The construction industry is increasingly seeking innovation and efficiencies to drive down costs and provide a sustainable future. So why has it not accepted FRP composite materials to replace steel, concrete and timber as a structural material? John Drewett, director of Lifespan Structures, is optimistic that this will have to change over the next decade.

Fibre reinforced polymer (FRP) composites have been used by industries since the 1950s as a structural material. FRP consists of structural fibres bound in resin to transfer stresses and protect them. There are a variety of generic resins and fibres available which can be used to make up the composite material including organic fibres such as flax all with different performance characteristics. Careful design allows placement of the fibres in the most efficient orientation to resist the forces applied to the material when used in a moulded production method.

"The first footbridge delivered to East Sussex County Council in January 2015 weighed 1 tonne and replaced a 4 tonne timber bridge. It was delivered complete with surfacing and hand railing to site and installed within an hour."

Most industries have been using these materials for many years to replace traditional materials such as steel, aluminium, reinforced concrete and timber. Our vehicles have FRP composite body panels and if you can afford it the whole monocoque body can be made from carbon fibre composites. The latest aeroplanes such as the Boeing Dreamliner predominantly use composites and of course yachts and motor cruisers are almost always constructed with these materials.

The construction industry has been using FRP composites for 40 years beginning with GRP cladding panels for buildings and in the last 20 years ancillary equipment such as stairs, hand railing, and footway decking. There have been examples since the early 1990s where the materials have been used to construct exhibition pavilions, footbridges and some road bridges but these have been one off “pilot” schemes and progressed no further.

With the construction industry looking to become more efficient with better planning and innovation now is the time for a step change in the structural materials we utilise in the industry.

We need to transfer the knowledge and manufacturing experience from the aeronautical, automotive and marine engineering industries for the benefit of our construction industry – to bridge the gap,  providing lightweight off site construction of structural elements or complete structures which are cheaper and quicker to install, low maintenance, low whole life cost and reduced carbon and energy metrics.

I believe Lifespan Structures Ltd is the first UK Company to provide an integrated design and manufacturing service for moulded FRP composite bridges. The first footbridge delivered to East Sussex County Council in January 2015 weighed 1 tonne and replaced a 4 tonne timber bridge. It was delivered complete with surfacing and hand railing to site and installed within an hour. This bridge has won an ICE Award for Environmental Engineering and Sustainablility highlighting the benefits it provided in terms of the environment and the community.

"The latest aeroplanes such as the Boeing Dreamliner predominantly use composites and of course yachts and motor cruisers are almost always constructed with these materials."

This is not another one off pilot scheme but the beginning of a standardised bridge concept leading to efficiencies in design and manufacture. The business focus is on footbridges for spans up to 20m for the rail and highway sectors to develop industry confidence in working with these materials. Designed in accordance with the Eurocodes with a minimum service life of 60 years and minimal on-going maintenance. The initial costs are slightly higher than timber and comparable with steel but over a 60 year service life they are considerably cheaper.

As the industry quickly becomes confident in using these materials more applications can be considered across the building and civil engineering trades. The design capabilities are immense with the orientation of fibres and combination of different materials complex but structurally efficient structures can be constructed as well as standard utility items.

Within ten years when the revised Eurocodes include FRP composites, the supply chain is established and our university graduates have the design skills, these materials will be considered alongside traditional steel, concrete and timber options. It is an opportunity for the UK construction industry to lead the world in this technology and it has the support of Government which has invested over £50M establishing the National Composites Centre near Bristol.

John Drewett is a director of Lifespan Structures