Influence Of Compressive Strength And Wall Thickness On Behavior Of Concrete Cylindrical Hulls Under Hydrostatic Loading

Influence of Compressive Strength and Wall Thickness on Behavior of Concrete Cylindrical Hulls Under Hydrostatic Loading

Sixteen unreinforced, cylindrical concrete hull models of 16-inch outside diameter were subjected to external hydrostatic loading to determine the effect of concrete strength and wall thickness on implosion and strain behavior. The test results showed that an increase in concrete strength of 70% produced an average increase in implosion pressure of 87%, while increases in hull wall thickness by factors of 2 and 6 produced increases in implosion pressure by factors of approximately 2 and 11, respectively. Changes in concrete strength had little effect on strain behavior; however, strain magnitudes generally increased with increasing wall thickness when comparisons were made at a constant percentage of P(im). Design recommendations are presented to aid in the design of cylindrical concrete hulls for underwater use.

Technical Report

Influence of Length-to-diameter Ratio on Behavior of Concrete Cylindrical Hulls Under Hydrostatic Loading

Fourteen hollow concrete cylindrical hulls ranging in length from 8 to 128 inches and having an outside diameter of 16 inches and a wall thickness of 2 inches were subjected to hydrostatic loading to determine the effect of cylinder length-to-outside-diameter ratio (L/D o) on the implosion pressure and strain behavior, and the distance from the edge of the cylinder in which radial displacement was influenced by the end closure. Hemispherical end closures were joined to the cylinders with epoxy, silicone rubber, or steel dowel pins and epoxy. The uniaxial compressive strength of the concrete averaged approximately 9,500 psi. (Author).