(1.25 sec, 0.37 ft and 1.00 sec, 0.26 ft) in addition to the base tests with 

 H /L„ =0.05 . The purpose of this variation was to compare wave breaking 

 properties over a range of heights and periods for a given value of H /L . 

 These variations of the base tests are summarized in Table 8. 



Table 8 

 List of Design* Parameters for Base Test Variations 





Parameter 



1 





H /L 



T 

 sec 





H' 

 ft 



0.05 



1.25 

 1.00 



0.37 

 0.26 



Parameter 2 



fa 



deg 

 20 



Parameter 3 



Pi 



deg 



5 

 10 

 15 



* Nominal values for design purposes which were only approximated. 



116. Tests were made with base case waves without a bar for comparison 

 of breaking wave properties with barred profiles. These tests provided a 

 foundation for observing the influence of the bar on breaking wave properties. 

 The plane slope tests were also included in analysis of previous data sets to 

 obtain relationships for breaker indices and plunge distance. 



117. Wave data were collected for 2 min for all monochromatic wave 

 tests, but only 15 successive waves were analyzed. Analysis of the wave data 

 was begun after waves reflected off the concrete slope and was ended before 

 reflected waves from the wave board had returned to the bar. This procedure 

 eliminated contamination of the data from waves reflected off the wave board 

 and simulated the natural reflection of waves from the beach and bar. Break- 

 ing waves were also recorded on videotape for 2 min and quantities determined 

 visually for 10 consecutive waves using the same procedure. 



Irregular wave tests 



118. Three irregular wave conditions were generated for three bar con- 

 figurations each, as well as for the control case of no bar. A J0NSWAP com- 

 puter signal was generated for peak periods T p of 1.0, 1.5, and 1.75 sec 

 with significant wave heights H s of 0.37, 0.47, and 0.45 ft, respectively. 

 Figure 28 shows the spectral shape generated for T p = 1.75 sec , and the 

 input parameters required to generate the signal; the wave height at the wave 

 board, the water depth at the wave board, the spectral peak frequency 



73 



