I have a project that consists of making a footbridge (which will be used for maintenance) with iron beams. For my study I don't really know what to use as a finite element program. For catia, I don't know how to model the connections (embedded, pivot...), and for rdm7 for example, as there are no sheet metal plates to know how it resists, I don't really know how to find what load the beams that form the rectangle will support (see attachment). These are probably distributed loads, but I don't know how to determine their efforts
With so little information, how do you expect us to be able to help you. Post at least the 3D drawing and the file so that those who have CATIA can give you some lair points.
The PEF simulation is not voodoo, especially with a load of 3 tons.
Yes, it may bend a lot on long beams. That's precisely why I would like to be able to simulate everything to make a good compromise between what type of beam to use (IPN, IPE, HPE...) and what amount of material to use for reinforcements.
You don't seem to have the necessary information to carry out your project.
YOU SAY
- I don't know how to model the connections (embedded, pivot...),
- as there are no sheet metal plates to know how it resists,
- I don't really know how to find out what load the beams will support.
- These are probably distributed loads but I don't know how to determine their efforts
IN ADDITION - You don't say if the legs are recessed or only placed on the floor. - You don't say if your structure attaches to the top in what appear to be corner walls. - You say nothing about your framework (tube, angle, IPN UPN, etc.) - To take up @gt22 your bracing is weird and you don't have any gusset. - Your structure is just a wire (RDM 7 or mechanically welded sketch).
IN SHORT, start by making your gateway in 3D without forgetting any elements.
COMMENT I am not the last to help on this forum. But when I see that we want to do simulation as if to reassure ourselves, when most likely we don't master the subject and we don't bother to at least collect the right information: I find it very serious. I wouldn't say I'm furious, but it at least plunges me into an abyss of perplexity. A maintenance walkway must be perfectly safe for the precious human lives that will move on it and those that will pass underneath.
Zozo I understand that it can be revolting, I'm only in the learning phase for the moment, this is my first gateway. That's why I preferred to get help and see the sensitive points. So sorry in advance for my clumsiness.
- As far as the supports at ground level are concerned, the footbridge would just be laid. - It will not be in contact with any side wall, just placed on the ground. - The framework I was thinking of doing in IPE but with the simulation I wanted to know if I could save weight with another shape of beam. - On RDM7 I don't know how to put gussets, I guess you'll have to associate it with an equivalent link. - My structure is just a thread because I made the sketch on RDM7 and I didn't want to overload the drawing (which is empty, I design it).
For the beams I was thinking of taking IPE 300 and for the bracing IPE 160.
GT22 Indeed, my current system allows to perform the gateway function without taking into account the possibility of failover. It is with a staircase with 2 flights, which will be perpendicular to the long beams, that I intended to solve this instability due to the height of the footbridge.
Sorry, when we have the subject in front of us we sometimes have trouble giving all the information because we know it. One thing that bothers me is to know what is the load or distributed load that each beam will undergo. We start with a sheet of a certain thickness that will receive the weight of 3 tons. But I can't dissect the efforts to extract the information from each beam and node.
I'm a little late, but when I read the comments, I find you guys a little tense...
On the other hand, the approach of starting with a simple sketch and a quick predim seems to me just as commendable as starting with a beautiful 3D that doesn't work and that you will have to completely redo later.
That said, on the substance, I share the general opinion. The purpose of the forum is to unblock people, but not to do the job for them. It would therefore be good to try to move forward a little and ask more specific questions (how to model a particular phenomenon, or how to analyze an unconvincing result for example).
A few tips to get you started:
- In the absence of 3D, at least make a clear diagram of your problem (dimensions, environment, point of application of forces...). If you're just starting out, you can look on the net for examples of what is done as suggested by gt22.
- Model all the elements that must participate in the maintenance of your structure (if you plan to work your stairs, they must be included). Visually, your reinforcements don't seem very large compared to the rest of your structure.
- To check the stability of your structure, I advise you to apply 5% of the value of your vertical force horizontally at the floor level.
Once you've progressed on the base, it'll be easier to discuss the details.
If it takes me a long time to respond, it's normal, I take your comments into consideration and I raise the problem again. The 3D model is coming soon!
Hello everyone, here is my start of 3D platforming. The 15mm skirting boards are missing from the floor plate to prevent falling objects. The railings of the staircase are missing. The holes put in the floor are to let through wheels of diameter 7m and in addition the platform should have an electric hoist system to lift objects of about 300 kg.
-no anchoring in the ground - No bracing or gusset - no information on the assembly method (welding, screwing, riveting, SPIT) - The stairs that could have been used as reinforcement (as suggested by @chamade) will be inoperative from this point of view.
From my point of view, without anchoring in the ground and with such a high CG, it is not viable. Especially since the masses are notoriously underestimated. As indicated , without reinforcement and assembly in the rules of the art, you should not make a structure as drawn.
I withdraw from this discussion because I can neither endorse nor do the work in place of, and this because precious human lives are at stake.
