ᐅ Repairing holes in a concrete floor – debris and sand underneath

I would guess that this is actually debris and sand... try using a vacuum cleaner and hold it inside there for a bit (?)

Hi,
yes, it is outdoors. I can’t say for sure if it is concrete; it’s a typical flooring. Unfortunately, I’m not familiar with the wide variety of materials available. So I would prefer to approach the problem in a “lawn mower” way for now. Maybe in a few years everything in that corner will be replaced anyway. Until then, it should be watertight because I don’t know if there is just soil underneath. Right next to it is our house, and that should stay dry.
Best regards, Thomas.

So there is nothing underneath? No basement or similar? Just soil ...? Assuming yes, that is the case: This concrete slab (functioning like a paved surface) does not contribute to the building’s waterproofing. The house itself must be properly sealed. Any repairs are only cosmetic.

Explain the application to the building materials supplier you trust and buy a bag of screed cement (or similar). Chisel out the crack until the edges are solid and no longer crumbly. Then either sweep thoroughly or vacuum. Slightly dampen the area, then fill the crack and smooth it out. Make sure to compact well (tapping, tamping). Let it dry, and you’re done.

Hmm, judging by the condition of the floor, I suspect that they simply poured cement directly onto the rubble – real poor workmanship... otherwise, see above.

This will apparently be a structure intended as a parking space. This was a common practice in the past.
What is supposed to be underneath? A part of a basement?
I would consider what might be going on behind the stacked white calcium silicate bricks.


Regards

...thank you, thank you. Yes, the bricks are on the agenda. However, it is very full. Thanks to your advice, I will probably just leave it as a quick fix and simply fill it in with cement mortar. Clean it thoroughly beforehand and apply some bonding primer, and maybe sometime later do something entirely different that looks better...
Regards