Norco Composites undertook a joint venture project with Civil Engineering firm Concrete Repairs Ltd to design and manufacture a composite footway bridge. The finished and assembled bridge was installed in Sedlescombe, Kent in January 2015 on behalf of East Sussex County Council.
CRL contacted Norco as a potential partner to develop a composite bridge solution suitable to meet a wide market demand for bridges. Key market drivers CRL had identified were low maintenance, light weight for ease of installation, aesthetics and a target cost acceptable for decision makers to not be deterred but to select composites for their long term benefits.
A series of conceptual designs were reviewed, costed and assessed for their aesthetics before deciding on a design that was deemed to be most adaptable for bridges in the 8 – 18m size range. A detailed engineering study by Plysim looked at lots of different build strategies proposed by Norco and assessed the use of carbon fibre and bio-composites in the construction. The mould tool was specially designed to be adjustable for different widths, lengths and even camber.
To meet structural requirements the bridge utilises infused uni-directional fibres in the bridge deck and beam cappings combined with over-layed multi-axial fabrics at +/-45. Norco used a Vinylester resin system which offered suitable properties.
A fire retardant non slip product was applied using a spray gun which meets current surface spread of flame as well as non-slip standards required on public walkways.
The final bridge deck weighed 600kgs with the powdercoated & galvanised handrails weighing an additional 400kgs.
Installed within an hour of arriving on site, the 1 tonne composite bridge weighed one quarter of the weight of the bridge it replaced needing only a relatively small crane to complete the install. East Sussex council were also attracted by the huge on-cost reduction in maintenance.