After truss analysis, beam elements shown tapering

[caseyrt]

Hey all,

I'm working on a school project that involves me solving a truss system that would be suspended at one end from a fixed wall (think a cantilevered scaffold). There is a distributed load across the top and two point loads near the free end. The elements on the top and sides are beam elements. The problem is that after I solve the system, the elements on the top that run from the fixed end to the free end are shown to increase in cross sectional area toward the free end. I have no idea if this is an issue or what it means or how to fix it. Any help is greatly appreciated!

I uploaded a screen shot, URL following.

 

[petb]

Hi,

It's a bit hard form to really see what happens. One thing you can check is whether your beams are rotating around the neutral axis. The same graphic phenomena exists for beams if rotation around the axis is not constrained in a modal analysis.

HTH
petb

 

[caseyrt]

They are rotating about the neutral axis. I will try constraining against that and I'll see how that affects the solution. Do you happen to know if it's purely a graphical issue or if it also affects the stress results?