Designing for Torsion
Designing for Torsion
(OP)
I would like to check the torsional resistance of an I beam supporting steel joists. Originally both sides of the beam had joists - the joists meeting at the beam. The current client wants to make an openinng in one bay, leaving the loading eccentric - on one side of the beam. Any ideas on how to assess the beam's resistance under combined bending and torsion.






RE: Designing for Torsion
Design Guide 9:
Torsional Analysis of Structural Steel Members
An expert is a man who has made all the mistakes which can be made in a very narrow field
RE: Designing for Torsion
RE: Designing for Torsion
Re your second case; if the beam twists there is torsion in the beam.
Unless the extent of twist is limited by something other than the beam itself (eg moment connection of joist to beam) there is the possibility that the torsion is significant and must be checked.
It shouldn't be too difficult to ensure that the beam twist is limited by the joists, depending on the configuration of the connection.
ckpeng
If you're a Brit use the SCI's 'Design of Members Subject to Combined Bending and Torsion'.
If you're a Skip I believe Trahair published something in the ASI (then AISC) journal.
RE: Designing for Torsion
DaveAtkins
RE: Designing for Torsion
BA