column modelling

[shreoshri]

Hi everybody,
I am starting to model a column that is braced against sideways. But I am finding it difficult to get the proper way. Can you please show me the way to model a column whose one end is fixed and other end is pinned.

Shreoshri Kashyap
Tezpur University

[seismosoft]

You can use end releases for all the bending moment at one end of the columns (see Element Connectivity module)
Seismosoft Support

[Fehrmax]

Dear SeismoStruct

I am modelling an existing concrete-steel-hybrid building with SeismoStruct. For the lateral resisting only the RC walls and cores are relevant and all the columns should be hinged connections at both ends. I tried using the moment release setting, but then an unknown error comes up every time I try to do the eigenvalue analysis. Even when I try to get around the error manually by adding nodes and linking them with equal DOF (x+y+z) to create a hinge the error comes.... Do you have any idea what the problem could be?

[z.gronti]

Dear Fehrmax,

Could you please send me more information and your model to check it to z.gronti@seismosoft.com?

[z.gronti]

Dear Fehrmax,

The error message you refer is just a warning message about "Zero diagonal terms encountered in a give node".
As it is written in SeismoStruct's User Manual: "This means that such node is unrestrained in the degrees-of-freedom indicated (i.e. the node is not connected to an element or constraint capable of providing any restrain/stiffness in such dofs), a condition that, if unintended, implies the presence of an error in the assemblage of model. If, instead, such unrestrained nodal dofs have been intentionally introduced, the user may proceed with the analysis, knowing however that numerical convergence difficulties may arise more easily in such cases.".