Resistance to in-plane stretching.
For a simply supported cross-ply laminate, this simplifies to ( w = 0 ) and ( \partial^2 w / \partial n^2 = 0 ) on edges. Composite Plate Bending Analysis With Matlab Code
% Define material stiffness matrix Q11 = E1 / (1 - nu12^2); Q22 = E2 / (1 - nu12^2); Q12 = nu12 * Q11; Q66 = G12; Q16 = 0; Q26 = 0; Resistance to in-plane stretching
We use a (size 2a×2b in local coordinates). Each node has 3 DOF: w, θx = ∂w/∂y, θy = -∂w/∂x. Each node has 3 DOF: w, θx = ∂w/∂y, θy = -∂w/∂x
| Tool | Best For | Complexity | Cost | | :--- | :--- | :--- | :--- | | | Learning, academic research, small parametric studies | Medium | License cost | | Python with FEniCS / scikit-fem | Open-source, similar transparency | Higher | Free | | ANSYS / Abaqus UMAT | Industrial design, large models, nonlinearity | Very High | Expensive | | LAP (Laminate Analysis Program) | Quick laminate property calc (no FEA) | Low | Free / Shareware |