So I have done a three point loading test on a piece of bone.
I have been able to obtain the Second Moments of Area $I_{xx}$, $I_{yy}$, $I_{zz}$. As well as the centroid. I also have the data from the experiment that gives load and extension.
However now I would like to obtain the stress for the specimen using complex or asymmetrical bending equation. How though do I find the moments $M_y$ and $M_z$?
Note this was a three point bending experiment so only one load was placed.