connection 3D steel bar to a solid concrete block

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wael.alawsey
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Joined: Fri Feb 17, 2023 7:25 pm
Location: Hungary, Budapest

connection 3D steel bar to a solid concrete block

Post by wael.alawsey »

Hello everybody,
Can anyone please explain how to model the contact between solid concrete and a 3D reinforced bar, not a 1D line?
I think (interface material) will be the solution, but i don't know how to apply it; when I go to the interface material and select (CC3DInterface) and assign it to a bar's volume, an error msg appears when i try to run the simulation saying that (material "CC3D Interface" is not permitted for element type: line, triangle, quad, tetrahedron, point).
Also, I want to ask how to apply torque force from the nut connected in that same bar to the steel plate. You can check the images in the links below.
I really appreciate any help you can provide.

https://ibb.co/NxR7rBt
https://ibb.co/Zc6SD20
https://ibb.co/hy9yvSn
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escolano
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Joined: Sun Sep 05, 1982 10:51 pm

Re: connection 3D steel bar to a solid concrete block

Post by escolano »

Sorry, but this is not the right forum to answer this question.

It depends on the problemtype used. GiD itself is not doing any simulation, it is the pre/postprocessor.
e.g. if you are calculating with the ATENA problemtype (reinforced concrete simulations), must ask its developers the kind of boundary conditions and properties to be simulated using its software.
wael.alawsey
Posts: 6
Joined: Fri Feb 17, 2023 7:25 pm
Location: Hungary, Budapest

Re: connection 3D steel bar to a solid concrete block

Post by wael.alawsey »

Thanks for the quick reply!
I am using GID to do my simulation, and it's running just fine, but there is no contact between my 3d bars and beam concrete block! that's what I need to know how to create it
thank you
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escolano
Posts: 1923
Joined: Sun Sep 05, 1982 10:51 pm

Re: connection 3D steel bar to a solid concrete block

Post by escolano »

A GiD problemtype is composed by the calculation program an some configuration files to define its data, and are created by third part companies or users, not by us.

Each problemtype define its own conditions to store the data required for the specific simulation.
GiD itself don't define any condition, material, etc., then we cannot know if it is possible to do what you want or how must be done in this problemtype.
In fact you have not said what is this problemtype: I guess that it is 'Atena', but maybe I'm wrong.

Then must follow some 'Atena' tutorial or documentation to know how to do it (obtained from his own website, not the GiD web)

I never calculated anything with Atena, but I think that for simulate 3 contacts they require to create a 'GiD contact volume' that is an special entity that links 'two similar' surfaces, to force a 1-1 relationship of its mesh nodes, and assign also some extra condition that store contact parameters. They could be other kind of contacts that do not require this 1-1 mesh relationship and simple mark with some conditions pairs of master and slave surfaces (that do not require to be 'similar').
In any case read the documentation or your problemtype to know its features.
wael.alawsey
Posts: 6
Joined: Fri Feb 17, 2023 7:25 pm
Location: Hungary, Budapest

Re: connection 3D steel bar to a solid concrete block

Post by wael.alawsey »

Dear escolano,
Thank you so much for your reply, but I think you miss understand me!
My problem type is a simple concrete beam with a 3D steel reinforcement bar, and I am modeling it using GID version 16.0.3.
I modeled everything, but I don’t have any information about the contact between the concrete beam and the 3D bar inside the beam because its looks like a floating object and I want to connect them.
For example, one of this forum members asked you about how to connect a floating surface inside a cubic rock, and you showed him a way to connect the surface to a volume, so my problem about connecting a volume to a volume! I attached my model, if you, please take a look at it and help me with some suggestions.
Thank you
Attachments
My model.gid.rar
My model
(119.94 KiB) Downloaded 322 times
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escolano
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Re: connection 3D steel bar to a solid concrete block

Post by escolano »

It is confirmed by the attached model that you are using the "Atena/Static" problemtype
Your model has some volumes of the concrete of the beam and some other volumes of the steel bars.

Geometrically the volumes of your bars are overlapped with the beams, are not intersected and there are no holes in the beam volumes.

Please ask Atena, I never calculated with this problemtype.

I guess some possibilities, depending on the available features of Atena that I unknown.

1) maybe the easier approach is to replace the volumes of the bars with simple lines of its axis, that are also overlapped. I think that Atena can deal with it, and define the reinforced bars in this way (volume elements for the concrete and overlapped line elements for the bars, not sharing the nodes of the volume)

2) other approach is to do the boolean operations to intersect the volumes of the bars with the volumes of the beams, and then could have two more possibilities
2-A) single surfaces shared by the volumes of bars and concrete, with the same displacement for its shared nodes
My model_intersected.gid.zip
(3.95 MiB) Downloaded 327 times
2-B) bars and concrete volumes each one with its own surface not shared, and the the calculation must take into account this frictional contact, and must assign some problemtype specific conditions to simulate this contact, and probably do something special with the mesh.

I have attached your model, modified to be like the 2-A) case, including a coarse mesh.
My  model_intersected_coarse_mesh.png
My model_intersected_coarse_mesh.png (64.12 KiB) Viewed 10401 times
wael.alawsey
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Joined: Fri Feb 17, 2023 7:25 pm
Location: Hungary, Budapest

Re: connection 3D steel bar to a solid concrete block

Post by wael.alawsey »

Many thanks for your time and effort in helping me modelling my problem.
So basically, I can make holes in the shape of steel bars inside the concrete beam and then use the fixed contact surface (master and slave) between the holes surfaces and bars surfaces. Is that right?
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escolano
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Re: connection 3D steel bar to a solid concrete block

Post by escolano »

No, my solution that i called '2A' do not use any kind of 'contact'.
Simply I've made that the mesh is continuous between the elements of material 'concrete' and the elements of material 'steel'. The elements are sharing the nodes (because I have created shared surfaces between the geometrical volumes, and the mesh inherit this topology)

It will act numerically like there is glue between the steel and the concrete.
The node is unique, then its main unknown that is the displacement in the FEM simulation F=K*d is the same for both parts.

For other kind of simulations that try to represent a contact with possible relative movement between the parts in contact, must read the ATENA manuals to know how must be defined.
Please ask it to ATENA developers, this forum is for GiD questions (geometry, mesh, postprocessing, customization,...), not for third part problemtype questions.
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escolano
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Re: connection 3D steel bar to a solid concrete block

Post by escolano »

I have created a video with my operations to have a geometry well connected, without overlapped volumes.
https://youtu.be/vMb_Rc2h_p0
Basically
1-I have used the boolean operation of "substract and intersect", the result is (A-B) + (A Intersection B)
2-I have re-build the missing part of the bars, creating a cylindric volume by extrusion of a surface with translation.
3-I have used another boolean operation of 'union' to merge the cylinders and the head of the bars
4-Finally I have assigned mesh sizes to the curves, surfaces and volumes of the bars, and left the rest with a general mesh size
5-Before generate the mesh, I've set 8 threads to mesh faster, and used the 'Tetgen' option for volume mesher (this generate the mesh with a Delaunay method, that usualy is fast and robust)
wael.alawsey
Posts: 6
Joined: Fri Feb 17, 2023 7:25 pm
Location: Hungary, Budapest

Re: connection 3D steel bar to a solid concrete block

Post by wael.alawsey »

Actually, there are no words to describe my gratitude for you sir !!
Thank you so much for helping me modelling my problem.
I will try to apply all your suggestions and I wish I can reach my goal very soon.
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