Int. J. Mech. Sci. Vol.34, No. 9, pp, 727-742, 1992 0020-7403/92 S5.00 + .00 Printed in Great Britain. © 1992Pergamon Press Ltd ELASTOPLASTIC BUCKLING OF AXIALLY COMPRESSED CIRCULAR CYLINDRICAL SHELLS E. ORE* and D. DURBAN Faculty of Aerospace Engineering, Technion, Haifa 32000, Israel (Received 2 January 1992) Abstract--Buckling of axially compressed circular cylindrical shells is examined within the framework of small strain elastoplasticity. A linear bifurcation model is used along with the J2 flow and deformation theories. All four possibilities of simple supports (SS1-SS4) and clamped edges (CL1-CL4) are considered. A general solution is given with special emphasis on the axially symmetric modes. Numerical results show that the weakening effect of the relaxed simple supports (SSI-SS2) is considerably reduced in the plastic range. A detailed comparison with available experirriental data points in favour of the deformation theory. NOTATION A, Ai i = 1,..., 6 ~ integration constants B,C,C i i=1, ..,4 ) a i,b i i=1 ..... 4 defined inEqns(56) E elastic modulus E o = E/(1 - v 2) E s ~ecant modulus Er tangent modulus E xx, E xo, Eoo instantaneous moduli G shear modulus Gs defined in Eqn (13) G T defined in Eqn (9) Gxo instantaneous shear modulus g defined in Eqn (2) H s defined in Eqn (16) H~ defined in Eqn (11) h shell thickness K material parameter, Eqn (36) k axial wave number L shell length l = L/2R M , Mxo, M o moment resultants m circumferential wave number N~, Nxo, N o stress resultants Nxo prebuckling axial stress resultant n power law exponent, Eqn (36) P defined in Eqn (49) p, p~ i = 1 .... ,6 characteristic roots Qt, Q2 defined in Eqns (52) ql i= 1,2 defined inEqn(27) R shell radius S~j stress deviator u, v, w velocities, eigenmodes x axial coordinate z normal coordinate F defined in Eqn (50) 6~j Kronecker's delta total strain eij strain tensor ex, e ~o, e o strain components ) This paper is based on a part of a thesis submitted to the Technion, in partial fulfillment of the requirements for the degree of Doctor of Science. 727