CONCLUSIONS 



This brief discussion and the examples presented suggest that proper 

 modeling of the deep sea mooring problem (and perhaps shallow water problems 

 as well) requires very careful consideration of the nonlinear dynamics of the 

 mooring lines. At present, this means that time domain models are preferred 

 above frequency domain models. This further means there is a need to develop 

 appropriate time domain models of the ships, platforms, buoys and other bodies 

 used and to develop the appropriate description of the environment. It may 

 also mean that there is a need to develop new solution techniques. Although 

 not dealt with in this discussion, low frequency effects such as wave induced 

 drift forces and swells acting in combination with wind and waves may require 

 that large displacement responses of the mooring be considered even in the 

 situations where the frequency domain solution may be an adequate model of the 

 first order wave responses. 



REFERENCES 



1. Webster, R. L. , "Finite Element Analysis of Deep Sea Moors and Cable 

 Systems," Preprint 3033, ASCE Fall Convention and Exhibit, San Francisco, 

 California, Oct. 17-21, 1977. 



2. Webster, R. L. , McCreight, W. R. , "Analysis of Deep Sea Moor and Cable 

 Structures," Paper OTC 3623 Presented at the 11th Annual Offshore 

 Technology Conference, Houston, Texas, 30 April- 3 May 1979. 



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