Hii everyone,
We are using CAESAR II version 16 to analyse a piping system in which displacements for associated cases are imported from connected reference system (Analysed separately)
The reference line is mounted in spring and the spring is pulled slightly in sustained case.
Now my queries is do we need to add any displacement in alternate sustained case for proper simulation of the system???

Regards
Shrikant

It may be necessary to include a displacement set as part of your Alt-SUS case. The bigger question is what are those numbers?
Since you separated your system into segments, an evaluation of a single segment requires the proper boundary conditions to mimic the missing segments. Assuming that the deadweight of your segment will not alter the deadweight position of the missing segments, you may be able to use the deadweight position of the missing segments as your boundary condition for the Alt-SUS evaluation of your segment.
Needless to say, breaking systems requires the user to get involved in maintaining equilibrium across these artificial boundaries.