(c) For the third condition, suppose that wave steepness is 

 expected to be most important, and that the structure is being 

 designed for a constant wave steepness of H'/gT^ = 0.0101 and 

 a maximum period of 7 seconds. 



Table 3 shows the characteristic relationship that the 

 largest runup, R, occurs for the lowest dg/H^ value when 

 H^/gT^ and dg are constant; the largest velative runup has 

 lower dimensional runup. However, Table 3 does not indicate 

 the maximum runup to be expected on this structure for the 

 given conditions; Table 1 shows the maximum (uncorrected for 

 scale effects) to be 23.5 feet when a maximum period of 7 sec- 

 onds is given. Thus, care should be exercised in determining 

 runup for a particular structure. The results of the three 

 parts of this problem are summarized in Table 4, and the calcu- 

 lated values are corrected for scale effect based on Figure 13. 



************* EXAMPLE PROBLEM 4*************- 



GIVEN : An impermeable structure has a smooth slope of 1 on 1.5 and is 

 subjected to a design wave, H ' = 5 feet (1.5 meters). Design wave 

 period is T = 6 seconds. The design water depth at the toe of the 

 structure is dg = 0.0 foot. The bottom has a 1 on 10 slope from the 

 structure toe to a depth, d = 15 feet (4.6 meters), at which point 

 the bottom slope changes to 1 on 200. 



FIND : Determine runup on the structure caused by a wave train 

 approaching normally. 



SOLUTION : The toe depth is zero, and the bottom slope is 1 on 10; 

 assuming that the more seaward 1 on 200 bottom slope approximates 

 a horizontal bottom. Figures 5, 6, and 7 are applicable, subject 

 to the value of d/H^ . 



— = — = 3 

 HA 5 



Therefore, Figure 5 is applicable; 



o 



gT2 (32.2) (6)' 



0.0043 



The relative runup for a 1 on 1.5 structure slope is determined 

 by interpolation to be 



32 



