Wall Form Pressure Calculator

Lateral concrete pressure from pour rate and temperature per ACI 347R.

Pour rate (ft/hr)

Concrete temperature (°F)

Form height (ft)

Concrete unit weight (pcf)

Chemistry coefficient (Cc)

Tab to move between fields

Lateral pressure (psf)

792.9

Lateral pressure (psi)5.51

Equivalent fluid head (ft)5.29

Full hydrostatic (psf)1,500

Design pressure (psf)1,030.7

How to Use This Calculator

Enter the Pour Rate in feet/hour and Concrete Temperature at placement.
Enter Form Height, Concrete Unit Weight, and the Chemistry Coefficient (Cc) for your cement type.
Review Lateral Pressure in psf and psi — this value drives all subsequent formwork design.
Check Equivalent Fluid Head to understand what fraction of full hydrostatic pressure governs.
Use Design Pressure (with 1.3 safety factor) to size form ties, walers, and strongbacks.

How the result changes with Chemistry coefficient (Cc)

Pour rate (ft/hr): Vertical rate of concrete placement in feet per hour.
Concrete temperature (°F): Temperature of fresh concrete at time of placement.
Form height (ft): Total height of the vertical form from base to top of pour.
Concrete unit weight (pcf): Unit weight of concrete. Normal weight is 145-150 pcf.
Chemistry coefficient (Cc): ACI 347 chemistry coefficient: 1.0 for Type I cement, 1.2 for Type I with retarder, 1.4 for other types with retarder.

Lateral pressure (psf): Maximum lateral pressure on the formwork per ACI 347R.
Lateral pressure (psi): Same lateral pressure converted to pounds per square inch.
Equivalent fluid head (ft): Height of concrete that would produce this pressure if fully fluid.
Full hydrostatic (psf): Maximum possible pressure if concrete were fully liquid (upper bound).
Design pressure (psf): Lateral pressure multiplied by 1.3 safety factor for form design.

Identify Input Parameters
4 parameters
Pour rate (ft/hr) = 5, Concrete temperature (°F) = 70, Form height (ft) = 10, Concrete unit weight (pcf) = 150 = 5 input(s) provided
Calculate Lateral pressure
792.9 = 792.9
Calculate Lateral pressure
Lateral pressure = lateralPressure / 144
5.51 = 5.51
Calculate Equivalent fluid head
Equivalent fluid head = lateralPressure / unitWeight
5.29 = 5.29