Another cement floor lift question

[trdtaco]

We had a garage put on about 4 years ago. In anticipation of having a lift in at somepoint we used 300p tpi concrete and poured in additional thickness where I planned on putting the lift..

So fast forward now 4 years later I have a crack running directly over where the lift was going to be.

So my options at this point.. If i choose to cut the floor and repour 2 squares to set the lift post
on how big do these squares need to be? 3x3? Is this even a viable option or will that not provide the support and strength needed being a much smaller patch of concrete.

 

[mnwebb]

trdtaco how carefully was the ground prepped before the pour and did you have saw cut joints?

 

[trdtaco]

trdtaco how carefully was the ground prepped before the pour and did you have saw cut joints?

The floor was back filled watered and compacted. Obviously not enough tho. The garage is 40 by 35. There were no cuts. The contractor insisted the floor did not need it with the wire mesh in the concrete. Obviously Wong again.

 

[FTG-05]

Pics?

 

[rsanter]

How big is the crack?
How thick is the floor?
Odds are the manufacturer will say cut it out

 

[ConCretin]

Based on your description, the crack is more likely to have resulted from shrinkage than an inadequate base. Most lift manufacturers specify a minimum distance to from the posts to control joints. In practical terms there isn’t any difference between a control joint and a random crack.