wave generator blade. These reflected waves created a partial standing 

 wave in the wave tank during certain wave conditions. The amplitude of 

 the standing wave was usually small compared to the incident wave height 

 but did require special considerations when determining the incident and 

 transmitted wave heights and the peak and average mooring loads. Wave 

 and mooring force record analysis is discussed in Section IV. 



Several attempts to moor the breakwater failed due to either the 

 mooring line breaking, or the anchor-pulley system pulling loose from 

 the tank floor. The front mooring line was a flexible cable with a 

 rated breaking strength of 3,700 pounds (1,678 kilograms). Despite this 

 strength the cable broke three times during the testing period. The 

 failure was caused by fatigue of the line at the pulley. A larger 

 diameter pulley should solve this problem in future tests. 



The front anchor was originally installed in the tank by jacking 

 5.08-centimeter-diameter (2 inches) pipes across the tank bottom (Fig. 

 11). This system was soon found inadequate as it was pulled away from 

 the floor with a force of 1,200 pounds (544 kilograms). (Maximum loads 

 measured during the test period exceeded 2,000 pounds.) The anchor- 

 pulley system was then bolted to the floor and was able to withstand 

 the larger forces encountered later in the study (Fig. 10) . 



Figure 11. Original anchor-pulley system used at the 

 beginning of the study. 



22 



