# Engineering Formulas and Notes Area of hexagon A = (12/5) r**2

height above water given thickness and density: H = thickness – (thickness * (weight/displacement))

Density of sea water 1.03 (nominal)

Pressure increase with water depth .43 psi/ft

Outward force F bearing on perimeter of mold:

¼ scale model=770 lbs/face, full scale= 40 tons/face

Tension thru mold walls and hinges for hexagon:

F sin(60) / 2 sin(30)

for full scale , this is 35 tons.

PSI per megapascal: 1 PSI = 145 Mpa

For density range .3-1.8, cellular concrete compressive strength has range 100-3600 PSI,

So at density 1.0, expect maybe 1000-2000 PSI.

1 gal = 3.63 Kgm = 3.63 L = .129 cu ft

Density of cement = 1500 kg/m**3

Dry density of sand (loose) = 1600 to 1700 kg /m**3

Density of normal concrete = 2400 kg/m**3

Foam: Ratio water to detergent = 36:1

Expansion ratio

From Concrepor: = 12:1

From Norizal = 30:1

From our foam generator: 20:1

The scale model requires 97 gal. water just for cement.

Requires 1,100 gals water for the cell bags.

Floatation Flooded

Cells Bouyancy Freeboard

3 8 tons .6 ft

4 23 1.8

5 38 3 ft

6 53 4.1ft