Modelling of I-beam...
 
Notifications
Clear all

Modelling of I-beam in a column  

 

saberman12
(@saberman12)
Junior Member
Joined: 1 year ago
Posts: 20
February 14, 2020 9:01 am  

Hi, I am trying to model a I-beam reinforcement in my column. I learnt that there are a total of 3 methods of doing that. Model the I-beam with solid element, shell element or beam element.

Solid element is certainly the most straightforward. However, I am trying to model the I-beam with shell or beam element which is the problem I am currently facing. For shell element, I have no idea how to do it. For beam element, using Integration_Beam and Section_Beam, I am able to change the shape of my rebar to an I-beam but the size of the I-beam does not change when I changed the dimensions.

I hope you are able to help me. Thank you.


Quote
Negative Volume
(@negativevolume)
Senior Member Admin
Joined: 2 years ago
Posts: 344
February 16, 2020 4:03 pm  

@saberman12
I’m not sure how sophisticated LS-Dyna’s beam integrations are regarding this. When you say that the size is not changing, do you mean visually? Or is there no way to change the cross sectional area in the section card?

Using shells should be similar to implement as solids but even easier. You just want to mesh with quads and make sure that everything is node to node connected and that your mesh is clean, meaning that you have single lines of nodes lining the length of the I beam.


ReplyQuote
saberman12
(@saberman12)
Junior Member
Joined: 1 year ago
Posts: 20
February 17, 2020 1:47 am  

@negativevolume

Thanks for the reply. Yes, I meant visually. When I changed the size of my rebar in Section_Beam, visually the difference in the size is obvious. However, for my case, when I tried to changed the cross sectional area of my I-beam, there is no change visually on LS-DYNA. The cross sectional area of I-beam can be altered.

To model I-beam as reinforcement, which one will you recommend? Using shell or solid element?


ReplyQuote
Negative Volume
(@negativevolume)
Senior Member Admin
Joined: 2 years ago
Posts: 344
February 17, 2020 12:20 pm  

@saberman12

Yeah sometimes the versions of LS-Prepost won’t visualize changes for certain beam formulations. You can always check the volume of the beam in the d3hsp file after you run a simulation, to make sure that the cross section/volume that you are defining is being implemented.

And it really just depends on where the emphasis is on your model and how accurate you want the I-Beam to behave. I’m sure I can find some LS-Dyna studies which look at bending response differences between shells and solids.

If you are interested in loading the beam axially then maybe solids? If looking at bending then shells would be fine. You can always try a small comparison study between the different modeling forms and see what differences you find are.


ReplyQuote
saberman12
(@saberman12)
Junior Member
Joined: 1 year ago
Posts: 20
February 19, 2020 4:33 am  

@negativevolume

Thanks for your suggestions. I will try out your solutions.


ReplyQuote
Negative Volume
(@negativevolume)
Senior Member Admin
Joined: 2 years ago
Posts: 344
September 26, 2020 8:01 pm  

@saberman12

I'm checking in on old topics. Did you get your i-beam modeled using shells or beams correctly?


ReplyQuote
saberman12
(@saberman12)
Junior Member
Joined: 1 year ago
Posts: 20
October 13, 2020 10:12 am  

@negativevolume

In the end, I remembered modelling my I-beam using shell or solid elements. I was not able to model the I-beam using beam element. Modelling with shell elements was faster and easier.


ReplyQuote
Share: