Help analyze web buckling strength of I-section steel

[AKAST]

I'd like to analyze web buckling strength of an I-section steel using Abaqus and compare it to a hand-calculated value



I section steel Width : 150mm , Depth=300mmm, Web thickness : 10mm, Flange thickness = 10mm / Length=300mm

Elastic modulus 206GPa, Yield strength 340 MPa, and Poisson’s ratio 0.3

Compressed by using displacement boundary condition (Not using load)

I'm trying to measure the web buckling strength, but in Abaqus, it seems to reach the material's yield strength rather than the buckling strength. This significantly differs from the hand-calculated buckling strength (301.6MPa /// Euler buckling formula & Johnson-Ostenfeld plasticity correction formula).

 

[271828]

If you are doing a nonlinear static analysis, then you would need to give the web a small initial out-of-plane displacement. As the load increases that displacement would change only a little until near the buckling load and then it would change quickly.

 

[SWComposites]

Run a linear eigenvalue buckling solution, not a static solution.

 

[FEA way]

Either use linear buckling analysis or make sure that Nlgeom is activated in general static step to perform a nonlinear buckling analysis. You will also need some imperfection. It can be introduced in the form of scaled linear buckling mode shapes. If you encounter convergence difficulties, switch to dynamic or Riks step.