Causes of Grid Pattern Cracks in a concrete pathway?

[atef81]

Hi,
I found the cracks shown in these photos in a concrete pathway. The cracks seem like a "grid-pattern", and also they seem to be perpendicular to sawn joints.
Just wondering what can cause this pattern and why the slab would crack perpendicular to the sawn joint although the joints are places to make the pathway square in shape?

Thanks in advance.

 

[Tomfh]

Plastic settlement cracks? Does it match the bar spacing?

 

[atef81]

Hi @Tomfh,
I could not "see" settlement in the pathway. and the reo is a layer of SL82 mesh, so it is square, while the pattern is square/rectangular and much larger than the mesh grid.

 

[canwesteng]

Maybe better compaction in the middle of the fill below the pathway, and the outsides are settling.

 

[Retrograde]

Was the slab poured on a hot sunny day? Or a windy day? Looks like shrinkage cracks due to inadequate curing.

 

[dik]

Looks like improperly cured...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Tomfh]

I could not "see" settlement in the pathway. and the reo is a layer of SL82 mesh, so it is square, while the pattern is square/rectangular and much larger than the mesh grid.

I meant plastic settlement of the concrete as it cures, not settlement of the pathway. The patterns looks like it could be multiples of 200

 

[r13]

I am with Tomfh. Can you measure/mapping the smoothness over and around a cracked area. You need very good instrument, the "settlement" could be so fine.