Hello everyone,
I am modeling a simply supported (pinned in the midplane) of the sandwich beam (with PVC foam core). When I directly choose the midplane of the foam and assigned the pinned BC's I will get a large stress concentration in the foam near the point where I assign the BC's and the foam has stress above the failure stresses. I think this is not working. Then I tried to attach a rigid surface to the edges where I will assign the BC's then, I got center deflection as what it was predicted by the analytical solution but I still have the problems. I tied the sandwich edge with the rigid body using "tie constraint" using "surface to surface" contact option. When I have a rigid body I have to define a reference point to assign BC. I assigned the BC's to the reference point. What happened is, I will get all the U1, U2 and U3 to be zero only at the reference point but all the point on the midplane line I will get the deflcetion. Further, when I mathced the strains, I will have very good match at the center but the strains at the edges didn't matched. Can anyone help me to figure out this problem. Thank you.