Limit Analysis and Design of a Semi-Submerged Concrete Hull for an Ocean Thermal Differences Power Plant

Utilizing the concepts of limit analysis, and ultimate strength of concrete, a design approach for large diameter immersed reinforced concrete cylindrical hulls has been developed. The method is applied to the design of a semi-submerged ocean thermal differences power plant. For the structure under consideration which consists of an outer and inner hull, separate operating and maintenance conditions were assumed for design. Equilibrium equations, and an iteration method to determine plastic moments, axial forces and shears corresponding to a collapse condition have been developed. Computer results for the outer and inner hull are tabulated for the two loading conditions based on design thickness of 3 ft. For a given thickness, details of reinforcing are given, and an admissible interaction diagram for moment and axial load to satisfy the various loading conditions is presented.