Damien constructed a timber joist base for his garden shed using out 68mm x 750mm ground screws.
"My project was a solid garden shed, strong enough to store my small ride on mower in (and all my other garden junk).
Your ground screws are a fantastic product, it was significantly easier and cheaper than the alternative options (like putting down a concrete base).
A nice benefit is that the entire structure is elevated off the ground, so no worry about rot for the wooden structure."