Industrial Concrete Floors
Increasing Concrete DurabilityWhat happens when you add steel fibres to concrete? This is a question that has been answered with increasingly more detail and precision since the introduction of steel fibre reinforcement in the 1960s. The advantages and limitations when steel fibres are added to industrial concrete floors is a complex and important topic for those designers and construction companies who build commercial structures.
In today’s construction industry, steel fibre reinforced concrete is gaining popularity in many types of floor construction. It is also seeing use as a replacement for structural reinforcement in other applications such as in harbor pavement, airport runways and locations where seismic activity is a consideration. There is no debate within the commercial construction industry that steel fibre can save money when compared to other reinforcing systems used in industrial concrete floors.
Polymer macro fibres and steel fibres are often used interchangeably in the construction of industrial concrete floors. Each product will extend joint width and reduce curling and they both can be mixed at high dosage rates without causing problems with the finishing or pumping of the concrete mixture. In general though, steel fibres are considered to be superior to polymer fibres but the two products are sometime used together for specific synergistic effects.
Properties and CharacteristicsChoosing the right type of steel fibre and the dosage rate within the concrete requires experience in construction, concrete applications as well as a good understanding of the characteristics of the steel itself.
- Aspect ratio is an important consideration when choosing steel fibre for use in industrial concrete floors. In simple terms, aspect ratio is the length of the fibre divided by the diameter. In general, a product with a higher aspect ratio will provide better performance.
- Tensile strength of the fibres is another consideration. Different types of fibres within the industry will range from 50,000 psi all the way up to over 400,000 psi.
- The length of the fibre will also vary depending on the application and the product type. fibres can range from a ¼ inch up to more than 2 inches. There is a trade off with fibre length in industrial concrete floors as the longer fibres will perform better but are much more difficult to mix into the concrete itself.
- The shape and perimeter dimension of the steel fibre product is the other important design feature. There are a myriad of shapes and configurations on the market, but the challenge is to come up with a shape that achieves the best anchorage ability and bond strength along the entire length of the fibre.