Feature - Thermal and Imposed strain in bar elements

[epsi1on]

Discussed in https://github.com/BriefFiniteElementNet/BriefFiniteElement.Net/discussions/185

^{Originally posted by **jose-ortolano** June 21, 2024} Hi! I'm doing some tests with Brief Finite Element.NET. I am trying to figure out if it is possible somehow to impose a strain in some bars. My main goal is simulating the effect of loads such as temperature or prestressing. Any information or help will be appreciated. Thank you in advance! Kind Regards,

there are two cases:

• where an element got thermal diff and expands (thermal expansion coefficient),
• where an element have initial strain, like length error.

Probably both can be implemented as new load(s), which inherits from ElementalLoad.

[epsi1on]

imposed strain can be implemented as new load, which inherits from ElementalLoad. the load only have to affect truss behavior of BarElement, and membrane behaviour of TriangleElement. TetraHedron have no behavior but also affected. the thermal load better to be not there directly as there will be another property like Material.TEC (Thermal Expansion Coeeficient) on the Material class and a new property of Element.TD (Thermal Diff) for element. So there will be only one class for Imposed strain which get's the strain amount from user.