Scan-and-Solve for Rhino

Simulate Early, Simulate Often... In Rhino

Hello,

this is my first try of SnS, I just wanted to check how it works and whether it is suitable to my needs.

I have modelled a simple I-beam with two eyes at the ends (pivot bearings) and one eye in the middle (point load).

How to declare that the restraint is fixed in x, y and z directions, but has released rotational degree of freedom about z axis?

Why there are only three degree of freedom to edit instead of six (3 translations and 3 rotations)? See 01-restraint-example.jpg.

In my given example results were as if the ends of the beam were fixed, not merely simply supported.

Please give any idea to model it properly.

I have chosen "Principal tension / compression" for my output, (see 02-choice-of-output.jpg) but when I generated html report it contained only deflections and von Misses stresses. How can I declare what output should the report contain?

Thank anyone in advance for help.

Views: 889

Reply to This

Replies to This Discussion

Hello Jacek,

 

I'll work up an example for applying rotational restraints using a geometry similar to yours.

As for getting the report to generate additional outputs, you have to modify the report template as described here:

http://www.intact-solutions.com/sns_documents/sns_2014/reporting.htm

You need to add the following line to the report template:

##SCREENSHOT SOLUTION PTC

~Michael

 

Hello Michael,

thanks for report tip.

Meanwhile, I managed with restraints as shown on attached picture, and got good results

Maybe there is a better solution?

Hello Jacek,

That looks like it should work fine, there is still some resistance to rotation due to the Z-restraint on the bottom face, but the face is probably small enough it won't affect the behavior a lot.

Here's an approach that allows free rotation of the ends and provides a decent approximation of what you are trying to model:


If you are not concerned about the symmetry of displacement, you can also apply loads that are in static equilibrium and apply an edge restraint somewhere to ensure numerical stability.  Here a 2000 N load is applied up, two 1000 N loads are applied down:

The displacement field will not be symmetric:

 

But the strain and stress fields will be symmetric:


~Michael

Hello Michel,

thank you for help. Slowly I began to get a point how to manage with lack of rotational degrees of freedom at restraints. 

RSS

FOLLOW SCAN&SOLVE

© 2024   Created by Michael Freytag.   Powered by

Badges  |  Report an Issue  |  Terms of Service