Patching void from removed post tie

I had posted a few years ago when removing some post ties from a patio slab. The slab was going to have a gazebo, but I opted to go with a pergola instead. So a few of the post ties I installed were no longer needed.

I removed the ties, and patched with a skim coat patch compound. Three years ago, I had patched 4 ties, and 3 have held up great. This one popped out after the first winter, note the crack in the slab.

Thoughts on how to properly patch this? I suspect the surface could be roughed up more so it bites more, but I think the crack may continue to cause movement and give the patch trouble during freeze/ thaw.

A skim coat won't hold up over a moving crack during freeze-thaw cycles. You need to chase the crack out, clean it thoroughly, and use an epoxy injection or a heavy-duty polymer concrete patch that actually binds to the old slab.

Thanks Carchie. I will read up more on those processes. Much appreciated.