seismic load legs vertical vessel

[Ehiman1]

Good morning to everyone,
When you calculate sesmic force on vertical pressure vessel with 2 legs, you use Seismic force only in 1 direction or:
100%Seismic force in one direction and 30% in hortogonal direction to check legs plate?

Thank you

 

[KevinNZ]

The 30% rule is from Civil design and you will not find this the pressure vessel codes. Are you designing the vessel to leg attachment (pressure vessel rules) or the support and foundation (Civl design rules). There are also different EQ reactions/loads depending which rules you are using. ASME codes are working stress design and Civil design is usually strength design.

 

[r6155]

Only 2 legs?
Can you send us some drawing?

Regards
r6155

 

[Ehiman1]

Good morning to everyone,
I am sorry but I can't attach drawings.
About the problem I have other two questions.

The horizontal seismic force has to applicate to the c.o.g. of the vessel or at 2/3 of Height of the vessel?
In the pressure vessel design manual I see sometimes they use c.o.g. and other ones they use 2/3*H.
And About to consider the 30% of seismic force in the other direction to check legs where I can see in the normative that this component is negligible?