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GENERAL INFORMATION

 

Glass fiber reinforced concrete ( GFRC ) is a proven engineered composite building material consisting of Portland cement, aggregate, water, glass fiber reinforcement and additives. The glass fibers reinforce the concrete, much as steel reinforcing bars do in conventional construction. The glass fiber reinforcement results in a product with much higher flexural strength than normal concrete, allowing its use in thin-wall casting applications.

For building panel construction, GFRC castings are manufactured by spraying a series of layers of polymer-concrete material with glass fiber reinforcement in a female mold. A steel frame is bonded to the casting, allowing the panels to be installed by bolting or welding the frame to the building's structural steel. The flex-anchors, which connect the skin to the frame, allow movement of the skin relative to the supporting structure.

By using pigments and finishing techniques, a wide variety of colors and surface finishes can be obtained, either to suit the Architect's vision, or to recreate historical building elements.

 

HISTORY

In the late 1960's, GFRC was first successfully produced in England. The key to success was the development of alkali-resistant glass fibers, capable of resisting the alkali attack that occurs when the fibers are mixed with normal hydrating Portland cement.

In 1980 the product began to be used in the USA. During the 1980's and 1990's, GFRC became widely accepted, and the industry has grown dramatically.

GFRC is also used for wall panels, spandrels, column covers, soffits, and architectural ornaments

In recent years, contractors in the landscape and pool & spa industries have discovered the benefits of learning how to use GFRC boulders and rock cliff panels for custom waterfalls and other water features at residential and commercial projects which--when designed, installed and colored properly--appear as if they were carved by erosion a thousand years ago.

The material is frequently specified by architects and engineers in historical landmark restoration projects and used to replicate deteriorated stone, cast stone, and even architectural terra cotta.

 

GFRC Offers Excellent Strength-To-Weight Ratio

One of the biggest advantages of GFRC is it's relative strength to weight ratio, which is far greater than that of ordinary hard rock precast concrete.

 

DURABILITY

Our exclusive GFRC mixture exceeds standard industry formulations that have been tested to achieve a tensile strength of up to 9000psi, compressive strength up to 1300psi, flexural strength up to 5000psi, and a permeability of 1200 coulombs in addition to having earned an "excellent" rating in freeze thaw resistance after withstanding over 300 rapid freeze thaw cycles considered to be the equivalent of 100 or more North East winters.

GFRC's permeability compares favorably to other cementitious materials. In laboratory tests, GFRC panels subjected to water blown wind of 75 miles per hour. Moisture absorption tests indicate an absorption rate in the 8 to 16 percent by weight range.