I was wondering if modeling and analyzing both piping and structural framings would lead to much different results compared to those gained via piping analyzed solely, mainly when some 3mm gaps are considered for line stops which could be filled with structure movements/deflections. This would be worsened in seismic events.
Hence, to be short, why in most cases framings are not analyzed with piping systems?

PS my company is going to use axial gapped restraints instead of shock arrestors and I disagree;
My reason: ASME B31E does not allow using axial gapped resraints and just lateral gapped restraints can be used considering an impact factor of 2.
Company reason:"Structure will deflect in reality' and thus adds 15mm to OPE displacement as the gap.

Would you please send ur comments re this?