left without buttressing for subsequent storm events. Based on these results 

 and discussion with the Los Angeles District, it was decided that the test 

 should be continued using Hydrograph B (Table 3). During testing of Hydro- 

 graph B, deterioration of the 25-ton buttressing stone continued and addi- 

 tional separation and displacement of dolos occurred in the lower seaward 

 quadrant. Photos 187-189 show the structure after cumulative testing of 

 Hydrograph A and B. Based on the overall test results, it appears that the 

 stability of Plan 24 is questionable. 



55. Plan 25 (Plate 27 and Photos 190-192) utilized the best merits of 

 Plan 18 and Plan 24. A trench, approximately one dolos wide, was excavated 

 starting above water at the end of the existing concrete cap and ending at 



-1 ft mllw. A rock buttress, consisting of 25-ton armor stone two layers deep 

 and about 60 ft wide, was then placed around the outer perimeter of the sea- 

 ward transition, starting at the end of the trench and proceeding below water 

 to a depth of about -30 ft mllw. Special placement was used for the dolos 

 toe units. After the dolosse were placed, voids in the trench were backfilled 

 with material left over from the excavation. A total of 420 42-ton dolosse 

 and 200 25-ton armor stone were placed. Plan 25 was subjected to the abbre- 

 viated hydrograph with marginal results. The rock buttress sloughed off to 

 about a water depth of -5 ft mllw. Four dolosse were displaced at the seaward 

 transition toe approximately where the trench ended and there was additional 

 separation in this area. Photos 193-195 show the structure after testing. 

 Although Plan 25 appeared questionable, it was felt worthwhile to continue 

 testing. Plan 25 was rebuilt and subjected to Hydrograph A. A total of 412 

 42-ton dolosse and 154 25-ton armor stone were placed. The structure sur- 

 vived the storm up to the +10 ft swl where damage originated at the end of 

 the trench. The damage progressed shoreward as the storm continued and a 

 total of 14 dolosse were displaced. At this time, it was determined that the 

 trench should extend into deeper water. Photos 196- 198 show the structure 

 after testing with Hydrograph A. It was felt that the dolosse movement was 

 extensive enough to preclude acceptability of this plan. 



56. Plan 26 (Plate 28 and Photos 199-201) was similar to Plan 25, ex- 

 cept that the trench ended at a depth of -5 ft mllw and the rock barricade 

 started at -2 ft mllw. A total of 410 42-ton dolosse and 152 25-ton armor 

 stone were placed. Plan 26 was subjected to Hydrograph A. There was some 

 separation of units along the shoreward transition and three units were 



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