How would you solve this surface with beam/floor joist?

[Manja-20]

The sketch shows the basement walls, on which I will lay a floor structure.
I would prefer to avoid having pillars to support it.

 

[Anonymiserad 122206]

In theory, you should be able to add a floor of CLT. However, I don't know what their maximum dimension is...

 

[Jc1972]

Beams dimension 45x220mm c24 will hold. C-c 600mm works but probably does not meet the deflection requirements. C-c 300mm I believe does. On top of the beams, you'll likely place floor particle board, and it's important to screw and glue it down as it stiffens significantly. One or two rows of cross-bracing also help.
If you google wood floor structures and span tables, you'll find charts.

 

[Jc1972]

Here you have a table.

 

[Manja-20]

Beams dimension 45x220mm c24 will do. C-c 600mm works but probably doesn’t meet the deflection requirements. C-c 300mm I think does. On top of the beams, you probably lay floor chipboard and it’s important to screw-glue it as it significantly stiffens up. One or two rows of (cross) bracing also help. If you google wooden floor joists and spans, you’ll find tables.

I want it to be as rigid as possible, so I thought it would require some support beams on 460 with about 300 in between or similar along the short side.