Concrete floor 3sqm - calculation help and strength?

[Chrissofsweden]

Length 30dm
Width 10dm
Height 0.5dm

150 liters?

300dm2 multiplied by 0.5dm = 150dm3 = 150 liters of finished cement

One bag gives 12.5 liters of finished cement = 12 bags (plus a few more bags

Background:
In the far end of our "cold garage," there's a spot of 1x3m that doesn't have asphalt but is just gravel. Yes, they filled the garage with asphalt 50 years ago.. The walls and ceiling are insulated, so the temperature is consistent. But I guess it's not insulated under the asphalt or the gravel spot. Do you think 5cm of coarse concrete K25 and reinforcement is enough? I really want a workbench at the far end of the garage, but dropping a screw there now would be a disaster...

A bonus question: You can mix about 150 liters fairly easily in a cement mixer if there are two people putting in the effort, right?

 

[klaskarlsson]

When it comes to the number of bags etc, there's a good thread here:

https://www.byggahus.se/forum/grund...-manga-liter-betong-far-man-pa-25kg-sack.html

Since you're only making a workbench, I don't think 5 cm with reinforcement mesh should be a problem regarding strength...

/K