Crack control in PT Slab
Crack control in PT Slab
(OP)
I have a PT slab over a parking level. Half is in heated space while the other half is exposed. I really would like to avoid expansion joints. What other options besides typical T & S reinforcing would help prevent temperature and shrinkage cracking (due to differential temp. changes)? Any help is greatly appreciated.






RE: Crack control in PT Slab
RE: Crack control in PT Slab
RE: Crack control in PT Slab
RE: Crack control in PT Slab
How big is your slab?
RE: Crack control in PT Slab
RE: Crack control in PT Slab
Provide additional tendons at the perimeter beams that go between the conditioned to unconditioned space. They will experience double bending as they transition from the conditioned to unconditioned space. Additional tendons will be required at the interface between spaces as well.
Increase slab thickness - takes longer for daily temperature changes to affect the slab and reduces long term shrinkage and creep (V/S is larger).
If you want to model it, find the longterm volume change differences from your conditioned space to unconditioned space. Determine the required axial force needed to transition from one length to the other (F = PL/EA) and then, after careful deliberation, install the expansion joint (smile).
RE: Crack control in PT Slab
I would vote for 300 psi(about 2.1 MPa) minimum.