Double Tee Precast cracks 2

[engq]

Greetings
we've recently installed double tee precast slab after almost two weeks cracks begun to appear and it rained and some seepage occured as shown in the photos attached. The cracks mostly less than 1 mm.
What would it be the cause.
Thanks

 

[hokie66]

I'm guessing they are plastic settlement cracks. Concrete in the stems settled before hardening, while the slab part was still supported on the form. The cracks were only noticed after the rain. Lack of adequate compaction is the culprit.

 

[JAE]

...and in addition to what hokie66 suggests it could also have been made a bit worse by a net difference in the prestressing compression in the web (where most of the tendons are) vs. the flanges which typically have only nominal tendons.
So the web compresses more than the flanges and you get a crack near the junction between them.

 

[SWComposites]

looks pretty ugly for a 2 week old structure.

 

[JAE]

I think the water makes the cracks look much larger than they really are.

 

[engq]

Thanks everyone.
Yes JAE, The water made way larger than what it's actually is,
Does it affects the load bearing capacity and is there any necessary repairs that should be made. There is a 5 cm concrete screed layer is to be applied

 

[JAE]

I would contact the double tee manufacturer and have them review it.

 

[JohnRwals]

Generally, double tee stems are more critical than flanges structurally.
Topping concrete will solve most crack related issues.
I wonder what causes this problem.
Either poor production technique, handling or torsion?