> For the complete documentation index, see [llms.txt](https://tlcfem.gitbook.io/suanpan-manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tlcfem.gitbook.io/suanpan-manual/material/material3d/damage/isotropicdamage.md).

# IsotropicDamage

Independent Isotropic Damage Model

The `IsotropicDamage` model interacts with an associated 3D material model and compute damage factor based on total strain or other related quantities.

## Interface

The `update_trial_status(const vec&)` is implemented so that `trial_stress` and `trial_stiffness` store the corresponding response of the associated material model and calls the `update_damage()` method.

The `update_damage()` method shall be implemented in all derived class.

Alternatively, material state update method `update_trial_status(const vec&)` can be thoroughly overridden by the derived classed.


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