We have been involved in a number of projects utilising the use of ultra high modulus (UHM) Carbon Fibre >600Gpa as a means of reinforcing and extending the lifetime of ageing infrastructure. These tend to be bridges and tunnels with cast iron structural members installed in the days of Brunel. Often the structures are still in good condition but increased traffic levels and new buildings have increased the load capacity that they were originally designed to support.
At NORCO, we source this high modulus carbon fibre and directly manage the conversion to prepreg according to our specification. The plies of uni-direction carbon fibre are laid up into bespoke planks and cured under vacuum in our large ovens.
Where fire retardency is a key criteria these are encapsulated with Phenolic prepreg to meet FST requirements meeting rails standards.
These ultra-stiff CFRP planks are then bonded into place by the contractor using an epoxy adhesive. This additional strengthening saves huge costs in having to dig new tunnels or replace existing bridges and the work can be done overnight with minimum disruption to passengers.
In one large installation on the London Underground we produced 224 stiffening plates, which were bonded to cast iron beams using epoxy adhesive by the contractor.