In fibre reinforced concrete, some or all of the reinforcing bars are replaced by integrally mixed fibres. The fibres used for structural applications are either steel or high-performance plastic. NZS 3101:2006 sets out design rules for steel-fibre reinforced concrete. Lower modulus plastic fibres can also be used to control plastic shrinkage cracking in concrete that is placed under adverse weather conditions. Well distributed fibres ensure an even distribution of fine cracks when the concrete is loaded. Fibre reinforced concrete can be designed with high toughness and ductility; attributes that suit applications such as shotcrete-applied support in mining, slope-stability and erosion protection. Fibre reinforced concrete is also widely used in blast-resistant design and in ground-supported floor slabs and topping screeds. Researchers are also currently developing applications aimed at using fibre reinforcement to enhance the seismic resistance of concrete structures, both for new construction and for retrofitting existing buildings.
Recommended sites for further information:
AZOM (The A to Z of Materials) www.azom.com
BOSFA (Bekaert OneSteel Fibres Australasia) www.bosfa.com
NZS 3101:2006, Chapter 5 www.standards.co.nz
Construction Chemistry Directory www.baustoffchemie.de/en/db/
Institute of Materials www.iom3.org