• Registered: 2010-09-29
  • Posts: 2

Topic: Eligehausen local bond stress-slip model

Someone used the local bond stress-slip model proposed by Eligehausen in 1983 to simulate the behaviour of ribbed bars under cyclic actions?
What is the best way to introduce this model in ATENA instead of using Bigaj's or CEB bond-slip model?

Thanks a lot,

Ana

Quote Post 1

  • dpryl
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  • Registered: 2007-07-13
  • Posts: 1,107

Re: Eligehausen local bond stress-slip model

I am afraid this bond model is not implemented in the ATENA kernel and adding it is not planned in close future.

The only way I see is to modify the bond function (multilinear slip - stress law) during the analysis.
However, this means editing the ATENA .inp file manually, and basically you just define a new bond function after some load step, i.e., you can not directly use the material point history etc. to calculate the new function. I think this should work quite well if you have a single bar or so, however, having many bars with bond functions changing at various times would definitely mean a lot of work - I would recommend finding some reasonable simplification in such case.

dpryl's Website

Quote Post 2

  • Registered: 2010-09-29
  • Posts: 2

Re: Eligehausen local bond stress-slip model

Thanks a lot for our suggestion.

In fact my goal is to simulate the behavior of specimens of concrete with a single reinforment bar subject to reversead cyclic actions.

When you refer "editing the ATENA .inp file" you mean introduce other "bond material" with different bond stress -slip values or a user defined bond law similar to the ones already in ATENA like the ones proposed by the CEB and Bigaj?

Sorry for all this questions but this is my first experience with Atena...

Ana

Quote Post 3

  • dpryl
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  • Registered: 2007-07-13
  • Posts: 1,107

Re: Eligehausen local bond stress-slip model

A little background:
The CEB and Bigaj bond models in ATENA are in fact generators of multilinear stress-slip laws, which are then used by the ATENA kernel.

I would suggest the following workflow:
1. generate the initial bond law using one of the models in ATENA (or one that is close to it)
2. export the .inp file from the GUE (Data - Save INP files - Together in ATENA 3D or ATENA - Create .inp only in GiD; in ATENA 2D, you have to activate the "Enable input file editting before starting FE analysis" function and check the "Edit ATENA analysis input file" box and then copy the contents of the edit window)
3. open the file in an editor (Notepad is enough), find the bond law function (modify it if the exact one could not be generated), copy it before the step when it should change, and edit the copy
4. run the analysis from the .inp file (in ATENA 3D, File - Open other - Analysis control file, or using AtenaWin or AtenaConsole)

And, of course, we are prepared to help you.

dpryl's Website

Quote Post 4