height equations as a function of deepwater wave steepness. Breaker height 

 values computed using Equations 15 (Munk 1949) and 27 (Komar and Gaughan 1973) 

 are only a function of H /L ; therefore, the curves shown in Figure 6 (a-d) 

 for these equations do not change with beach slope. All the curves in Fig- 

 ure 6 (a-d) are fairly consistent in shape and range of values. Since rela- 

 tionships by Weggel (1972), Singamsetti and Wind (1980), Sunamura (1982), and 

 the present study include both beach slope and deepwater wave steepness, these 

 equations are recommended. Strictly speaking, use of Equations 19, 28, and 61 

 should be restricted to the limits given by the respective authors. 

 Review of irregular wave studies 



42. Irregular wave breaking is more complex than monochromatic wave 

 breaking. The incident wave height and wavelength vary from wave to wave, 

 as do the breaking wave height and depth. Most irregular wave breaking 

 models, for example those of Collins (1971), Battjes (1973), and Kuo and 

 Kuo (1974) , use a Rayleigh distribution of wave height and truncate the 

 distribution at H > H b , in which H b is determined from monochromatic 

 breaking wave criteria. Irregular wave breaking and decay are difficult to 

 separate because there is no distinct breaker line, and broken as well as 

 unbroken waves are present through the surf zone. 



43. Goda (1975) developed a numerical model for irregular wave defor- 

 mation based on various laboratory data. Goda used a modified Rayleigh dis- 

 tribution in which the portion of the distribution that represents broken 

 waves (H > H b ) is tapered, rather than cut, which gives a range of breaking 

 wave heights. Breaker height is expressed as: 



H b L o 



A — (1 - e" x ) (34) 



H„ H„ 



where 



x = 1.5 (1 + Ktan s m) (35) 



in which the coefficient A ranges from a maximum of 0.18 to a minimum of 

 0.12, the coefficient K = 15 , and s = 4/3 . Goda found that A = 0.17 



31 



