for 



a(m) = 6.97(1 - e- 19m ) (25) 



1.56 



b(m) (26) 



(1 + e -i9-5-) 



where a(m) and b(m) are empirical coefficients. Equations 24 and 25 are 

 presented in nondimensional form, but the original equation of Weggel (1972) 

 was given in US customary units. 



33. The study by Jen and Lin (1971) was conducted to determine impact 

 pressures on a cylindrical tube placed in the tank. Breaking wave properties 

 obtained from these tests are expected to differ from results from other tests 

 used in the Weggel (1972) analysis. Data obtained from Reid and Bretschneider 

 (1953) were used as transition values from limiting wave steepness to depth- 

 limited breaking. A portion of the data reported by Reid and Bretschneider 

 were from Danel (1952), a study on limiting clapotis. 



34. Weggel (1972) determined a(m) and b(m) by assigning minimum and 

 maximum limits to -y h . The theoretical value of a solitary wave, 7 b = 0.78, 

 from McCowan (1891) , was used as the minimum breaker depth index, occurring 

 for m = . As m approached infinity, such as at a vertical wall, -y h was 

 assumed to be double the minimum value, 1.56, by adding the incident and per- 

 fectly reflected wave heights. Breaking wave height appears on both sides of 

 Equation 24, so an iterative approach must be used to determine 7 b . Equa- 

 tion 24 can easily be solved with the use of a computer, but otherwise the 

 form is inconvenient for hand calculations. 



35. Komar and Gaughan (1973) derived a semiempirical relationship for 

 ftb from linear wave theory where 



-1/5 



r h„ i 



Q h = 0.56 



(27) 



The coefficient 0.56 was determined empirically from laboratory data (Iversen 

 1952, Galvin 1969, and Komar and Simmons (as reported by Komar and Gaughan 

 1973)) and from field data (Munk 1949). 



23 



