Flowable Fill

[PT99]

Pressure Calcs for Formwork for Flowable Fill

Flowable Fill, 150 psi, weight 110 pcf, slump 9"

Formwork Max Pressure = Cc X Cw x (150 + 9000 x R / T)

What T to use?
Even though this is the fill material temp, would it be likely to be close to air temp because cement content is low? So 50 deg, NYC, now.

Cw = 0.5 x (1+ 110/145) = 0.88
Cw = 1.4 (additives in mix)

What R?
Or should I just use liquid analogy, P = 1/2 weight x height^2, and not bother with the above?

I need to be conservative on this. Any form bust is very serious in this location.

Total Height 10 ft, planning on (2) 5 ft high pours 24 hrs apart, Is this enough time for curing?

 

[dik]

Can you use this:

https://www.concrete.org/Portals/0/Files/PDF/CEU-347R-14.pdf

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

-Dik

 

[Ron]

With flowable fill you will not realize much benefit from adjusting "R". Because of the low cement content, it will not set up fast enough for R to be useful. Because of this, either use a fast R or just take the full liquid approach.

 

[PT99]

Thanks, especially for ACI document to review.
Fast R and liquid approach pretty much get the same force. And using T as close to ambient air temp is conservative even if technically not correct.
Curing time? 24 hrs? 48 hrs? Anybody know.

 

[dik]

Ron, yup... even if I'd consider this as SCC... full hydrostatic load without the max 'cut-off'.

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

-Dik

 

[AskTooMuch]

24 hours for flow fill usually enough but those are for mud slab of foundation.

 

[PT99]

Thanks,
This going into a sidewalk vault to be abandoned, under a New York City street.