Balanced and Symmetric Laminates with Bending-Twisting Coupling
Description
Balanced and Symmetric Quasi-Isotropic Laminates - Electronic annex to an article on Compression and Shear Buckling Performance of Finite Length Plates with Bending-Twisting Coupling: This electronic annex provides an extract from the laminate database described below, for quasi-isotropic designs only, in which all designs share a single point, or coordinate (0,0), in the lamination parameter design space for extensional stiffness. Quasi-isotropic designs are often used for benchmarking purposes due to the simplification of the in-plane properties, but this simplification should never be assumed to extend to bending stiffness properties. For the symmetric stacking sequences considered in the associated article, quasi-isotropic properties are found exclusively within 8 and 16 ply laminates, for which there are 6 and 536 solutions, respectively. The stacking sequence listings for 16 ply laminates are presented together with their lamination parameter coordinates. They are grouped by matching orthotropic bending stiffness to reveal the significant differences in Bending-Twisting coupling magnitude, where each grouping contains between 2 and 6 stacking sequences. Balanced and Symmetric Laminate Design Data - 10% Rule - Max Ply Contiguity 3 This spreadsheet contains the complete database of balanced and symmetric designs, with Bending-Twisting coupling, to which the 10% rule has been applied, i.e., the minimum number of plies in each of the standard ply orientations. Ply contiguity constraints have also been applied, which limit the maximum number of adjacent plies with the same orientation to 3, as is now common design practice. For the meaning of the symbolic stacking sequence notation used, the reader is referred to the electronic annex described above.