FEM Analysis on Steel Wires

[vkulikajevas]

I am looking for a best way to run analysis on Steel Wire support. Structure height is 5-6 m.

It has a support from 3 steel wire cables.

I need to find how rigid the system will be using certain wire gauges and sizes. 

Can anyone help me the best way to run simulation?
The problem is how to model the cables? Should they be done as a cylinder with Sweep operation? Will this work?

[vkulikajevas]

I am looking for a best way to run analysis on Steel Wire support. Structure height is 5-6 m.

It has a support from 3 steel wire cables.

I need to find how rigid the system will be using certain wire gauges and sizes. 

Can anyone help me the best way to run simulation?
The problem is how to model the cables? Should they be done as a cylinder with Sweep operation? Will this work?

[JDMather]

The only way you will get anything close to useful information is to use the Frame Generator and Frame Analysis with beam elements.  Wire rope isn't the same as a Frame Generator component, but might at least give you some ballpark behavior.

[JDMather]

The only way you will get anything close to useful information is to use the Frame Generator and Frame Analysis with beam elements.  Wire rope isn't the same as a Frame Generator component, but might at least give you some ballpark behavior.

[vkulikajevas]

But the nature of steel wire is its flexibility. You don't have that with a beam of steel.
It is somehow amazing, how Inventor (Including Solidworks too) after 20 years doesn't have Steel Cable Feature.

[vkulikajevas]

But the nature of steel wire is its flexibility. You don't have that with a beam of steel.
It is somehow amazing, how Inventor (Including Solidworks too) after 20 years doesn't have Steel Cable Feature.

[hosford]

Just a thought.

Because steel cable can only be useful in tension, why not test a 2D model where the cable is in tension using a strut of equal strength in tension?

[hosford]

Just a thought.

Because steel cable can only be useful in tension, why not test a 2D model where the cable is in tension using a strut of equal strength in tension?

[KakaSungura]

I would use Autodesk Nastran for this.

To model the steel cables, I'd create a part by sweeping along a path, then set that part's iProperties to the type of steel you want. So yes, your suggestion on how to model the steel cables is right, according to me.

PS:

Are you talking about this kind of cable?

An approximation (using a cylinder) is enough. You don't have to model the individual strands. Engineering is lots of approximations.

[KakaSungura]

I would use Autodesk Nastran for this.

To model the steel cables, I'd create a part by sweeping along a path, then set that part's iProperties to the type of steel you want. So yes, your suggestion on how to model the steel cables is right, according to me.

PS:

Are you talking about this kind of cable?

An approximation (using a cylinder) is enough. You don't have to model the individual strands. Engineering is lots of approximations.

[vkulikajevas]

Thank you for your reply. Yes you have the right picture of cable.

The thing I think it is important to get into account the flexibility of cable.

Take 1 m of 1 cm^2 section Steel rod - Bend it, 

and take 1 m of 1 cm^2 cable - Bend it. I am betting you, that you will get much better bend results in the cable than in a rod.

In my situation, I have tower which is supported by 3 cables, 2 cables will be in tension and 1 will be in compression (Forces shift of course, but the Cable - rod under compression would not get the results I search for, and make construction much more rigid that it is in life).

Do you understand now, that the flexibility in these configuration differs a lot, that is why you will get different results in calculations. And approximations in this case is really big. Unless there is a way to define higher elasticity to the material itself, and make it's property to act as a cable? In this case, that might just work.

Maybe there is a way to do that? 
Assign a Steel Wire - Cable Elasticity to certain rod extrusion for Stress analysis to treat them as cable?

[vkulikajevas]

Thank you for your reply. Yes you have the right picture of cable.

The thing I think it is important to get into account the flexibility of cable.

Take 1 m of 1 cm^2 section Steel rod - Bend it, 

and take 1 m of 1 cm^2 cable - Bend it. I am betting you, that you will get much better bend results in the cable than in a rod.

In my situation, I have tower which is supported by 3 cables, 2 cables will be in tension and 1 will be in compression (Forces shift of course, but the Cable - rod under compression would not get the results I search for, and make construction much more rigid that it is in life).

Do you understand now, that the flexibility in these configuration differs a lot, that is why you will get different results in calculations. And approximations in this case is really big. Unless there is a way to define higher elasticity to the material itself, and make it's property to act as a cable? In this case, that might just work.

Maybe there is a way to do that? 
Assign a Steel Wire - Cable Elasticity to certain rod extrusion for Stress analysis to treat them as cable?

[swalton · Accepted solution]

I believe that Inventor Nastran (available in the Collection) is a better tool for this type of problem.  It has a cable element, which the Inventor Professional FEA tool does not.

See: https://knowledge.autodesk.com/support/inventor-nastran/learn-explore/caas/CloudHelp/cloudhelp/2018/...

I'd do a few tests to make sure that the behavior of the cable element matches your expectations. (Only tension loads, no compression loads)

I would not rely on the stiffness of your steel cable to carry any compression loads in the real world.  I'd expect the cable to buckle or kink under a real-world compression load.  

[swalton · Accepted solution]

I believe that Inventor Nastran (available in the Collection) is a better tool for this type of problem.  It has a cable element, which the Inventor Professional FEA tool does not.

See: https://knowledge.autodesk.com/support/inventor-nastran/learn-explore/caas/CloudHelp/cloudhelp/2018/...

I'd do a few tests to make sure that the behavior of the cable element matches your expectations. (Only tension loads, no compression loads)

I would not rely on the stiffness of your steel cable to carry any compression loads in the real world.  I'd expect the cable to buckle or kink under a real-world compression load.