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Distinguished Contributor
Jummybear
Posts: 128
Registered: ‎11-16-2011
Accepted Solution

Truss and tube connection design

804 Views, 3 Replies
03-20-2012 02:13 AM

Hi,

I have 2 questions about tube connections (while designing truss construction):

1. If I design a truss in module "truss 2D design" i can apply only nodal loads but often you have an upper chord loaded with a uniform load and in this case you have a bending moment in the bar. In truss design module you are not allowed to apply uniform bar load, so you can't get a chord loaded with an axial force FX and bending moment at the same time. What are you recommendations or advice about this? How to design in such circumstance the structure in most effective and accurate way? I have 2 solutions, but I want your confirmation that i do it in right way:

1.1 Calculate truss construction in truss 2d module with nodal loads, get only axial FX forces and apply separately the bending moment by hands and verify the section with FX and My in some subsidiary program (excel for ex) :smileyhappy:

1.2 Calculate truss in frame mode, but in this case we get a rigid(fixed) connections between bars. To make them pinned, we can define releases in necessary nodes.

1.3 Calculate truss in frame mode and define diagonals like truss bars or tension/compression bars which transfer only axial forces. I suppose, that i am on right way :smileyhappy:

 

2. Second question about connection design module. I can define only symmetrical connections (chord-2 diagonals-1post), but in reality such connections are not symmetrical, can i design not symmetrical connections in ARSA? Probably in something will change in version 2013? Look at attached pictures, i hope you can understand what i am talking about.

 

Thanks.

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Product Support
Artur.Kosakowski
Posts: 4,832
Registered: ‎12-17-2010

Re: Truss and tube connection design

03-20-2012 02:31 AM in reply to: Jummybear

1. My approach would be to define continuous chords (frame model, no releases at the locations of intermediate posts or diagonals) and either apply releases at both ends of posts and diagonals (if bending due to self-weight matters) or define them as truss bars (but without non linearity: tension/compression only)

 

2. I'm sorry but such connections are currently not available (and will not be available in v.2013).

 

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
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Distinguished Contributor
Jummybear
Posts: 128
Registered: ‎11-16-2011

Re: Truss and tube connection design

03-20-2012 04:00 AM in reply to: Artur.Kosakowski

Thanks for the reply. If u could add such connection type to wishlist it would be great.

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Product Support
Artur.Kosakowski
Posts: 4,832
Registered: ‎12-17-2010

Re: Truss and tube connection design

03-20-2012 04:09 AM in reply to: Jummybear

I will.



Artur Kosakowski
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