Fire protection of concrete structures: Fibrexpan®
Fibrexpan® is a spray-on fibrous coating that can be used for fire protection of concrete structures. Fibrexpan® is a dry material composed of slag wool, hydraulic and semi-synthetic binders and various additives; It is supplied in flake format.
Fibrexpan® is a spray-on product. The spraying technique, also known as flocking, consists in applying Fibrexpan® fibres under pressure, using special machines.
The sprayed thickness will be defined according to the desired fire insulation rating.
The spraying machine comprises a feed hopper, a carding device, a blowing device (fan, turbine or blower), and a hose for conveying the mixture to be sprayed. Plus a spray gun used to apply the fibrous Fibrexpan® mixture, and water.
The product is carded in the machine, then fed to the spray gun by means of compressed air. Water-fed nozzles are placed around the hose outlet to wet the product before it is sprayed onto the substrate.
The thickness of the spray-on coating will vary according to the thickness of the reinforced concrete slab and of the steel coatings, depending on whether this involves:
• concrete slabs: Fibrexpan® thickness will vary between 44 and 215 mm for an REI performance of between 30 and 240 minutes.
• beams on single or continuous concrete supports with width greater than or equal to 150 mm: Fibrexpan® thickness will vary between 40 and 80 mm for an REI performance of between 30 and 240 minutes.
• concrete walls: Fibrexpan® thickness will vary between 44 and 80 mm for an REI performance of between 30 and 240 minutes.