Elastostatics of Cubic Boxes Subjected to Pressure

This paper deals with the experimental stress and strain analysis of cubic boxes subjected to pressure. The models manufactured had inside-span-to-wall-thickness ratios varying from approximately 5 to 14. All internal corners had circular fillets. The experimental analysis was conducted using electrical strain gages, brittle coatings and photoelasticity. Results, given parametrically by means of families of curves representing normalized stresses are applicable to boxes of any size, made of any elastic material, provided the span-to-wall-thickenss ratio falls within the range studied. Results obtained using the theory of structures approach are included for comparison purposes and presented in a form useful to designers.

Stresses in a Pressurized Ribbed Cylindrical Shell With a Reinforced Circular Hole Interrupting a Rib

The stresses in a ribbed cylindrical shell with a reinforced circular hole intersecting one of the ribs are analyzed when the shell is subjected to internal pressure. Several experimental methods were used: brittle coatings, electrical strain gages, and the photoelastic freezing technique. The results obtained here were compared with those corresponding to a ribbed shell with a reinforced circular hole between two ribs, a ribbed shell with a nonreinforced circular hole, an unribbed shell with a reinforced circular hole, and an unribbed shell with a nonreinforced circular hole.

General Instability of Ring-Stiffened Cylindrical Shells Subject to External Hydrostatic Pressure—A Comparison of Theory and Experiment

Tests are described of a number of machined-stiffened cylinders subjected to external hydrostatic pressure, and the observed general instability strengths compared with predictions from theories of Kendrick and Nash. Agreement with Kendrick was found rather good. Results also are presented from electrical strain gages which show in detail the growth of embryonic lobes and nonlinear characteristics of deformation at the threshold of buckling. Weakening effects of imperfect circularity are discussed.