the deck, sides, bottom, and corners as part of the monitoring system. The 

 concrete pour began at dawn; by sunrise the 4-3/4-in. -thick bottom had been 

 completed. The styrofoam blocks that served as the interior forms were then 

 dropped into place (Photograph 7). Wood two-by-fours and PVC pipe were used 

 as spacers to keep the reinforcing steel located properly between the foam and 

 the forms. Steel beams were placed across the deck; then wedges were hammered 

 in between these beams and the foam to keep the foam from floating up as the 

 sides of the float were poured. After the sides of the floats had been poured 

 to within 1 ft of the deck surface, the spacers and steel holddown beams were 

 removed, leaving friction to keep the foam from rising out of the forms. The 

 deck reinforcing steel was placed, and the final stage of the pour was begun 

 (Photograph 8). Pouring and finishing of the deck completed the casting pro- 

 cess (Photograph 9). Test samples of concrete were taken throughout the pour. 

 The concrete weight varied between 131 and 134 pcf, with an average 7-day 

 strength of 4,000 to 5,000 psi and a 28-day strength of 5,000 to 6,000 psi. 

 After the concrete had cured for 7 days, each of the 10 cables composing the 

 six post-tensioning tendons was tensioned to 25,000 lb (Photograph 10). 



On May 28, 1982, the 140- ton units were lifted from the casting area and 

 lowered into the waterway (Photograph 11). The longitudinal strain gages in 

 the lower center edges of the B-float were monitored during the launching. A 

 maximum strain of 1,700 microstrains was recorded, indicating that loads were 

 about two-thirds of the yield strength of the reinforcing steel. After both 

 units were launched, they were joined end-to-end with two flexible connectors 

 (Photograph 12) and towed approximately 90 miles south to the West Point test 

 site. 

 Anchoring 



The concrete breakwater was anchored in place by ten 30-ft-long steel H- 

 piles (HP 14 by 102) (Photograph 13) embedded their full length. The pilings 

 were driven using a Vulcan 010 hammer with a 10,000-lb ram weight and an 

 8,000-lb mandrel (Photograph 14). A special fitting was attached to the 

 mandrel to hold the piling in proper alignment while it was being driven. 

 Anchor lines consisted of 1-3/8-in. -diameter galvanized bridge rope with 15 to 

 30 ft of 1-1/4- in. stud link chain at each end. Anchor line lengths were 

 sized to provide a minimum slope of 1 vertical to 4.5 horizontal. A 2,000-lb 

 concrete clump weight was attached near the upper end of each anchor line. 

 The purpose of this design was to produce a more even anchor line tension over 



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