GRP stands for glass-reinforced plastic: a composite material made of a resin (usually polyester or epoxy) reinforced with glass fibres. The resin forms the matrix and the glass fibres carry the tensile forces. The result is a material that is light, strong and resistant to rust and most forms of corrosion. It is also known as fibreglass, GFRP, or GVK/GFK in Dutch and German.
Properties
- Light and strong — a high strength relative to its weight
- Corrosion-resistant — does not rust and withstands many chemicals
- Freely formed — can be cast or laminated into almost any shape
- Low maintenance — long service life with little upkeep
- Non-magnetic and electrically insulating
Application in construction
GRP is used in many ways in building:
- Roofing and rooflights — corrugated sheets and translucent panels
- Water engineering — gratings, walkways, handrails and bank protection that must not rust
- Pipes and tanks — chemically resistant pipes and storage tanks
- Reinforcement — GRP reinforcing bars (composite rebar) as a rust-free alternative to steel, for example in aggressive environments
- Facade elements and profiles — light, low-maintenance sections
One point to watch is that GRP releases dust and fibres when worked; grinding and cutting require good extraction and personal protection. GRP is also harder to recycle than metals.
Related terms
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