Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Seismic deflection of tall towers

Status
Not open for further replies.

Bobfromoh

Mechanical
Sep 9, 2002
157
US
I have a tall tower and seismic controls. Someone wanted to know what the maximum deflection was. As it turns out, the software I use gives me the wind deflection but not the seismic deflection. I'm sure it's due to the seismic calc being complicated. But I was wondering if there was someway to get an approximation of the deflection?

 
Replies continue below

Recommended for you

Not unusual to not calculate seismic deflection. Would tht be a quasi-static or dynamic deflection?

Deflection of towers is a concern from a process perspective as the liquid sloshing around on the trays can cause the distillation to not work as intended. Most folks, however, agree that a 1 minute seismic event over the life of the vessel will not substantially impact product quality.

Wind events can be far more frequent and so deflection is a bit more commonly a concern.

I'd ask why seismic deflection is an issue... See if you get a process argument or a P-Delta argument.

jt
 
The formula for the deflexion is the same as a cantilevered beam use the developemented Moment in the first or 3rd mode


JustoleJim
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top