Modelling steel connections behaviour - link elements

[Ana Santos]

Hi Seismosoft,

I'm modelling a steel MRF frame , with steel connections with friction dampers in SeismoStruct. The behaviour of the connection is characterized by a hysteric behaviour and I am trying to introducing it on the model by means of link elements. However, I am not sure about the type of curve that is better to use to best fit the connection behaviour and I have some doubts about the parameters that the program request as well. Can you help me?

[z.gronti]

Dear Santos,

The Modified Richard-Abbott curve - rich_abb will fit the connection behaviour you are looking for. You may refer to the Help System, User Manual and to the proposed literature for more information about the aforementioned link element.

Also, in the Verification Report you will find an example "Chapter4-EXAMPLE 2 – Steel joints" where the Modified Richard-Abbott link element is used.

[Ana Santos]

Dear Zoi Gronti,

Thank you very much for your help. All the empirical parameters are determined by experimental analysis?

[Ana Santos]

Dear Zoi Gronti,

I was looking for the article written by Dela Corte et al (200) " Influence of connection modelling on seismic response of moment resisting steel frames" for a better understanding of the Modified Richard-Abbott curve, but I can not finding it. Is it possible for you to upload the article here so I can download it?

[z.gronti]

Dear Santos,

You should refer to the corresponding literature for the empirical values.

Unfortunately i don't have the requested paper.

[Ana Santos]

Dear Zoi gronti,

Thank you very much for your help.

I use a inelastic frame based element with 5 different integration sections for the beam of the frame. When I define the link elements for modulate the behaviour of the beam-to-column connection I have to insert elements links in each of integration sections ? Or this integration sections are not the same as discretized the beam into 5 different sections ?

[ruipinho]

Ana, hi.

In order to model steel beam-column connections, link elements need to obviously be introduced at the intersections between the beams and the columns, that is, at the end nodes. (in other words, the number of intergration sections has no bearings on this issue)

Rui

[Ana Santos]

Rui , Hi

Thank you for your help.
To take into account the nonlinearity of the elements beam and columns when I should use inelastic force-based frame or inelastic displacement based frame elements? I have read the bibliography about it but I am not certain when I should use one or another.

Ana

[ruipinho]

Dear Ana,

This latest question of yours is not related to connections and link elements, hence you should initiate a new discussion thread, if you really wish to pursue this topic (in any case, the short answer is: force-based elements are the best option in the majority of cases).

Best,

Rui