Question:
In the case of the "Initial strain from other LC/CO" feature, I cannot retrace internal forces. How is this function mapped internally?
Answer:
The function transfers the deformation from one LC or CO into another LC or CO. Internal forces and stress states are not transferred at the same time.
If the load case or the load combination is based on the same structural system, no significant internal forces should result. The FE division in the structure could have an influence here, and should be checked, if necessary.
If the initial strain is transferred into a load case or a load combination that is based on another structural system, additional internal forces may result due to the prevented deformation (restraint). In the example (Image 02), the initial strain of two consecutive single-span beams is transferred to a continuous beam. The deformation on the intermediate column is prevented and a moment is generated (Image 03). The magnitude of the resulting moment can be better illustrated by cutting free the structure and applying the prevented deformation as an imposed deformation on the load side.