c. Example Problems . 



************* EXAMPLE PROBLEM 8************** 

 GIVEN : . Quarrystone rubble -mound breakwater; cot 8 = 2; cot $ = 80; 



d s =6.0 meters (19.7 feet); % = 2.0 meters (6.6 feet); 



T = 4.0 seconds; k p = 0.6 meter (2.0 feet); h c = 4.5 meters 



(14.8 feet). 

 FIND : Determine runup. 



SOLUTION : 



d s H^ h c 



rf = 3.0; f.= 3.33; /= 0.75; 

 n K r a s 



H o 2 



iF = (9. 81 )(4)* = °- 0127 - 



Assume B « 0, since the bottom slope is gentle and d s /H^ is not 

 small. The structure is a rubble-mound breakwater with a low core 

 (see Figs. 25, 26, and 27). H^/k r in this problem is less than 

 that given for dg/H£> = 3.0 in Figure 25, so the results of Figure 

 25 should be conservative. 



rn- «» 0.66 (from Fig. 25). 

 n o 



R = (0.66)0^) 

 = (0.66) (2) 



R =1.32 meters (4.3 feet). 

 Evaluation of possible scale effects is discussed in Section VI. 

 ************************************ 

 ************* EXAMPLE PROBLEM 9************** 



GIVEN : Quarrystone riprap structure; cot 6=3; 3=0; d s =6.0 meters; 

 H^ = 1.2 meters (3.9 feet); T = 4.0 seconds; k r « 0.4 meter (1.3 feet) 



FIND : Determine runup. 

 SOLUTION : 



d s H o 



n o K r 



-£7 = — 5- = 0.0076 



gT 2 (9.81) (4) 2 



94 



