# Symmetry in finite element

1. Jun 10, 2013

Hello,

I have concrete box and steel box and bolt as illustrated in picture one(quarter shape),so my questions are:

the key points in symmetry for the quarter of the shape are:
1.prevent translation in the two plan direction(allow translation in the direction vertical to the shape)
2.prevent rotation in the three directions or what( this is exactly my question, i believe i have to prevent rotation in the three direction, or maybe only around the the two axis(plan axis, not the vertical )
3. do i need to apply those conditions at the all section boundary for example steel and concrete and etc .
4. apply quarter of the load (right?)

The second question is in picture 2,the area in which i pointed here demonstrate that the bolt here is smaller than the steel(in perimeter,so don't match exactly, and concrete show up, so do i need to apply conditions on this small area

Note this area will represent only gap in the real situation see picture 3 pls

http://img35.imageshack.us/img35/1336/47179197.png [Broken]
http://imageshack.us/photo/my-images/189/15136950.png/
http://imageshack.us/photo/my-images/853/66361611.png/

Last edited by a moderator: May 6, 2017