Influence of residual stresses and geometric imperfections on the elastoplastic collapse of cylindrical tubes under external pressure
|Author(s)||Le Grognec Philippe1, Casari Pascal2, Choqueuse Dominique3|
|Affiliation(s)||1 : Ecole Mines Douai, Polymers & Composites Technol & Mech Engn Dept, F-59508 Douai, France.
2 : Inst Univ Technol St Nazaire, GeM, Lab Civil & Mech Engn, F-44606 St Nazaire, France.
3 : IFREMER, Dept Mat & Struct, F-29280 Plouzane, France.
|Source||Marine Structures (0951-8339) (Elsevier), 2009-10 , Vol. 22 , N. 4 , P. 836-854|
|WOS© Times Cited||10|
|Keyword(s)||Cylindrical containers under external pressure, Residual stresses, Imperfection sensitivity, Elastoplasticity, Buckling|
|Abstract||The buckling problem of a circular cylindrical shell has long been widely investigated due to its great importance in the design of aerospace and marine structures. Geometric imperfections and residual stresses are inevitable in practice and have been so far frequently considered in analytical and numerical predictions. But little attention has been paid until now on the combined influence of such initial defects on the critical and often unstable response of such elastoplastic structures. In this paper, a shell finite element is designed within the total Lagrangian formulation framework to deal with the elastoplastic buckling and post-buckling of thin cylindrical tubes under external pressure and axial compression. A specific experimental process will be introduced in order to measure residual stresses in the shell very accurately, so as to include them in the numerical calculations. The present formulation will enable us to describe the complete non-linear solutions, namely the critical pressures (bifurcation and limit (collapse) loads), the bifurcation modes and the bifurcated equilibrium branches up to advanced post-critical states. Comparisons will be made between numerical results and the experimental critical value and deformation patterns of a new generation profiler. Furthermore, the combined effects of geometric imperfections, residual stresses and plasticity will be analyzed. (C) 2009 Elsevier Ltd. All rights reserved.|