Changing common parameters in rebar

[boluzhitsevda]

Hi everyone!

I came across a situation where common parameters of rebar segments change places with each other after adding coupler at one end of the rebar.

Below on the first screen is the situation before adding coupler:

Below on the second screen is the situation after adding coupler:

As you can see the parameters have swapped places.

Has anyone encountered such a situation when using couplers in rebar?

Can anyone tell me constructively about the mechanics of working common parameters and their dependencies on couplers in such situation? Why does this happen?

[jay_colc]

I can only think that when the element was placed the C leg was referenced or drawn first so took priority when reporting but when the coupler was added Revit regenerates the shape and then places the list in alphabetical order?

it is but a thought!

[ovidiu_paunescu]

Hi @boluzhitsevda 

You probably have the end treatment included in the rebar shape definition (Structure tab > Reinforcement panel > Reinforcement settings).

This means that Revit flips the start and end of a symmetrical shape to match a shape that exists in your project already. It's a similar behavior for hooks.

[boluzhitsevda]

Hi @ovidiu_paunescu 

I checked this setting and this checkbox isn't active. 

"This means that Revit flips the start and end of a symmetrical shape to match a shape that exists in your project already. It's a similar behavior for hooks." - Can it works without "end treatment included" setting?

[ovidiu_paunescu]

Yes, the flip still happens, even if the shape is the same. I think the original idea was to not have identical bars (same rebar number) but with different end treatments at start and end.

[boluzhitsevda]

@ovidiu_paunescu first of all i  wanna thank you for your supporting information.

“I think the original idea was to not have identical bars (same rebar number)” - You mean “rebar number” which is the system parameter for rebar, yes? If so, it looks like very specific idea to use this parameter in this direction.

But this may be connected somehow further with some of the design process. @ovidiu_paunescu   Do you know anyone who knows, for what purposes was it so implemented?

I've tested your theory. Indeed, the rebar number changes after the coupler is added to the rebar on one of the ends. But with a nuance.

On the screen below rebar before adding coupler and rebar number is 118:

 

On the screen below the rebar number has changed on 289 after adding coupler:

 

On the screen below the rebar number has not changed and still on 289 after adding second coupler and this is a little nuance:

 

We need to know these nuances of the mechanics of the rebar in order to take into account our moments when preparing design documentation.

Because we are developing very specific and unique structures like this:

 

We also have questions about ring rebar and we would like to get support on this theme too.

[ovidiu_paunescu]

Hi @boluzhitsevda 

The way numbering works is by comparing the values of A, B, C.. parameters for bars that have the same shape and are in the same partition.

The start/end flip of the rebar shape happens, so that two bars with the same shape and A, B, C values (and same rebar number) will have the ET on the same end.

For example, if you add a coupler to a bar with shape M_17 and B=300, C=400, D = 500, at the start, then for an identical bar you add a coupler on the end, that second bar is flipped, start becomes end, and B=500, C=400, D=300. So it gets a new number. If it didn't and you would show these bars in a schedule, the ET would show varies, because for one bar it's at the end, for another it's at the start.

If the ET would be included in the shape, a new shape would be created and would get a different number

When you are adding the second coupler, the bar is not flipped, so the number doesn't change.

Here are some links to my AU classes. You will find information about how rebar works, some of its nuances, and some tips and tricks for working with rebar in Revit. You can review these in this order:

• Rebar Modeling in Revit: Keep It in Check | Autodesk University
• Tips and Tricks for Effective Rebar Detailing in Revit | Autodesk University
• Revit for Rebar: Why BIM Is Better for Concrete (BES500050)
• How to Make the Most of Rebar Detailing using Revit | Autodesk University

[boluzhitsevda]

@ovidiu_paunescu thank you for such a detailed answer and for such informative support.

Also thanks for links with educational material.

I will be studying this for the next few days.