Can you re use mot sub base ?

[dal]

Hi, so I'm I have broken up my old concrete patio because it was too high for the new patio & it had several large cracks in it. Now underneath they appear have put in a sub base but they haven't crushed it so I've dug that out and put it to one side there is some soil mixed in with it but it's mostly sub base.
So as per title, can I re use this. I intend to put about 2" of the old stuff down and crush it then add another 2" of new stuff and crush that down.

Cheers.

 

[Badger_grr]

Yes that completely fine. You will get better compaction with a mix of fines in there as well. This is perfect time with the weather to do this work. In construction crushed material is always dug out and stockpiled for use back filling later.

Are you planning to cast a new slab on top of this material? If so make sure you wet the sub base just before you pour otherwise the water will be sucked away from the concrete and decrease its strength.

 

[dal]

Well i was planning on laying a full mortar bed directly onto the sub base then slabbing on that ( porcelain paving)