Modal Prestressed

Prestressed eigenvalue analysis is governed by:(1)

$$\left(\overline{\text{K}}\text{+}\text{λM}\right)\text{A}\text{=}\text{0}$$

Where,

$\overline{\text{K}}$

Prestress stiffness matrix

$\text{M}$

Mass matrix

$\text{A}$

Eigenvector

$\text{λ}$

Eigenvalues

Depending on preloading conditions, the resulting effect could be a weakened or stiffened structure.

• If the preloading is compressive, it typically has a weakening effect on the structure (for example, column or pillar under compressive preloading).
• If the preloading is tensile, it typically has a stiffening effect (for example, rotorcraft blade under centrifugal preloading).