Glass fiber reinforced concrete is an extremely strong architectural material. This strength comes from the addition of alkali-resistant glass fibers that are interspersed in a concrete mixture. After the concrete cures, the glass fibers serve the purpose of internal support for the concrete element, yielding an architectural feature that has improved tensile strength, impact strength, and flexural strength.
The strength and durability of GFRC relies on the correct application of fiberglass into the base mixture, and this process is one that requires careful science.
How Factors Affect GFRC
The glass fiber reinforced concrete mixture is made of Portland cement, aggregate, water, and the AR glass fibers. The ratio of all of these different ingredients can vary and will affect both the workability of the mixture and the final product in terms of appearance, longevity, and strength. But it is the glass fiber that has potentially the greatest effect on the GFRC mixture, depending on:
- Amount of Glass Fiber – Getting the right amount of glass fiber is a balance. Without enough fiberglass, the final product will be weaker, but too much fiberglass makes it difficult to work with and hard to correctly form in molds. Typically around 7% to 10% of the mixture can be composed of glass fibers. This will yield both manageable material and a reliable finished product.
- Orientation of Glass Fibers – The direction of the fibers is what gives the GFRC its strength. A completely random glass fiber orientation will require more fiberglass in order to achieve a result that has enough glass pieces laying in the correct direction, but there are methods that provide a less random distribution.
- Application Method – There are several ways to mix in fiberglass to the concrete mixture. One of the most popular is to mix it in directly and then pour the entire mixture into molds. The second method, known as spray up GFRC, uses special equipment to spray the glass fibers directly into the mold after adding the concrete mixture. This method also has the benefit of increasing the number of glass fibers that have the optimal orientation.
Getting the correct mixture and application process is a complicated process. Working with an experienced GFRC manufacturer ensures that you get the best possible results. GC Products has specialized in GFRC architectural elements for many years and uses proven techniques for manufacturing our architectural products. Learn more about our process and what sets our work apart at GC Products. Contact our team for a free quote.