For steel against steel with no galling, the friction coefficient is 

 0.15, as presented in Carmichael (1950), giving 



F. S. =w 1.624 H/T,, 



o 



If the anchor holding capacity (H) is assumed to be 148,000 pounds (660 

 kN) (as conservatively estimated above), the factors of safety for the 

 mooring legs at the two sites are as follows: 



F. S. for 

 Design load, equalized pair 



Site T B , lb (kN) = 1.624 H/Tg 



Permanent 152,000 (680 1.58 



Temporary 115,000 (510) 2.08 



These values compare favorably with the a priori required factor of 

 safety of 1.5, and also were considered highly satisfactory in view of 

 the high degree of conservatism incorporated into the assumptions of 

 sediment characteristics made in estimating anchor holding capacity. 



The general layout of a propellant anchor mooring leg is shown in 

 Figure 6. Legs of this configuration were incorporated into mooring 

 designs, and construction drawings were prepared for the temporary and 

 permanent sites by PACDIV. 



The single two-anchor hookup shown in Figure 7 was used at the 

 temporary site. At the permanent site, a short length of chain was 

 added between the buoy and the load equalizer to place the equalizer 

 below the draft depth of ships using the facility. Also, two 750-pound 

 (3.3 kN) LWT anchor backlegs were added to retain the buoys in their 

 desired position when not in use, and a slack backup leg consisting of 

 two 6,000-pound (27 kN) STATO anchors and three shots of chain was added 

 to provide emergency protection in the event of failure of one or both 

 propellant anchors; this configuration is shown in Figure 8. On the 

 turning point leg at the permanent site, four propellant anchors were 

 used, with the outer two connected through an equalizer; the LWT and 

 STATO legs were omitted. 



INSTALLATION EQUIPMENT AND PROCEDURES 



Included in this section are the vessels, shipboard load-handling 

 equipment such as cranes and winches, the diver assistance used to 

 effect installation, and the procedures associated with their use. 

 Details of procedures and equipment were described more fully in the 

 Operation Plan presented by Underwater Construction Team-One (1975); 

 hence, the description given here is intended to summarize and to update 

 that given previously. 



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