Results and Conclusions . The Contractor was unable to achieve an 

 experimental model of the design envisaged. Two ideas were reported as 

 being too optimistic. The first related to the reciprocating machine. 

 Sliding seals could not be made to function satisfactorily at the high 

 temperatures and pressures encountered in the design. The second 

 pertained to determining the critical relationship between the internal 

 mechanics of the anchor and the soil mechanics of the seafloor. 

 Extensive and expensive developmental testing was indicated for both 

 problem areas with no assurance of success. 



Two ideas were reported to have stood up under study and evaluation. 

 The first was the multi-phase release of energy concept. The second 

 was the forward jetting of exhaust gases to assist and regulate anchor 

 embedment. 



On review of the Contractor's report, it was concluded that the 

 cost to solve the problems for successful development of this concept 

 were too great to warrant further investigation. 



The Padlock Anchor 



Background . Forthcoming constructions in the oceans at the 

 continental shelf and greater depths demand high capacity fixed-point 

 anchoring systems. Support features are needed that are capable of 

 resisting bearing as well as lateral and uplift forces. Considering 

 these requirements and the developments with explosive anchors at the 

 Laboratory and elsewhere, an approach to a fixed-point anchorage system 

 utilizing lightweight bearing pads and explosive anchors was conceived. 

 An operational feasibility program was initiated at NCEL and proceeded 

 concurrently with the other explosive anchor work underway at NCEL. 

 The objective was to develop and determine the operational feasibility 

 of an anchor system for the deep ocean that would provide a fixed 

 point (resistance to bearing, lateral, and uplift loads) and that 

 could be installed without diver assistance. The scope included the 

 conception, design, fabrication, and evaluation of a self-contained 

 anchor system that employed multiple bearing pads in conjunction with 

 explosive anchors. 



The effort, currently suspended, was reported by Dantz (1958). 

 Prominent facts about this concept are set forth here for a complete 

 picture of the anchoring program at NCEL and to convey additional 

 conclusions in light of developments since the work was suspended. 



Description . In general, the PADLOCK is a tripod framework 

 constructed of lightweight materials and supported at each leg by 

 articulated round bearing pads. To obtain resistance to uplift, direct 

 embedment anchors are incorporated into the system. The general scheme 

 of the entire system is shown in Figure 15. The bearing pads are 

 connected to the frame with ball-joints to allow the pads to maintain 

 maximum contact with the seafloor, adjusting to contour slopes of about 

 10 percent. An embedment anchor is housed above each of the bearings. 



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