were used and located at positions designated 1, 3, 4, and 5 in Figure 3. 

 A summary of the pressure data organized by wave conditions is given in 

 Table 5. The same data organized by transducer location are given in 

 Table 6. The pressure data are given as pressure head, in feet of water, 

 relative to the Stillwater level as determined from static calibration. 



An attempt was made to compare extreme values in the pressure record 

 to extreme values of runup but little correlation was noted. However, 

 the short-record lengths may have contributed to the lack of correlation. 



V. RECOMMENDATIONS 



1. Runup Gage . 



The runup gage, while generally performing well, could be improved. 

 The reliability of the runup gage could possibly be improved by replacing 

 the mechanical relays with solid-state relays. The use of solid-state 

 relays might make it feasible to have greater resolution of the runup by 

 using more runup contacts per slope length than is possible with mechanical 

 relays. Closer spacing of contacts would be necessary to maintain the 

 same resolution (0.01 foot) on a steeper slope. Some type of circuit logic 

 which could identify relay malfunctioning would also be beneficial. 



2. Data Sample Sizes. 



Analysis has shown that the sample sizes used to compile Table 3 were 

 too small. The data analysis in Table 3 represents the upper limit of 

 complexity that can be reduced manually. For a quantitative investigation 

 of runup caused by irregular waves similar to the type encountered in 

 coastal waters, larger sample sizes of the relevant parameters will be 

 required. It is recommended that a computer-based data acquisition system 

 be used in future CERC studies of irregular wave runup. 



3. Pressure Transducers . 



The pressure transducers generally worked satisfactorily and required 

 little maintenance. Visual and photographic observations indicate the 

 thickness of the runup wedge can be measured from the pressure transducer 

 records. Future research should include quantitative verification of the 

 relationship between the pressure record and the thickness of the runup 

 layer on the slope. 



Pressure transducers were incorporated into this phase of the runup 

 study primarily to gain familiarity with their use and to assess their 

 potential value to the more advanced work on runup and overtopping. The 

 transducers used below the Stillwater level can monitor waves shoaling 

 and coalescing over the runup slope and other surf processes such as wave 

 setup and setdown. Pressure transducers located above the Stillwater level 

 on the runup slope should be useful in predicting potential overtopping 

 at their elevation. Their usefulness in predicting overtopping will be 

 verified through calibration during subsequent phases of this study. 



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