Elastic–Brittle–Plastic Analysis of Double Layered Combined Thick Walled Cylinder Under Internal Pressure

Abstract

The elastic–brittle–plastic unified solutions of limit internal pressure are presented for doublelayered combined thickwalled cylinder by the tripleshear unified strength criterion. The unified solutions obtained in this paper are especially versatile that can take into account of material brittle softening and intermediate principal stress quantitatively. The conventional existing elasticperfectly plastic solutions, based on the Tresca yield criterion, Mises yield criterion, or twinshear strength theory, can be categorized as special cases of the present unified solutions which can overcome their shortages. Parametric studies were carried out to evaluate the influences of various factors such as brittle softening parameter, strength theory parameter, cohesion, internal friction angle, and intermediate principal stress coefficient on the unified solutions. It is shown that proper choices of failure criterion, material behavior model, and brittle softening are significant in combined cylinder design. The new solutions can be naturally degraded to the existing formula and agree well with the results of the prevailing failure criteria. It is concluded that the unified solutions have an important practical value for the optimum design and engineering application of combined thickwalled cylinder.