# Linear elasticity boundary conditions

I came across this post from the computational science board: https://scicomp.stackexchange.com/questions/26495/well-posedness-of-elasticity-boundary-conditions

I agree with the posted answer, but I am wondering if there should be an additional condition on the bottom side, such that $$\sigma_n=C$$ at the bottom? This would give the problem an explicit balance of forces, but I don't know if this is needed?

If the problem is solved without this additional constraint, could it be possible that $$\sigma_n$$ at the bottom side end up $$\neq C$$?