A BOULDER APPROACH
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
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
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
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.
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.
Offers Excellent Strength-To-Weight Ratio
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.
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.