Compartmented breakwater, Japan (Kaike, Niigata, and Toban) , 

 Littoral transport , Submerged breakwater 



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