Further developments and study in the deep ocean anchoring program 

 at NCEL make it possible to view the contributions and prospects of the 

 PADLOCK system with a broader perspective. The tripod framework and its 

 rewind mechanism is a development that can be utilized to obtain 

 increased capacity of deep ocean direct embedment anchors whether they 

 be improved explosive anchors or some other type. It can accomplish 

 this increase by effectively combining and mobilizing the holding action 

 of groups of anchors in a module. Also, it can provide the bearing 

 capability needed for some constructions. Though not in the program 

 effort at the current time, the principle of operation and the hardware 

 are available for reapplication when appropriate. 



Other developments emanating from the PADLOCK program also are 

 beneficial to the ongoing effort. The stern roller is proving valuable 

 in handling loads in deep sea operations similar to those encountered 

 in placing anchors. Features of the activator unit are adaptable to 

 command other functioning parts of deep water anchors. The battery 

 power unit principle is being employed in the current vibratory anchor 

 program. 



VIBRATORY ANCHOR 



Background 



The current deep water anchoring program is centered upon the 

 vibratory anchor concept. Other anchor approaches are not excluded 

 from the program but rather are in abeyance. The anchor designs 

 discussed or elements thereof, plus still other designs may well be 

 needed and used to achieve the range of anchoring capability essential 

 to future ocean construction. However, weighing such factors as 

 current knowledge and state-of-the-art skills, the vibratory anchor 

 appears to offer the greatest early return. 



The principle of driving piles by vibration into the soil on land 

 has been employed for more than a decade. The idea of embedding anchors 

 by this method suggested itself with the successful driving of piles and 

 coring tools by vibration. Of particular note, as it applies to deep 

 water applications, was the accomplishment of obtaining core samples in 

 3000 feet of water off the California coast with a vibracorer 

 (Winterer, 1967). 



Three major considerations are favorable to the vibratory anchor 

 concept. First, it permits power to be applied throughout the 

 embedment phase of placement. Thus, it should be able to better 

 accommodate to and compensate for varying resistances as it penetrates 

 into the seafloor than a single burst of energy embedment anchor. 

 Second, by virtue of the delibrate steady embedment process afforded 

 by the extended power base of operation, the fluke design developed for 

 the free-fall anchor concept seems to be more readily adaptable to the 

 vibratory principle. Third, instrumentation to measure the amount and 

 the rate of penetration is more readily adaptable to the vibratory anchor 

 than other conceived direct embedment type anchors. This information 



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