A glass smooth concrete surface is an immaculate canvas for artistic versatility and permanence. It is the only truly UV immune surface possible as evidenced by its stature in the world's infrastructure.
Cast in non porous pvc molds, there is no water or moisture egree out the front or sides of tile, only the back side. When they are hardened sufficiently, after twelve to eighteen hours, the remaining moisture exits all surfaces, but in a diminished amount through the tile face. This dense smooth surface will have water bead on it, no penetration at all, while vapor can still exit, like a Goretex fabric.
The system utilizes jigs to make repetitive precision cuts and components to rapidly and easily make molds whose exactness can be imparted to precast concrete thousands of times. Setting up the fences and stops for these jigs and subsequent fabrication is tedious and laborious. Permanent work stations are recommended for each procedure so continuing manufacture is fast and easy.
Expanded steel is the perfect embedment to create a tenacious bond, spread over a substantial surface area. A cover to a densely consolidated tile face of a quarter inch and 1-3/4" depth of embedment also reinforces the tile at the point of its maximum deformation under compressive loading.
Full slot and spline bonding of the perimeter to adjacent tiles provides a high performance mechanical barrier against infiltration.
The panel is a mini yet potent structural geometry of beams top and bottom with thickened vertical rib columns at embedment points.
An example of columns and beams supporting a cast in place concrete slab. This is an onsite system to greatly reduce materials handling. Once wo uld think filling smallish molds would best be done from a small mixer. This turns out to be more laborious than it's worth under some circumstances. One needs at least a ten cubic foot mixer to handle a full sack of portland cement. Then a supply of three, four, or five gallon buckets, depending on the burliness of the laborers. Lifing buckets of sand, gravel, and cement into a mixer all day is a lot of work, although that is what I've done most my life.
Maintaining quality control is more difficult as the moisture content of the aggregates can vary day to day.
If the labor of manually lifting the concrete requirement for a building can be eliminated, then that's a huge step forward.
Since a concrete truck dumps alot of concrete quickly, mold filling has to go very fast. A hopper with four dispensers is employed.
The molds are set on a digital scale under the dispenser and filled to the appropriate weight within about six seconds. The readout is mounted to the vertical side of the dispenser.
It then slides immediately to a table behind where the coffer insert is installed, the expanded steels already prepped.
Two people lift the filled mold into the curing cart. When full, it's replaced.
To maximize the time, concrete from the ready mix truck is first deposited into the mold dispensing hopper, then into the walls already installed, then lastly, back into the dispenser.
Using "self consolidating concrete" (scc) helps speed the process. The mix design needs to hold the high slump (flowability) for 50 minutes to exit the dispenser efficiently.
Filling 300 molds, at an average of 37 pounds concrete per mold, over 50 minutes, which equals 3,000 seconds, with four dispensers, is 75 molds per 3,000 seconds, equals one mold per 40 seconds per dispenser.
These numbers will of course adjust some with experience. Although it's a very busy time, extraordinary value is being created.
What is the materials cost?
The predominant size that can be taken as the average is the 24 inch by 16 inch tile. It has two expanded steels. It's area is 2-2/3 square feet, and takes 36 pounds of concrete. The perimeter and vertical ribs are two inches thick. It tapers to one half inch in the coffer area.
There's reference in the American Concrete Institute Building Code (ACI) that addresses a unreinforced concrete wall's bearing strength.
In this formula, Pn is the capacity of the wall panel given its length, Ag is the horizontal cross sectional area taken at its minimum amount through the coffers, lc is the length of the tile, 12, 24, and 36 inches, and h is the height of the tile, 16 inches for each tile.
The total tile capacity is then divided by its length in feet to see the capacity per foot, so the amounts are directly comparable.
The amounts are then further reduced by a capacity reduction safety factor of 0.85 known by the Greek letter "phi". l
So one sees the useable load capacity per wall face is 15,000 pounds per foot.
What is the embedment strength of the expanded steel in the back of the tile according to Code?
Three diamond wide "inch and a half number 9 expanded steel"
Strand = 0.15" wide x 0.12" thick, area = 0.018 square inches, 6 strands, total area = 0.108 sq in
Assume useable strain = 0.003 inch per inch, Modulus of elasticity = 29,000,000, allowable stress = 87,000 pounds, concrete fails first
Embedment depth = 3/8", tile width each side of spline = 7/8"
Concrete spline retention per foot Vc = 2 x sqrt 4,000 x 3/8 X 7/8 x 12" = 498 pounds horizontal force per panel seam, two joined panels = 498 x 2 = 996 pounds
For exterior walls, poly iso rigid insulation creates both the tile void to displace concrete and it bonded to the full tile area backside. Air infiltration is stymied.
A workable spreadsheet can be downloaded by clicking on the image below.
It is best to have Open Office installed on your computer. It can be downloaded free here .
The pale yellow boxes can have their value changed by clicking the box, entering a new value, then hitting enter. Everything will automatically adjust to the new enty.
If you have any questions, simply call me. 720-213-8044.
The average retail price of all tiles is $12.44 per square foot.
To approximately calculate tile quantity for any plan with a 9' 4" interior ceiling height, multiply the area of the floorplan by 3.2.
For example, a 2,000 square foot floor plan would require about 6,400 square feet of CBS tile. That would equal a tile cost of 6,400 x $12.44 = $79,616.
Your concrete wall inside and outside cost would be equal to $79,616 / 2,000 = $39.81 per square foot of floor area.
This is high side approximate, will vary depending on plan, but at least is a starting point.
For a producer/builder, the installed cost of the system could be done for about $4 per square foot of tile.
This is the latest, most improved and efficient system yet for CBS. The first use will its Beta trial. The figures are determined from a most conservative perspective by the inventor of the system and his years of experience. Real results may be better or worse. The spreadsheet can easily be modified and illustrate the entire picture.