Buckling of thin‐walled cylindrical shells under axial compression

Abstract

SUMMARYLightweight thin-walled cylindrical shells subjected to external loads are prone to buckling rather than strength failure. The buckling of an axially compressed shell is studied using analytical, numerical and semi-empirical models. An analytical model is developed using the classical shell small deflection theory. A semi-empirical model is obtained by employing experimental correction factors based on the available test data in the theoretical model. Numerical model is built using ANSYS finite element analysis code for the same shell. The comparison reveals that the analytical and numerical linear model results match closely with each other but are higher than the empirical values. To investigate this discrepancy, non-linear buckling analyses with large deflection effect and geometric imperfections are carried out. These analyses show that the effects of non-linearity and geometric imperfections are responsible for the mismatch between theoretical and experimental results. The effect of shell thickness, radius and length variation on buckling load and buckling mode has also been studied.

A Koiter‐Newton approach for nonlinear structural analysis

“…The composition of the displacements in u and q 0 is a simple addition; however, for beams and shells where finite rotations are taken into account, the composition operation will depend on the parametrization of rotations [39]. According to Equation (2), the equilibrium equations (1) can be rewritten as…”

“…The discretized equilibrium equations of a structure can be reduced to a set of nonlinear equations of the form f.q/ D f ex (1) where f and f ex are respectively the internal force vector and the external load vector, is the load parameter, and q is the vector of DOF. The DOF q fully describes the current configuration of the structure, usually with respect to a reference configuration.…”

“…Analysis of nonlinear response of structures, especially thin‐walled structures which are buckling sensitive, is important for determining their load carrying capability under compressive loads . Researches have demonstrated that thin‐walled composite shells subjected to axial compression exhibit a high load carrying capacity and buckling which is highly imperfection sensitive.…”

Structural integrity analysis and damage assessment of a long composite wind turbine blade under extreme loading

“…This mismatch is due to the fact that linear buckling analysis is based on small deflection theory predicting higher critical load than nonlinear large-deflection buckling analysis. Further, geometric imperfections such as variation in thickness and material imperfections also reduce the theoretical buckling load as investigated in [31]. However, the linear Eigen value buckling analysis predicted the mode shape and location of buckling.…”

The reformulated Koiter–Newton method for thermal–mechanical buckling and postbuckling analysis of thin‐walled structures

“…As a consequence, the thin-walled structures may suffer an early buckling failure under the complex thermal-mechanical fields. [2][3][4] The initial stresses induced by the thermal expansion of materials may lead to an "early buckling," while the degradation of the material stiffness properties will definitely decrease the buckling load and affect the pre-and postbuckling response. 5,6 For these reasons, the geometrically nonlinear responses of thin-walled structures under the thermal-mechanical loads have received growing interests in both the research and the industry communities.…”