more random fashion. The units along the seaward transition sustained consid- 

 erable damage for the repeat test. Photos 96-98 show the structure after re- 

 peat testing. The repeat test indicated that toe placement is critical in the 

 stability of the structure. 



42. Plan 12 (Plate 16 and Photos 99-101) was constructed with two rows 

 of 58-ton dolosse along the seaward transition of the elbow; the 58-ton units 

 along the toe were randomly placed. It was hoped that the heavier units would 

 stabilize this area without trenching. A total of 46 58-ton and 319 42-ton 

 rehabilitation dolosse were placed. The seaward transition sustained severe 

 damage during testing. Photos 102-104 show the structure after testing. 



43. Plan 13 (Plate 16 and Photos 105-107) was similar to Plan 12, ex- 

 cept some additional 58-ton dolosse were placed. Also, special placement was 

 used for the toe units. A total of 65 58-ton and 313 42-ton rehabilitation 

 units were placed. The seaward transition still sustained daimage during test- 

 ing. Photos 108-110 show the structure after testing. 



44. Plan 14 (Plate 16 and Photos 111-113) was similar to Plan 13, ex- 

 cept a trench was excavated along part of the seaward transition. A total of 

 61 58-ton and 312 42-ton rehabilitation units were placed. Again the seaward 

 transition sustained damage during testing. Photos 114-116 show the structure 

 after testing. At this time it was decided that the larger units exhibited 

 more surface area for the waves to work on and were not a feasible alternative 

 unless higher density concrete was used, which in effect, would increase the 

 weight without increasing the surface area. Since high-density model units 

 were not available to show this effect and the time limitation prevented mak- 

 ing additional model units, future efforts concentrated on finding a stable 

 section using the 42-ton dolosse. 



45. Plan 15 (Plate 17 and Photos 117-119) was constructed with a trench 

 approximately one dolos wide and about 5 ft (one-stone-diameter) deep. After 

 the units were placed in the trench, the voids between units in the trench 

 were backfilled with material left over from the excavation. Special place- 

 ment was used for the toe units. The total number of 42-ton rehabilitation 

 units was 373. Again damage exceeded acceptable limits. Although much of the 

 backfill material was scoured out during testing, placement of the backfill 

 material did improve the stability of the seaward transition. Photos 120-122 

 show the structure after testing. 



46. Plan 16 (Plate 18 and Photos 123-125) was similar to Plan 15, 



18 



