AXISYMMETRIC BEHAVIOR OF A RING-STIFFENED 

 CYLINDRICAL PRESSURE HULL 



ELASTIC DEFORMATIONS AND STRESSES 



In the past, many criteria for predicting the collapse strength of a 

 ring- stiffened cylindrical pressure hull have been based on an accurate 

 knowledge of the biaxial state of circumferential and longitudinal stress 

 which results as a consequence of the uniform pressure loading. Although 

 it recently has come to be appreciated that the axisymmetric mode of 

 collapse is in reality a combined yielding and buckling phenomenon, the 

 prebuckling deformations and stresses are still a prime requisite to an 

 analysis of this and the other (asymmetric) modes of instability. 



The problem of determining the amount of external pressure that can 

 be resisted by a cylindrical shell structure before failure is precipitated 

 by axisymmetric yielding in the shell plating has been considered by many 

 investigators, anaong them Von Sanden and Giinther, and Viterbo. How- 

 ever, the criteria developed by these authors for the maximum bending 

 and circumferential stresses in the shell plating and the peripheral load 

 supported by the ring frames do not reflect properly the "beam-column" 

 effect of the hydrostatic pressure on the structure. This effect is in 

 reality the interaction between longitudinal bending and longitudinal 

 compression as a consequence of the axial portion of the hydrostatic pres- 

 sure loading. After close examination of these theories by the group at 



* Another way of looking at this is to consider it as axisymmetric buckling 

 at a reduced modulus due to the stress state. 



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