Lateral torsional buckling?
Lateral torsional buckling?
(OP)
I want to calculate Lateral Torsional Buckling capacity moment on ordinary beam with arbitrary section. I don't how to (in SAP):
1) Choose the material (linear, nonlinear...)
2) I think that I must model a beam with Final Elements
2) Apply the loads
3) Apply the supports
4) Which analyse to run
5) How to read the results
Can you help with these basic questions (is there any example).
1) Choose the material (linear, nonlinear...)
2) I think that I must model a beam with Final Elements
2) Apply the loads
3) Apply the supports
4) Which analyse to run
5) How to read the results
Can you help with these basic questions (is there any example).
Drile007





RE: Lateral torsional buckling?
Buckling factor of 5, for example, means that the load could increase up to 5 times before causing the system to lose stiffness by buckling. You can run the buckling with frame/beam or finite element models.. assuming you meant to say finite elements instead of Final elements
RE: Lateral torsional buckling?
Keep in mind that your answers will be purely elastic. In other words, the stress you're getting is the equivalent of Fcr from AISC 2005 Eq. 2-4 for example, NOT a buckling stress or load that accounts for inelastic buckling. If the stress is high enough, you have to figure out a way to adjust for inelastic buckling and Spec. equations usually provide a fairly easy way to do this.
If you have a system without a trivial solution, your only option is to do a nonlinear static analysis, or a series of them, to determine the buckling load.
RE: Lateral torsional buckling?
Thank you 271828,
but you are talking abaut the second step-> how to play with results, but I need information how to "build" correct model (which elements, material, analysis, etc. should I use(run)). Can you recommend me this basic info.
Drile007
RE: Lateral torsional buckling?
RE: Lateral torsional buckling?
Curently I don't have exact problem, but one day I was wondering about the ∧ and ∨ beam shape. I was thinking about I beam with large openings too...
Thanx 271828 for your attention!
Drile007
RE: Lateral torsional buckling?
The key to doing anything like this is to start simple and work your way up, verifying that it is doing what you want at each little step. For example, you can probably find the LTB solution for a rectangle. Then figure out the LTB for an I-shape.