3-Point-Bend Test Simulation

Hello, 

I am trying to do a 3-point-bend test in Solid Works simulation. Right now I am running a static test. I want to progress to a non-linear dynamic test to produce failure but my static test is not running the way I want it to. I am doing a bend test on a 10k resin cylindrical rod. I want to fix the ends on "cylindrical supports" like an actual 3 point bend test. I also want to prescribe a displacement at the top-middle of the rod. 

I included pictures of my simulation to make more sense. 

Right now the problem is that when I animate my simulation the rod is inflating like a balloon and also moving off the support. 

I would appreciate any help anyone has to offer!

Simulation FEA, CFD & DYN 3 point bend test FEA