What are the ways to perform seismic analysis of Buried pipe line? Applicable design code is ASME B31.8.

Is it possible to perform buried pipe seismic analysis using CAESAR-II?

Thanks!

FEA (Ansys or Abaqus) is better way to look Seismic impact on pipe, including ground fault,

B31.8 is looking at the strain induced stresses on the pipeline.

In a seismic event, the buried pipe will move with the soil (imagine skid piping on a truck - when the truck moves, what happens to the pipe).

All bets are off if the pipeline crosses a fault - the pipe will likely break.

Thanks limin and Richard.

In Buried model , C-II calculates soil stiffness at descrete locations and apply. If static seismic coefficient method is applied in this model to evaluate seismic stresses like above ground piping. How good this would be? Isn't correct seismic analysis for buried pipiline?

If not, is there any way for buried piping seismic analysis other than ANSYS/ABAQUS. I suppose ANSYS would be also simulating with actual soil stiffness only but at more descrete locations than C-II.

Thanks!

Yes, Buried pipe in CII model is restrained by soil springs, and if ground shaking and whole soil and pipe will shake together, you can image the situation like Richard's example.

what your project should do that depend on your project specification and engineer judagement, we normally not consider seismic on plant design,
only pipeline project (such as cross country from USA to Canada) is considered to do seismic analys for buried pipe.

only issue is ground fault cause pipe break, that is not CII can do,
you have to go FEA with specific model, Abaqus or Anasys by Mohr-Coulomb model or PSI model.



Regards,
Limin

Thanks limin.

Except fault, is it possible to do seismic analysis for burined lines in CAESAR-II? and How?

For one of my project, it has plant piping and pipe lines (runnings in Kilometers). We are applying 0.12g ground acceleration and doing static seismic for above ground piping in the plant.
However for buried pipelines in the same project, how to do seismic analysis? Here seismic specifications are same as 0.12g.
So far we are using CAESAR-II.

Regards,