because the toe units of the seaward transition should have been subjected 

 to minimum force components acting to push the units outward from the rest of 

 the rehabilitation dolosse, for the 90-deg angle of wave attack. The seaward 

 transition still suffered severe damage. Apparently, diffraction effects in 

 this area of the breakwater caused significant forces on the dolosse. 

 Photos 48-50 show the structure after testing. 



35. Plan 5 (Plate 10 and Photos 51-53) was the same as Plan 3, except 

 that the seaward transition of the rehabilitation units extended out the east- 

 ern extension to sta 39+00. A total of 775 dolosse were placed in the reha- 

 bilitation area. The lower corner of the seaward transition still rested on 

 material in the shoal area, leaving the flukes of toe units exposed at swl's 

 of -1 and +4 ft; these toe units were subjected to considerable wave energy 

 even though they had been placed out to sta 39+00. Extensive damage occurred 

 in the area of the seaward transition. Photos 54-56 show the structure after 

 testing. 



36. Plan 6 (Plate 11 and Photos 57-59) was constructed with the reha- 

 bilitation units ending at sta 37+00. A total of 303 rehabilitation dolosse 

 were placed. This plan showed the most promise of any tested to data, as only 

 six rehabilitation dolosse were displaced in the seaward transition. Damage 

 occurred near the swl, and as the water depth was increased the damaged area 

 moved upslope. At this time it was determined that a trench might stabilize 

 toe units in the seaward transition. Note, existing dolosse that extended 

 past the end of the cap received no protection from the rehabilitation units; 

 these existing units were displaced during testing. Photos 60-62 show the 

 structure after testing. 



37. Plan 7 (Plate 11 and Photos 63-65) was the same as Plan 6, ex- 

 cept that a trench was excavated starting at the toe of the existing dolosse 

 (0.0 ft mllw) and ending a distance 100 ft from the outside of the cap at 

 -11.0 ft mllw. The trench followed a line which was perpendicular to the 

 main breakwater stem and intersected at cap at sta 37+00. The trench was 

 about 5 ft deep, i.e., deep enough that when the vertical fluke of a dolos 

 was placed vertically in the trench, it was securely supported from slipping. 

 Toe units in the seaward transition of Plan 7 were placed as in Plan 6, except 

 some of the units rested in the trench. Dolosse along the seaward transition 

 remained stable during testing. The structure was rebuilt and the test re- 

 peated. Results for the repeat tests were the same except three units were 



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