Topic: Steel detail

Good morning,
I am currently trying to simulate the behavior of a detail of connection of steel element to reinforced concrete block. I obtained a reasonable shape of load-displacement curve. The problem is that when I look at the stresses calculated in steel element, the values are unrealistic. The yield strength of the steel used is 235 MPa, but I receive stresses higher than 1000 MPa in relatively big areas.
My question is whether it is possible in ATENA to somehow specify ultimate strength of steel material and to predict failure (tearing, cracking) of steel elements.

Another question - does ATENA allow to simulate buckling and post-buckling behavior of steel elements?

Thank you for your help

Petr Bily

Re: Steel detail

Good afternoon,
I assume you refer to volume elements with the 3D Bilinear Steel Von Mises material.

First, please see ATENA Troubleshooting, 2.1.23 The tensile (or compressive) stresses exceed the tensile (or compressive) strength or yield stress – what is wrong?

If that does not explain what you see, make sure to define your material without hardening (i.e., ideal plastic).

In the current ATENA version, only a bilinear material model is available for modelling 3D steel elements. A multilinear material model with ultimate strain is planned for a future version.

With respect to buckling, yes, this is automatically included in the analysis by considering nonlinear geometry (as long as the switch "geometrically nonlinear" is enabled or the load step is reasonably short).