greatest structural design problem. Either type of loading to about 40 feet can be resisted by 

 building adequate strength into the stringers and main walk attachments to accommodate 

 the cantilever bending forces. It is usually necessary to place a pile at the end of each finger 

 for longer slips. This procedure will require more guide piles to resist the windloading on the 

 whole system. However, the internal strength of each finger and connections to the main 

 walk must still be considered in the structural analysis. 



Some floating systems are being marketed that rely for lateral support on pipe piles of 

 rather small diameter driven through pipe sleeves after the system is in place (Fig. 87). The 



Figure 87. Close fitting pipe-sleeve pile guide. Piles are driven through sleeves after floating 



system is in place, 

 analysis of such systems is made complex by the flexibility of both the pipe and the floating 

 components. The resistance of the bottom materials to cantilever bending of the piles from 

 bottom is usually small, and it is necessary to consider the probability that a reverse 

 cantilever action occurs in which the pile may be considered fixed within the sleeve. A 

 simple reaction force must then resist the pile tip at some point below the mud line. The 

 sleeve and attachments to the floating framework, and the framework itself must all be 

 adequate for cantilever action in the pile. A sample calculation of the forces involved in this 

 type of guide pile is shown in Figure 88. 



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