The free edge effect is an inter-galactic phenomenon found on the outer reaches of the cosmos that leads to a parallel…well…no, not exactly. What I’m referring to is a region within a laminate that produces a fully three-dimensional stress field at the free edge, then decays quite rapidly to a two-dimensional stress field as the distance from the free edge increases. The three-dimensional stress field is responsible for delamination at a free edge, and is commonly referred to as inter-laminar stresses. A composite analysis is typically confined to classical lamination theory. Unfortunately, this assumes that all out-of-plane stresses are zero, making the determination of transverse stresses impossible. Consequently, this assumption is not valid when one is interested in calculating out-of-plane stresses in regions near or at a free edge.

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### Quasi-Isotropy | Wait...what is that?

### Quasi-Isotropy…wait…what is that?

What is it you ask…well, this is one of my favorite meals. A large quasi-isotropy with a side of fries and coke. LOL…but of course is isn’t…actually, this is a laminate that when constructed correctly emulates a metallic material that follows the isotropic relationship defined as: E_{x}= E_{y} = E_{θ. }Quantitatively this can be described using a *general **rule **for a **quasi-isotropic** layup. Simply **apply the following equation** that defines the angle between the plies for a symmetric laminate having an identical number of plies at each orientation**:*

**Equation: π/n → n≥3**