Unreinforced slab-on-grade crack repair

[GalileoG]

I have an existing unreinforced slab-on-grade that has recently cracked due to differential settlement. The cracks have largely stabilized but we are left with many cracks with widths ranging from 0.1mm to 20mm.

Typically for smaller cracks up to 4mm, we would require the cracks to be epoxied using gravity feed (Sikadur 35). As we have much larger cracks on this slab, I am trying to determine the most appropriate crack repair technique.

I would imagine a repair for the wide cracks would consist of cleaning and coating the inside walls of the crack with an epoxy (Sikadur 35) and then filling the crack with mortar and finished off with an epoxy seal. Does that sound about right for cracks exceeding 4mm in width?

Your thoughts would be appreciated.

 

[Ron]

If you have lots of cracks and they are due to settlement (are you sure?), then you likely have faulting at the cracks. If that's the case then the serviceability of the floor is compromised and individual crack repair is futile and useless.

Crack and seat the existing slab and provide a topping slab.