Including Linear Elasticity

[Aminofa70]

Dear Febio developer,

is it possible to include Linear Elasticity to febio ?

I know febio is for nonlinear elasticity but if it has linear elasticity as well, many users do not need to use any other software.

Febio is open access and complete but not having linear elasticity ?

Thanks

[SteveMaas1978]

Hi,

Thanks for your question. With FEBio we have always focused on large deformations. And since the case of linear elasticity can be achieved by using relatively small loads, we never felt a need to add direct support for linear elasticity. Or is there another reason why you would want to see support for linear elasticity in FEBio?

Thanks,

Steve

[Aminofa70]

Dear Steve,

It is simple, because I do not want to use any other software. I am sure many users would love it.

With using relatively small loads, shall we get accurate results ?

I understand the scope of your software is for nonlinear case but including this case will be interesting.
Of course maybe I am wrong but I saw the same questions on your website that means I am not the only guy who is looking for. I use Gibbon (Comodo.jl) for mesh generation and it is connected to febio. What if it supports linear elasticity, simple no other software is required. Let's say exactly linear elasticity no challenge with changing load or whatever .

Cheers

[SteveMaas1978]

In the limit of small loads/displacements, FEBio should recover the same answer as the linear elastic case.

I think the main challenge with adding a linear elastic module is that all constitutive models, boundary conditions, contacts, loads, etc. would have to be reformulated since everything in FEBio assumes large deformations. This may be a significant development effort.

That said, putting together a basic linear elastic solid mechanics solver in a plugin shouldn't be too difficult and I'd happy to look into that. Are there any particular boundary conditions or loads that you would be interested in that I should include?

[Aminofa70]

Dear Steve,

Thanks for your reply. Yes I meant a very simple code for linear elasticity. The general boundary conditions that febio has, nodal loads, surface (pressure) and applying displacements. I am not familiar with the source code and I think we only need to script the linear elastic strain energy if I am right. If we have linear case we can still use nonlinear solver. I want it for topology optimization. Please let me know what is easer at this time and I try to digest the source code and develop a plugin afterwards for all cases.

Cheers