(8) 



Q* = 0.033 and a = 0.09 

 o 



To calculate Qcpm > and since F < R s , there are two equivalent ways to 

 calculate QgpM • 



a. Use "correction factor" applied to monochromatic result. 

 Equation 1 for Q mono becomes 



«„o„o ■ [<32.2M0.033M5> 3 ] 1/2 exp - [j^gl tanh"'^) 



= 5.2 ft 3 /sec/ft of seawall 



From Figure 3 with ^ = t|-=- = 0.32: 

 R s 15.7 



Q. 



^^ = 0.51 (9) 



mono 



Therefore 



Q SPM = Q irr = (°- 51 ^ 5 - 2 ft 3 /sec/ft) 



= 2.65 ft 3 /sec/ft of structure (10) 



b. Program Equations 3a, 4, and 5. 



Interpolation for Q* and a 



15. In Example 1, the structure slope, wave steepness, and water depth 

 were such that Figure 2 conveniently yielded a point for Q* and a . In 

 other words, this was one of the situations Saville tested and Weggel 

 analyzed. If (as is inevitably the case) there is an interest in a situation 

 which was not precisely modeled by Saville, where H g = 4 ft and all the other 

 variables in Example 1 remain the same, then d S /H =2.5 , and 



H s /gT 2 = 4/ [(32. 2) (8)1 2 = 0.00194 . Figure 2 shows that there is no Q* - a 

 point for this situation. Interpolating between the surrounding points is 

 difficult. To see this, it is assumed that if one of the existing points was 

 missing, an interpolation for it would be necessary. A satisfactory general 



relationship between Q* and a and the dimensionless variables 



2 

 d /H' , H'/gT , and structure slope has not been found, 

 s o ' o B ' * 



16. An alternative to interpolating between dimensionless parameters 



11 



