Integrated Physical Model for Cylindrical Shells

An integrated physical model for closed thin‐walled cylindrical shells under nonaxisymmetric pressure is proposed. The model, based on the interaction of the beam‐plate bending, the membrane, and an equivalent ring foundation load‐carrying mechanism, is capable of capturing the overall physical behavior of the shell under both lower $(n=0\text{,}1)$ and higher load $\left(n>1\right)$ harmonics. The model converges to the beam on elastic foundation model $(n=0)\text{,}$ to the Bernoulli‐Euler beam model $(n=1)\text{,}$ and to the slice‐beam on elastic foundation model $\left(n>1\right)\text{.}$ It also accounts for the beam‐plate bending behavior of the shell (even though only approximately for $n>1$). The load‐carrying mechanisms activated along the cylindrical shell are determined by the shell geometry and the load harmonic under consideration. For rather shallow and/or thin cylindrical shells and for the lower load harmonics $(n=2\text{,}3)\text{,}$ membrane action is shown to represent the dominating load‐carrying mechanism throughout the cylinder. The corresponding edge disturbances, absorbed by a rather weak ring foundation, have very long decay lengths. As the shell becomes thicker and/or taller, and especially for the higher load harmonics $n=6\text{,}7\text{,}8\text{,}$ the ring action progressively becomes active over a larger portion of the shell.