Stability of three-layer orthotropic cylindrical shells with nonuniform pressure

Conclusions

• 1. For three-layers cylindrical shells of moderate length with not too great values of ε, between the critical value of the uniform pressure (q^* _{0, cr}) and a nonuniform pressure, given in accordance with the law (1.1), there exists the dependence

  $$q_{0,cr}<< q*_{0,cr}<< q_{0,cr} (1 + 2\varepsilon ).$$

• 2. If the pressure is uniformly distributed over the generatrix of the cylinder, but nonuniformly along the peripheral coordinate, the form of the loss of stability of the shell in the longitudinal direction cannot be described by a single half-wave cosinusoid.

• 3. The form of the bulging of a cylindrical shell in a peripheral direction, with nonuniform pressure (1.1) and with N=1.2, is determined mainly by the subcritical change in form of the shell. However, with N>2, there is a connection between the forms of the loss of stability under uniform and nonuniform loading.

• 4. The observed special characteristics in the behavior of three-layer cylindrical shells with the pressure (1.1) are common also to shells which are homogeneous over their thickness. A lowering of the shear rigidity of the filler affects the value of the critical loading, but does not introduce any significant changes into the character of the bulging of three-layer shells in comparison to single-layer shells.