Determination of thin-walled cylindrical shells stability

Ante Crnjac ; Peter Crnjac

Theoretical and applied mechanics, Tome 16 (1990) no. 1, p. 25 .

Résumé

In this paper it was proved that the action of the incompleteness of the cylindrical shells in the area of elasticity differs from that in the area of plasticity. Therefore, the previous way of determining the critical force based on the incompleteness factor a is unreliable. Based on experiments conducted on a large number of samples of different dimensions, the unique method of determining the critical force of cylindrical shells without the incompleteness factor $\alpha$ to be considered, applied. This article provides the unique method of calculating the critical force or critical stress for the spheronized shells of various dimensions. Since the material of the shells and the plasticity limit $\sigma_v$ are known, the critical stress of the shell without cutout $\sigma_{\mathrm{crreal}}$ is first calculated from equation (15) or based on Figure 8. Then, if the ratio $r/R$ is known, the corresponding critical stress $\sigma_{\mathrm{cro}}$ or the critical force $F_{\mathrm{cro}}$ of the shell with a cutout is calculated on the basis of Figure 21 or from equation (21). Since this method was used on a larger number of samples, it is to be expected that subsequent investigations will give similar results.