In this article we delve into the history books and discover how GFRC has evolved throughout time.
The concept of using fibres as reinforcement is not new. Fibres have been used as reinforcement since ancient times. Historically, horsehair was used in mortar and straw in mudbricks. In the 1900s, asbestos fibres 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 fibre would be a good reinforcement for concrete, which is inherently brittle. It was quickly realised however that E glass and C glass fibres 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 optimised at approximately 17%. In the 1970’s the technology was developed to produce alkali resistant (AR) glass fibres and the GFRC industry was born.
For almost 50 years of ongoing development, the industry now presents better quality glass fibres with a wider variety of sizing, new pozzolans to enhance the overall GFRC properties, low alkali cement to reduce the attack on the fibres, 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.