distance was found to increase for small values of the surf similarity param- 

 eter. Penetration distance normalized by deepwater wave height showed no 

 dependency on the surf similarity parameter and appears to be dependent on 

 local wave height only. 



181. Vortex area was measured at the plunge point for 34 tests with the 

 seaward bar face angle fi^ < 10 deg. The plunge point was chosen because of 

 its uniqueness to every breaking wave, and it is the point of vortex forma- 

 tion. Vortex area was found to increase with values of the surf similarity 

 parameters and approach an asymptotic value for waves in the collapsing 

 region. 



182. Wave reflection was measured seaward of the bar for all tests and 

 was found to increase for steeper bars, which was expected, although reflec- 

 tion did not notably increase with bar slope. Reflection coefficients from 

 the experiment were compared with relationships of Miche (1951) and Battjes 

 (1975) developed for plane slopes. The equation of Miche overpredicted re- 

 flection for most of the experimental data. The Battjes equation predicts 

 increasing reflection with the surf similarity parameter; however, measured 

 values plotted as near-constant and were independent of the surf similarity 

 parameter. Reflection coefficients were also correlated with the reef reflec- 

 tion parameter of Ahrens (1987) developed for reef- type breakwaters. The 

 Ahrens equation gave better agreement, but the equation did not fully repro- 

 duce the trend. A parameter to quantify wave reflection from bars and reefs 

 was not identified, and additional study is required. 



183. Wave runup was measured for all tests. Runup was normalized by 

 deepwater wave height and plotted as a function of seaward bar angle, but 

 seaward angle showed little effect on runup. Wave runup was also constant, 

 but scattered, if plotted versus the surf similarity parameter; however, runup 

 was found to increase with the surf similarity parameter if the beach slope of 

 1/30 was used to compute £ instead of seaward bar angle. The average runup 

 normalized by H was 0.76£ o , whereas Battjes (1975) found that R/H 



= 1.0£ o . Lower measured values of runup could result from additional energy 

 dissipation caused by bars; however, runup was also lower than predicted by 

 Battjes for the present plane-slope tests. A complete analysis of wave height 

 decay and setup is required to reach a relationship for runup for barred 

 profiles . Wave data were collected through the surf zone and are presented in 

 Appendix C . 



146 



