Good morning,
Is it correct to consider the seismic aceleration on the underground pipe analysis?
I'm performing a stress analysis on a 54" underground pipe full of liquid.
The seismic aceleration in the Project is g's = 0.285
And of course the forces due to the seismic factor are very high compared to the normal operating forces.

Thanks.

The project acceleration is probably based on a the swaying of a typical structural member, and thus would probably be overly conservative for buried piping.

It would not be incorrect to include a seismic case for buried piping, you probably don't have the correct data to do so accurately.