I'm after a bit of help please from those in the know.

Just purchased this....



...for my newly acquired lockup!!

Its basically an old barn so the ground is just compressed dirt basically, so I need to lay some concrete for the ramp to bolt to.

Question I have is how deep does the concrete base need to be (ramps are 8ft high if it matters) and how much floor coverage do I need - can I just lay a strip similar width & length as the centre base of the ramp or does it need to be more?

Thanks in advance!!