Thickening an L-stone using formwork and concrete?

Hello,

I have a retaining wall with a thickness of 25cm at the terrace due to the slope. It was too short for me, so I had an L-stone added. The L-stone is 12.5cm thick. To create a straight edge when paving, I now want to "thicken" the L-stone with concrete. So far, I have mainly found information on complete walls or bases for fences, etc. Now I have a few questions.

- Do I have to formwork the entire depth of the L-stone? That is, should my concrete pour reach as deep into the ground as the L-stone goes? That is 1.30m total height minus the foot.
- Or can I gravel up to half a meter in height and only formwork and concrete the last 60cm of height?
- Do I need to set reinforcement? If yes, how much?
- As a "base," do I have to pour a lower layer first before concreting up to the full height?
- How important is frost resistance for such a small project? Will the concrete otherwise crack?

I could hand the whole thing over to a company, but I feel like doing something myself for once. I would appreciate helpful tips.

Honestly, that will never lift!

Better cut the other wall to the same width or attach a lid to it.

Honestly, that will never hold!

Did you mean "hold"? Why not? Gut feeling or what happens then?

I certainly won't cut into my €2000 retaining wall.

I haven't yet understood how a cap helps to pave against it, but it gives me another idea.

For example, a stainless steel sheet bent into a U shape that I can slip over the wall from above. On the side facing the paved area, I let this sheet hang down longer so that paving can be done against this sheet.
In the area of the L-stone, a cavity is created between the sheet and the L-stone. I might be able to fill that later.

Maybe instead of shuttering, one could also "glue" a whole curb stone of the necessary thickness in front (already concreted in). After all, there are curb stones all around the paving.
Then from above maybe again this sheet so that the botched work is not visible.

Hello Kaspatoo

I have had good experiences with "Reparaturbeton". It won’t work with normal concrete.

Steven

Is repair concrete not rather intended for cracks and broken corners, but not for casting an entire block? Why wouldn't it work with normal concrete? What would not work there?

Hello Kaspatoo

Repair concrete hardens more than "normal" concrete. If you apply concrete too thinly, it will crumble sooner or later.
Repair concrete would (probably) hold.
Personally, I wouldn't do that. I would thicken it somehow differently. Possibly a curbstone of suitable thickness.

Steven