Using the results for the intact laminate in Exercise 1, compute: (a) the strains ?x, ?y, γxy at the interface between laminae, (b) the stresses σx, σ_y, τ_xy on all laminae, right next to the interface, (c) the strains ?₁, ?₂, γ₆ by using the transformation equations, (d) the stresses in material coordinates σ₁, σ₂, σ₆.

Exercise 1

Consider a [0/45/-45]S laminate, subject to a load N_x = N_y = 1000 N/mm. Compute the [A], and [D] matrices (neglect shear deformations) for the intact laminate. Each lamina is 2.5 mm thick. Do not adjust for in-situ strength. The material properties are:

E₁ = 204.6 GPa

E₂ = 20.46 GPa

G₁₂ = 6.89 MPa

v₁₂ = 0.3

F_1t = 826.8 MPa

F_1c = 482.3 MPa

F_2t = F_2c = 68.9 MPa

F₆ = 241.15 MPa