Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

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

Concrete hight depth long beams flexural-torsional instability...

Status
Not open for further replies.

ugoveri

Structural
Feb 6, 2003
13
I need help on the following...

For steel beams,the flexural-torsional instability is taken in consideration by the form of lambda= (My/Mcr)^.5 being My the yelding moment and Mcr the Elastical Critical moment, with which we can obtain a reduction factor for the final plastic or elastic resistance due to lateral-torsional instability.

If I have a concrete beam lets say, with 4.5m high and 30 meters long with only 30cm thick, which isn't braced in the mid span, how can I check if I have instability for flexural torsional mode?

I mean, the resistance of the beam is huge if it doesn't buckle, but if it does? How can I have it in consideration?

Ok, I can get the critical elastic moment, but how to use that information to get a reduction of plastic resistance?

I would prefer some guidance based on the eurocode, but some other code recomendation will work to if it's not a blackbox information...

thanks in advance
 
Replies continue below

Recommended for you

ACI in the US puts the maximum ratio of span to beam width at 50.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor