Operation VII - Port Hueneme, sandy-silt . The objective of this 

 operation was to conduct holding capacity breakout tests in a cohesionless 

 seafloor under the best control conditions possible with available 

 equipment. Operations were conducted aboard the NCEL warping tug in 

 water depths within the 40 to 60 foot range. The location was the NCEL 

 shallow water test site near Port Hueneme in the Santa Barbara Channel. 



For each test, the warping tug was in a tight 2-point moor. The 

 anchor assembly was lowered to the seafloor and the vibrator was 

 activated by a generator onboard the tug to eliminate battery recharging. 

 After the anchor was embedded, divers removed the vibrator and bolted 

 on a lifting padeye through which test loads could be applied directly 

 to the anchor shaft. A 20- foot nylon line was placed in the anchor cable 

 to attenuate the dynamic effects caused by wave action. Then, loads 

 were applied using the three-drum winch on the tug and measured with 

 a strain gaged load cell. Line tensions were recorded continuously 

 with a pen-type strip chart recorder. Displacements during breakout 

 were not measured; however, diver observation was used to determine 

 maximum anchor embedment for each test prior to breakout. 



Five successful embedments were achieved that resulted in four 

 successful breakout tests. A mechanical linkage failure during one 

 test prevented the embedded fluke from being extracted. Embedment 

 depths ranged from 2 to 7 feet measured from the seafloor to the 

 centerline of the fluke. Breakout forces ranged from 18 kips for the 

 fluke embedded Ih feet to 70 kips for a fluke embedded 5% feet. The 

 fluke that was embedded the deepest (6*5 feet after keying) is the one 

 that broke off and was lost. It resisted forces to 62 kips before 

 the linkage connector failed at the fluke. 



Operation VIII - Pitas Point, clay-silt . The objective of this 

 operation was to conduct holding capacity breakout tests in a seafloor 

 sediment that exhibits plastic behavior under the best control conditions 

 possible with available equipment. Operations were conducted aboard 

 the USS Molala (ATF 106) in 95 feet of water. The location was the 

 Pitas Point test site in the Santa Barbara Channel near Ventura. Seas 

 were calm throughout the operation period. 



The Molala was anchored in a tight 2-point moor during all testing. 

 For each test the vibrator was activated and powered through an electrical 

 cable leading to a DC generator on the ship. The surface power was used 

 to eliminate the necessity of recharging the batteries for each test. 

 The vibrator was allowed to run until the maximum embedment was achieved 

 as limited by sediment strength or vibrator failures. Penetration during 

 the vibration phase was measured using the displacement monitoring 

 system. Direct uplift loads were applied with the ship's capstan pulling 

 through the salvage beach gear (an 8-to-l block and tackle arrangement). 

 Both the upward displacement of the anchor fluke and line tensions were 

 measured and recorded continuously. 



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