Exact load to get a right mechanical properties

Hi everyone,

I am working on a new material, and I am trying to find the exact load ( right pressure load) that I need to apply on the tope surface of the material with fixed boundary conditions in the bottom to find the right mechanical properties like ( modules of elasticity, reduced modules, hardness and toughn). I'm doing the simulation on Abaqus first and compare them with experiments in my laboratory. So, how can I measure the right load that  should apply it? 

Thanks,