Deck Unsupported Span

[scav000]

Ok, that';s correct, and don't forget the modulus value too!

So, now, in the same example, work out the Z and I with a central hole of 100mm diameter and 200mm and then 300mm diameter.
And what do you notice?

Wow, I actually cannot believe it. If you treat them as the same section. The Section modulus and area inertia don't change that much.
Thank you for not losing patience in teaching this to me.

 

[Ad Hoc]

....The Section modulus and area inertia don't change that much....

Well, that is what you are to calculate, so you can then see the difference in values, if any, between the without the hole and with progressively larger holes.
Only once you have done that, can you draw any conclusions.