topic Re: Suspension Bridge Analysis Issues in Robot Structural Analysis Forum

Suspension Bridge Analysis Issues

Anonymous — Fri, 10 Mar 2017 08:38:29 GMT

Hi guys,

I am new to Robot Structural Analysis, and I am trying to model a suspension bridge. I did get convergence on my solution after I set the geometric non-linear property for my analysis. However, when I took a closer look at the results, I noticed there were negative moments at the mid-span of my suspension bridge, and when I checked the axial forces in the suspender cables, I realize the tensions at the two ends of the same cable are different. I have attached a simplified model of my bridge. Can someone help me take a look at the model and tell me what I am doing wrong? Any help will be appreciated! 🙂

Regards,

Cheng

Re: Suspension Bridge Analysis Issues

Artur.Kosakowski — Fri, 10 Mar 2017 09:00:37 GMT

, I noticed there were negative moments at the mid-span of my suspension bridge,

When you look at the deformation you will see that they match its shape. If you don't 'like' this (which for assembly case may actually be what you want) try to change definition of vertical cables (differentiate them for the end and middle parts of the bridge).

and when I checked the axial forces in the suspender cables, I realize the tensions at the two ends of the same cable are different.

It is as expected as due to self-weight being uniformly applied along the bar.

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.

Re: Suspension Bridge Analysis Issues

Anonymous — Fri, 10 Mar 2017 15:10:01 GMT

Just realized how ironic it was when I was doing self-weight load case and still ended up ignoring the self-weight of the cables. lol Thank you so much for replying!