Robot Structural Analysis Forum
Welcome to Autodesk’s Robot Structural Analysis Forums. Share your knowledge, ask questions, and explore popular Robot Structural Analysis topics.
cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

lifting the construction

93 REPLIES 93
SOLVED
Reply
Message 1 of 94
mortel09
6059 Views, 93 Replies

lifting the construction

How can i simulate that the construction is getting lifted in robot. The construction i have build is going to be lifted onto an oil rig. how do i simulate this in robot?

93 REPLIES 93
Message 81 of 94
Rafacascudo
in reply to: Rafacascudo

Some weak springs estabilizing supports on the right places were enough to get good results

Also changed the analysis type in the cross beam model from Large displacements to regular linear analysis.

models attached.

 

If your crane is tall enough ,on the cross beam model , the best place would be lifting from the beam extremes not in the middle portion of it. It is causing high bending moments on it



Rafael Medeiros
Robot Structural Analysis

Message 82 of 94
MOJTABA256
in reply to: Rafacascudo

Thank you so much for your helps 🙂 

 

Now I am going to compare different lifting configuration. I am going to compare story drift of each configuration together as one of the important parameter causing to out of tolerance during module installation. What is your opinion? What type of parameters during lifting process can lead to out of tolerance issue during installation causing to rework? Thanks again for your comments

Message 83 of 94
Rafacascudo
in reply to: MOJTABA256

Hard to tell .This depends on each country code. Each one has its rules. But of course in all of them ,the structure has to be checked OK regarding the forces that appear during the lifting process.



Rafael Medeiros
Robot Structural Analysis

Message 84 of 94
MOJTABA256
in reply to: Rafacascudo

Thanks for your comments.

 

I think that it can be more interesting if I can simulate the module dynamic behavior during transportation. For this purpose, I have to model the truck floor underneath the individual module as well as its support conditions during transportation. Then I must shake the truck floor during transportation using random floor vibration to see how much transportation loads  will affect on module structural properties. 

 

For the first step, could u please tell me how I can model a truck floor underneath a module as well as its support condition? Thank u so much

Message 85 of 94
Rafacascudo
in reply to: mortel09

Sorry for the delay.
I never have done an analysis like that
Maybe there are some codes that provide how to do this, but none there I know.
If you want to shake the structure using Robot, probably will be using Time history analysis.
Or maybe some sort of "fake" seismic analysis which I also don't know how to do it as there are no earthquakes in Brazil.


Rafael Medeiros
Robot Structural Analysis

Message 86 of 94

You may also consider use of these types of loads:

 

forces of inertia.PNG

 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.



Artur Kosakowski
Message 87 of 94
MOJTABA256
in reply to: Rafacascudo

Thanx a lot. I will let you about my progress

Message 88 of 94

Thanx dear Artur. I will use them and ask you if I have any question. Thanx again

Message 89 of 94

Hi, 

@Artur.Kosakowski  wrote on MESSAGE 59:

I have made a test model and tried to iterate the position of the support till the moment the values of bending moments is small enough to be neglected. Basically I started with step a and then I adjusted the support position moving it according to the values obtained from the reactions:

 

x movement = MY / FZ

y movement = MX/ FZ

 

Is it x or X? Is it MY or My? Is it MX or Mz?

Here's a link to @Artur.Kosakowski 's message:

https://forums.autodesk.com/t5/robot-structural-analysis-forum/lifting-the-construction/m-p/3670382#...

Any help would be highly appreciated.

Message 90 of 94
HoshangMustafa
in reply to: mortel09

Hi @Krzysztof_Wasik

Any thoughts would be highly appreciated.

Message 91 of 94

Hi @HoshangMustafa 

Answer regards adjusting support node position in attached models steps.zip.

MZ and MY , FZ  are reactions (in node 5) , while x and y are  support node position correction distance. Both (reactions and distance corrections) are calculated in global system of coordinates (X,Y,Z)



Krzysztof Wasik
Message 92 of 94

Hi @Krzysztof_Wasik 

Thanks for your reply.

I made an excel sheet for the reactions MY, MX, and FZ.

I calculated the corrections for positions of node 5 according to the reactions.

It seems that @Artur.Kosakowski subtracted x eccentricity for each iteration while he added the y eccentricity. How he came to this?

Message 93 of 94

Hi @HoshangMustafa 

To avoid signs analysis in respect to global axes direction(which is of course possible) I would use 2 iterations with +and - sign for calculated offset, then I would apply this sign which reduces reaction moment.

Similar effect can be obtained by adjusting node 5 X and Y coordinates to structure center of gravity available in Analysis >Calculation notes>Full or Simplified note (in few iterations).

 

Refer to 

https://forums.autodesk.com/t5/robot-structural-analysis-forum/lifting-concrete-box-support-reaction...



Krzysztof Wasik
Message 94 of 94

Hi @Krzysztof_Wasik 

Your help is highly appreciated. Thanks a lot.

Can't find what you're looking for? Ask the community or share your knowledge.

Post to forums  

Autodesk Design & Make Report