Honeycomb Sandwich panel (penetration)

[M2891]

Hi,
I've been carrying out penetration tests in the out of plane direction of aluminium honeycomb sandwich panels .

Can anyone tell me how to calculate the slope constant when you have load in Newtons, and diplacement in (mm), I think hookes law can be used although not sure how to apply it in this situation?

Also for UTS what x-sectional area should I use, i.e area affected, sample height, etc

I would really appreciate this information, It is really urgent that I get these results soon,

Thanks