LARGE PLASTIC DEFORMATION OF THIN SPHERICAL SHELLS WITH REINFORCED OPENINGS.
ILLINOIS INST OF TECH CHICAGO DEPT OF MECHANICS
Pagination or Media Count:
The large deformation behavior of a membrane spherical shell subject to internal pressure loading is investigated. The shell contains a hole at the apex which is reinforced by an idealized thin ring. The incremental theory of plasticity is employed, effects of geometry changes and isotropic strain hardening are included and elastic strains are neglected. Solutions for loads up to the tensile instability load are obtained for the Tresca and von Mises yield criteria and associated flow laws. A complete solution in closed form is derived for shells having openings with sufficiently heavy reinforcements for the Tresca criterion. A numerical procedure and associated computer program, based on solution of the rate equations are derived for shells obeying the von Mises yield criterion. The latter procedure is valid for all but very light reinforcements. Numerical results are obtained which provide an indication of the effect of geometrical and material parameters on the instability pressure. The instability pressures for a range of shells are compared to their yield point loads. Comparisons are also made between predictions of the von Mises and Tresca theories and between theoretical and experimental results. Author
- Structural Engineering and Building Technology