A SOLUTION OF LAMINATED CYLINDRICAL-SHELLS 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 piece-wise nature of the displacements. The zero-shearing condition on the laminate surfac es and continuous conditions for the transverse shear stresses on the inter-laminar surfaces have been considered for the final stresses cal culation, the displacement functions remain to be unconstrained. This theory is very useful for the finite element analysis because it reque sts only C-0 continuity for the assumed displacement fields. By compar ing with three-dimensional elasticity theory for laminated orthotropic cylindrical shell, the performance of the present theory is verified. The problems solved in this paper illustrate that the present theory is very accurate for the thin and moderately thick shells.