SOLUTION OF A LAMINATED CYLINDRICAL-SHELL USING AN UNCONSTRAINED 3RD-ORDER THEORY

An unconstrained third-order shear deformation theory is presented for the analysis of laminated anisotropic cylindrical shells. Based on th e realistic through-thickness distribution of the in-plane displacemen ts, a zig-zag function is used to approximate the piecewise nature of the displacements. The zero-shearing condition on the laminate surface s and continuous conditions for the transverse shear stresses on the i nter-laminar surfaces have been considered for the final stresses calc ulation, while the displacement functions remain to be unconstrained. This theory is very useful for finite element analysis because it requ ests only C degrees continuity for the assumed displacement field. By comparison with three-dimensional elasticity theory for laminated orth otropic cylindrical shells, the performance of the present theory is v erified. The problems solved in this paper illustrate that the present theory is very accurate for thin and moderately thick shells. (C) 199 8 Elsevier Science Ltd. All rights reserved.