ᐅ Frost protection (frost-free foundation) for concrete support columns through insulation

We are building on a slope. The terrace in the basement level is covered by the floors above. The floors above are supported at the outer edge of the terrace by concrete support columns.
We now want to expose the supporting foundations of the columns on the downhill side facing the garden, in order to create a small flat lawn area despite the sloped terrain.
The structural engineer sees no structural issues but says that for a frost-protected foundation the soil must remain 80 cm (31.5 inches) deep in front of the column foundation. My question:
Is it possible to achieve frost protection for the frost-protected foundation by adhering suitable insulation material to the column foundations on the downhill side,
to build a raised bed in front of it that only extends 50 cm (20 inches) into the garden?

Could you upload a sketch?
Basically, there is the concept of a frost skirt, where insulation extends beyond the concrete slab. Something like this might be applicable in your case, but I’m not sure if it’s planned correctly. It is important that the ground beneath the columns remains frost-free.

I simply made a sketch based on my understanding of the issue... But it should illustrate the general requirements for frost protection. Otherwise, as WilderSueden already mentioned, a frost barrier made of insulation material is needed. The frost line must be at least 0.8 m (32 inches) below the foundations everywhere.

I couldn’t have drawn the sketch any better, thanks! What I’m wondering is whether the blue line can be shortened if insulation is applied in front of the exposed foundation parts (behind and beneath the raised bed)?