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Section 8.10: Limitations of FEBio Up Section 8.10: Limitations of FEBio Subsection 8.10.2: Material instabilities

### 8.10.1 Geometrical instabilities

A geometrical instability is a point in the solution at which several paths for continuing the solution are possible. Typical examples are buckling of a column. FEBio's Newton based solvers cannot handle buckling since usually at these points, the material's elasticity tangent is not uniquely defined. Although in some cases FEBio will be able to pass a buckling point, in most cases, FEBio will not be able to converge to a solution.
Section 8.10: Limitations of FEBio Up Section 8.10: Limitations of FEBio Subsection 8.10.2: Material instabilities