The concept of using fibers as reinforcement is not new. Fibers have been used as reinforcement since ancient times. Historically, horsehair was used in mortar and straw in mudbricks. In the 1900s, asbestos fibers were used in concrete but once the health risks associated with asbestos were discovered, there was a need to find a suitable replacement.
In the late 50’s and early 60’s E glass and C glass were being proposed as reinforcements for concrete in Russia and China. It was thought that due to its very high tensile and flexural strength glass fiber would be a good reinforcement for concrete, which is inherently brittle. It was quickly realized however that E glass and C glass fibers were not stable in concrete due to the high alkalinity of the matrix.
Trials then focused on the use of low alkali cement and acrylic polymers to overcome this, but when they failed to solve the problems, the projects were abandoned.
In Europe, developments focused on the need to make the glass itself alkali resistant, and at the end of the 1960’s a suitable glass formulation was identified containing zirconia (Zr02), and after exhaustive trials the zirconia content was optimized at approximately 17%. In the 1970’s the technology was developed to produce alkali resistant (AR) glass fibers and the GFRC industry was born.
For almost 50 years of ongoing development, the industry now presents better quality glass fibers with a wider variety of sizing, new pozzolans to enhance the overall GFRC properties, low alkali cement to reduce the attack on the fibers, improved and diversified equipment, and more manufacturing methods. During this time, the market has witnessed continual growth in the volumes and the range of products manufactured. Today GFRC has become one of the most versatile building materials available to architects and engineers.
GFRC is known for its versatility due to its high strength and durability. It is an ideal material for Homebridge TM Culvert Wall and Raised Garden products. The mixes can achieve approximately 12,000 psi compressive strength, and 2,000 psi flexural strength after 48 hours of curing time.
Benefits of GFRC products include:
- Durability – GFRC has a high resistance to impact, weathering, freeze-thaw, and corrosion. There are no corrosive materials included in the product such as reinforcing bar, mesh, or other reinforcing materials.
- Lightweight – Because if its inherent strength, GFRC is relatively light compared to regular concrete which includes aggregate. GFRC is easier to handle, transport, and install.
- Sustainability and Green Building Credits – GFRC uses a low energy manufacturing process, re-cycled materials, and because if its strength, uses less material which results in a lower carbon footprint. GFRC can contribute points to achieve a LEED/Green Building Certification for a new or renovated facility. LEED Categories include Materials and Resources – up to 9 points; Innovation and Design Process – up to 5 points. For more information, visit the US Green Building Council website: usgbc.org
- Versatility – The mixes can be molded into intricate shapes and textures and is easily colored with integral colors that last virtually forever.
- Low Maintenance – High strength renders GFRC products resistant to degradation and staining, reducing maintenance and long-term Operational Expenditures (OpEx).