Saville (1963) tested a large number of similar rough structures with a 

 1 on 2 front-face slope for a proposed breakwater at Point Loma, California. 

 Most of Saville's breakwater models had a crest elevation near the Stillwater 

 level, so wave transmission in most of the tests was primarily due to overtop- 

 ping. Some of the breakwaters tested were first modeled in the large wave tank 

 at the Coastal Engineering Research Center (CERC) , then re-tested at a smaller 

 scale to examine scale effects. Some tests were repeated with otherwise 

 identical permeable and impermeable breakwaters to assess the influence of 

 wave transmission through the permeable breakwaters and wave transmission by 

 overtopping. The breakwater crest width was also varied over a wide range of 

 values to determine the influence of width on the wave transmission coefficient. 

 Since wave reflection coefficients were not measured, the burst method was used 

 during testing to avoid laboratory effects caused by re-reflection of waves 

 from the generator blade. 



Lamarre (1967) measured wave transmission by overtopping for a structure 

 with a comparatively narrow crest width and 1 on 1.5 structure slopes. Wave 

 conditions and the height of the structure were varied. 



Goda (1969) tested vertical, smooth impermeable structures for wave 

 transmission by overtopping. The breakwater crest width was varied and a 

 wide range of submerged and subaerial structure heights and a number of wave 

 conditions were tested. Wave reflection coefficients were measured to deter- 

 mine the incident wave height acting on the structure. A nonlinear empirical 

 equation was developed for predicting wave transmission coefficients. In this 

 formula the transmission coefficient is a function of the ratio of the break- 

 water freeboard to the incident wave height and two empirical coefficients, 

 where the coefficients are related to structure geometry and the relative 

 water depth. 



Davidson (1969) tested a 1 on 40 scale model of a breakwater proposed for 

 Monterey Harbor, California. The breakwater had tribar armor units and 

 experienced a combination of wave transmission over and through the structure. 



Cross and Sollitt (1971) developed a semiempirical model for wave trans- 

 mission by overtopping of subaerial breakwaters. The model was compared to 

 Lamarre 's (1967) data for a smooth impermeable structure with a 1 on 1.5 front- 

 face slope. Cross and Sollitt 's model suggests that wave transmission by 

 overtopping is a nonlinear function of the ratio of breakwater freeboard to 

 runup. Examination of Saville's (1963) data suggests that a linear model would 

 form an upper envelope for wave transmission over rough structures. 



Keulegan (1973) measured wave transmission through a number of vertical- 

 faced permeable breakwaters using a wide variety of materials and wave 

 conditions. Comparison of results led to development of a method for design- 

 ing scale models that consider scale effects. 



Sollitt and Cross (1976) tested wave transmission through a permeable 

 rubble-mound breakwater and used this information to develop an analytical- 

 empirical model. 



Bottin, Chatham, and Carver (1976) tested 1 on 22 rubble-mound scale and 

 concrete armor unit breakwaters proposed for Waianae Harbor, Hawaii. Wave 

 transmission consisted of a combination of wave transmission by overtopping 



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