Explicit solutions are obtained, in terms of modified Bessel functions, for the problems of transverse twisting and of tangential shearing of transversely shear-deformable shallow spherical shells with a small circular hole. The relevant stress concentration factors are calculated for the entire range of a rise-to-thickness ratio parameter and a transverse shear deformability parameter. The modification of known results obtained previously by shear deformable plate theory, and by shallow shell theory without consideration of transverse shear deformation effects, is delineated.
This article presents the results of a numerical study of the stress concentration around two equal and unequal holes in an orthotropic spherical shell made of composite materials under the action of internal pressure. The influence of geometric (hole radii, shell thickness, distance between holes) characteristics, as well as material orthotropy and shear stiffness, on the stress state of spherical shells made of composite materials is studied. A numerical algorithm based on the finite element method has been developed and a software package has been implemented on a computer that allows solving the problem of stress concentration near two unequal holes in spherical shells made of composite materials.
Abstract
A process is suggested for improving the rubber-cord composite in a radial tire through precision stage-by-stage molding of its parts. This starts by casting an inner elastomeric envelope of the carcass from a liquid oligomer mix. The full molding technology uses acoustic and resonance effects to optimize the degree of order of the structure and of rubber uniformity. The resultant precision tires should have a higher degree of order of both macro- and microstructure than do present commercial tires. Reduced stress concentration in locations that have high failure rates in commercial tires are considered. A new theory, CSSOT, is used for optimizing tires from results of stress-strain cycles.
Stress-strain state of spherical shells with two unequal holes