Answer: Boundary Change Assignment: can be used to apply separate boundary conditions for different analysis/static load case within the same model.
Example: Even in the case where static analysis and dynamic analysis are associated with different boundary conditions, the two analyses can be carried out within the same model without having to make two different model files.
It is important to note that, we have boundary conditions applied to the model in Post CS(End of construction stages). This boundary conditions will be maintained for all further analysis unless we change them using boundary change assignment.
If we select some Boundary Type from Data Selection, then only that type gets altered and rest of the boundary types will be applied as it is in the model. So we should be careful in selecting the required boundary group list. if necessary For a Boundary Type we need to create additional boundary groups having the required boundary condition and select them and add.
Also, when we add certain boundary group from "Boundary Group List" then only that will be activated and rest of the boundary groups of the Boundary Group List will be deactivated automatically.
Procedure:
1. Data SelectionIn data selection, choose the type of boundary condition, which can be applied to different load case/analysis from the list.
2. Boundary Group CombinationBoundary Groups of the type selected are listed to choose. When we choose certain boundary group and add.
3. Select the Boundary Group Combination for the required analysis/static Load case.
See below screenshot, to change boundary condition for Moving load analysis from Existing supports to Proposed supports.