Equation (8) was derived empirically from small-scale experiments. 

 The calculated value of relative runup should be increased using the 

 appropriate scale-effect correction factor (discussed in Sec. VI) . 



This problem can also be solved by using the smooth-slope runup 

 curves given in Section V,l. 



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



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



EXAMPLE PROBLEM 3************** 



GIVEN : An impermeable 1 on 3 structure is fronted by a horizontal 

 bottom. The design depth at the structure toe is dg = 10.0 

 meters; design wave height is H = 3.6 meters (11.8 feet); and 

 wave period is T = 13 seconds. 



FIND : Using the flow chart in Figure 6, determine the expected relative 

 runup of a wave approaching the structure at perpendicular incidence. 



SOLUTION : The depth where wave height is measured, d^, is the same as 

 the structure toe depth, dg . 



d s 10 



gT 2 (9.8) (13) 2 



= 0.006 < 0.08 



Thus, H ^ H^ and H^, must be calculated as noted in the flow 

 chart. H^ = H/K s ; Kg may be determined from equation (2) or from 

 Table C-l in the SPM. To use the table, determine 



s / s 



From Table C-l, read: 



(2tt) = (0.006) (2tt) = 0.0379 



K g -jL -1.075 



Calculate: 



Then, 



and, 



IT -7 £ 



% = — = 1 q 75 = 3.349 meters (11.0 feet) . 



H o 3.349 



0.031 tan 2 G = 0.031(0. 333) 2 = 0.00344, 



H ' 



-£5- = 0.002 < 0.031 tan 2 6 = 0.0034 . 

 gT 2 



28 



