## 5.6. Nomenclature

### Greek Symbols

α | Coefficient of thermal expansion / Fracture angle in LaRC
β | Coefficient of moisture expansion / Shearing angle in draping
γ | Shear strain, shear angle
η | Coefficient of influence
Δ | Load change
ε | Normal strain
ϑ | Third coordinate of the modified cylindrical coordinate system
κ | Curvature
ν | Poisson's ratio
σ | Normal stress
τ | Shear stress
φ | Misalignment angle
ϕ | Second coordinate of the cylindrical coordinate system
ξ, η, ζ | Principal stress/strain coordinate system

### Latin Symbols

| Curve fitting parameter for Cuntze's failure criterion
| Components of the 3-D stiffness matrix
| Young's modulus
| Coefficients in quadratic failure criteria, stress space
| Interaction coefficient in the Tsai-Wu criterion
| Failure criterion function
| Shear modulus
| Toughness ratio
| Moisture / humidity
| Thickness
IRF | Inverse Reserve Factor
MoS | Margin of safety
| Interaction exponent for Cuntze's failure criterion
| Slope parameter for Puck's action plane criterion
| Shear failure stress in the 23-plane/Wrinkling coefficient
| Shear failure stress in the 13-plane/Midplane curvature radius
| Fracture resistance in Puck's action plane criterion
| Radial ordinate R+z
rd | Radius difference
RF | Reserve Factor
| Shear failure stress/strain in the 12-plane
| Temperature
| In-plane displacement in x, y-direction
| Failure stress/strain for isotropic material
| Through-the-thickness displacement
| Failure stress/strain in the 1-direction
| Global x-coordinate
| Failure stress/strain in the 2-direction
| Global y- and longitudinal coordinate of the cylindrical coordinate system
| Thickness coordinate
1, 2, 3 | Ply principal coordinate system

### Subscripts

| Core
| Compressive
| Delamination
| Exposure
| Effective
| Face sheet
| Bottom face sheet
| Top face sheet
| Fiber failure mode
| In-situ
| Matrix failure mode
| Supporting point number
| Tensile
| Perpendicular to fiber
| Parallel to fiber
| Wrinkling
, | Derivative

### Superscripts

| Midplane strain
| Action plane
| Under compression load
| Sum of temperature and moisture effects
| Longitudinal
| In misalignment frame coordinate system
| Under tension load / Transverse

### Acronyms

FF | Fiber Failure
IFF | Inter-fiber Failure
INS | Interlaminar Normal Stress
ISS | Interlaminar Shear Stress
LSoE | Linear System of Equations
UD | Unidirectional

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