Hydrodynamic Response 
Dynamic Response of Modules, Sections and Platforms. Assembly at- 
sea of modules and sections must be planned around expected motions 
(amplitude and frequency) of these bodies in the seaway. In addition, 
second order design of MOBS candidates must consider such motion depend- 
ent loads as hull slamming, hydrostatic forces due to cyclic submergence 
above and below the mean hull water line, payload inertial forces on 
decks and bulkheads and the inertial effects of the added-mass on the 
hull bottom. Motion (in both regular and random seas) will be predicted 
by analytical means, if possible, but experimentation will likely be 
necessary for determing the effects of damping and added-mass. The 
latter effects will vary with each assumed buoyant support configuration. 
Eventually the most promising candidate(s) will be modeled, and the 
analytical predictions checked experimentally in a suitable wave tank. 
Analytical studies, backed by results from towing tests, will 
demonstrate the feasibility, or lack thereof, of towing or propelling 
large platform modules/sections. Directional stability will be evaluated 
at the same time these studies are conducted. Finally, the estimates 
of platform drag, hydrodynamic as well as aerodynamic, will be used as 
input in the design of mooring systems for alternative concepts. 
Station Keeping. Alternatives for maintaining the position of 
platforms should be investigated. Wind and current loadings should be 
determined analytically and experimentally. A comparison of alternative 
station keeping techniques would consider conventional moorings and 
anchors, unconventional systems, and dynamic positioning. 
Operational/l.ogistic Requirements 
Construction Sites. The objective would be to investigate the 
availability of construction materials, labor and equipment at sites 
suitable for construction. Factors to be considered in selecting a 
construction site include the potential and need for establishing (1) 
production plants (for the production of aggregate, cement, concrete 
mix and concrete products), (2) assembly plants (utilizing heavy 
materials handling and prestressing equipment), and (3) launching 
facilities. The study should consider potential sites in the Continental 
United States and Hawaii and be extended to include remote sites, par- 
ticularly those in the Western Pacific. 
Final assembly at sea will require work systems such as floating 
cranes and ships and barges for support of construction personnel and 
equipment. Estimates ~1ould be made of the logistic burden, i. e., 
types, numbers, range and duration of support vessels, and the critical 
resupply factors essential for maintaining the flotilla at remote sites. 
Human Factors. Essentially, this considers the human factors 
engineering necessary to operate and maintain the platform on station; 
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