Decking over concrete, patio and flower bed

Hi

We had a bomb shelter that we've now demolished which has left a concrete base that we want to deck over. To get a decent sized decking area (2.5m x 3m) we plan to cover an area of patio and a small flower bed.

We've bought some deck tiles and a frame from B&Q, but I'm not sure whether it has to be fixed to the ground or not. I've read differing things.

All the surfaces are fairly level, but may need some leveling before the joists go down. Do you think it would be ok to build the frame and then just put wood or paving slab wedges under to keep it level and keep it slightly off the ground to prevent rotting, or do I need to fix it into the concrete? If so how is it best to do this?

Thanks!

Yes, it must be attached to the ground or some fixed structure, to stopit bouncing and moving laterally under loading.

At some point there must be places where you can sink posts into concrete and attach the frame to them? See other posts concerning how to build deck framework, or come back with specifics.