Javgarloz,

My understanding on this...
First you need to classify whether you are going to treat SAM as causing fatigue (secondary stress) or SAM causing primary stress failure. Then you can develop your load cases...

The codes are not very specific on the usage of SAM. The interpretation 20-45 states - "shall externally imposed displacement strains, excluding single cycle events, be considered in conjunction with thermal displacement
strains? " and the answer is Yes.
What is this "excluding single cycle events"....???
How can you count cycles during an earthquake event....and how many cycles exists...??
There is a possibility that the SAM is a single cycle and be treated in primary stress ---- occasional stress.
Hence treatment of SAM in B31E, is to use SAM along with inertia stress and check with allowables (equivalent to that from ASME Sec.III Sub.NC-upset condition). The allowable are not 1.33 Sh, but higher.
PD/4t + 0.75i(Msus + Mseismic)/Z < min(2.4Sh;1.5Sy;60ksi)

If SAM is treated as occasional, then combination with thermal is not required. i.e (T1+D1+D4+D5+D6 < SA)

ASME Sec.III codes treat SAM as causing fatigue failure and the allowable are....."3SA"
Hence do not mix codes...either use B31.3 and B31E
Or use ASME Sec.III

Mentors do advice....

Regards,
Suraj