IV. EXPERIMENTAL RESULTS 



1. Wave Record Analysis . 



Typical wave records for the incident and transmitted waves are shown 

 in Figures 12, 13, and 14. For the majority of the tests conducted, the 

 wave height was uniform for the first 10 waves or so before the effects 

 of reflected waves we.re- ^served. This allowed an accurate determination 

 of the average value of the incident and transmitted wave heights to be 

 made before reflected waves from the beach and wave generator modified 

 recorded values. The wave records for the steeper wave conditions (Fig. 

 12) were more complex due to nonlinear effects. Incident and transmitted 

 wave heights for these records represent an average of the highest one- 

 third of the waves before the reflected waves reached the gage. All wave 

 records were analyzed by hand and independently checked to ensure accurate 

 determination of the values reported. 



2. Mooring Force Record Analysis . 



Maximum (peak) and average forward mooring forces associated with each 

 test condition were measured from the mooring force records. The peak- 

 anchor force was taken as the maximum load recorded during the 5-minute 

 test. This value occurred at the beginning of most of the records as 

 shown in the forward load record in Figures 12 and 13. However, for a 

 few conditions the peakload did not occur until after reflected waves 

 had reached the gage (Fig. 14). 



In addition to the peak force an average force v;as obtained by averag- 

 ing the highest one-third of the cyclic peakloads. This value represents 

 conditions that include the reflected waves. As shown in Figure 12, the 

 average force is fairly constant during the part of the record when reflec- 

 ted waves were occurring. However, for some wave tests, the average force 

 increased and decreased with time (Fig. 14) . This varying force appeared 

 to depend on the test period, water depth, reflected wave height, and 

 breakwater width. 



3. Results . 



Wave measurements and mooring line force measurements for all tests 

 are listed in the Appendix. Since several test conditions were repeated 

 to assure quality control over the experiment, the composite incident 

 wave height, transmitted wave height, and peak and average loads are 

 also listed in the Appendix for each test condition. The transmission 

 coefficient, K^, was obtained by dividing the transmitted height, H^, 

 by the incident height, H^. The wavelength, L (in meters), was calcu- 

 lated from the wave period and water depth using linear wave theory. Wave 

 steepness, H^/L, was found by dividing the incident height by the wave- 

 length. W/L represents the ratio of the breakwater width to the wave- 

 length. Peak force, Fp, and average force, F^, are shown in kilograms 

 per meter of breakwater length parallel to the wave crest (uncorrected 



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