of the mooring lines. Some of these data were used for 

 validation in References 2 and 4. To complete the val- 

 idation, however, data are needed with forced horizontal 

 motions at the tops of the mooring lines. 



Based on these experiments. .!';; following conclusions are drawn: 



1. In terms of ranges over which the dynamic responses are 

 linear, (id' s where load responses to a sinusoidal 

 motion in^:'t '2main sinusoidal, motion amplitudes of 

 0.043 foot produced mostly linear responses; whereas, 

 amplitudes of 0.109 foot produced mostly non-linear 

 responses. Compared to the model mooring depth of 9 feet, 

 bo£h of these amplitudes are large. Also, non-linear 

 effects increased with frequency and differ with mooring 

 line material. Experiments with more amplitudes and 

 frequencies are needed to better define the linear, 

 dynamic response ranges. 



2. Non-linear effects, su:h as out-of-plane n-otion, were 

 observed on the models with bending stiffness, even when 

 the dynamic load responses appeared linear. 



3. For vertical motion input at the top of the model moorings, 

 the horizontal and vertical load response ratios exhibited 

 the following: 



a. Trends in the load response ratios with frequency shown 

 in Figures 11 through 21 were similar to those expected 



from theory when the equilibrium tension is sufficiently 



2 

 large, 



b. Preload effects were influenced by bending stiffness 

 in that: 



(1) For the flexible models, load ratios increased 

 with increased preload, 



47 



