A fibre-reinforced polymer (FRP) cycle footbridge has been proposed for construction in Bristol, United Kingdom for South Gloucestershire Council. The superstructure will span 54m, comprising a bowstring carbon fibre-reinforced polymer (CFRP) arch with a 5m wide glass fibre-reinforced polymer (GFRP) deck supported by stainless steel hangers. Recently, a methodology has been proposed that provides a structured process to assess the value of a structural health monitoring (SHM) system for a bridge prior to deployment. This methodology outputs a simple metric that quantifies the likeliness of an SHM system to yield value to an asset owner. This FRP bridge is used as a case-study to 'road test' this process. Two possible systems were considered: a system of accelerometers and a system of strain gauges. From the resulting discussions, a deployment of accelerometers received a value-rating (VR) of 4.2. A strain gauge deployment received 3.7. The scores will contribute to a monitoring specification for the FRP bridge which is currently in the design phase. Expansions to the methodology have also been proposed to better capture the potential value of an SHM system which would be of interest to structural engineers and researchers, in particular to inform model validation and research activities.

The Frampton Cotterell FRP road bridge deck comprises pultruded GFRP units which are laid longitudinally and are adhesively bonded transversely, in contrast to previous GFRP deck bridges where the pultruded units were laid transversely. This novel layout dictates that transverse distribution of live loading occurs only through the deck's flanges and entails possible transverse tension which should be controlled to avoid cracks through the bonded deck-deck joints. The present paper assesses these structural actions by interpreting strains and deflections recorded during lorry testing of the bridge. Transverse distribution is evaluated by comparing transverse profiles of recorded longitudinal strains and predicted longitudinal moments, with the conclusions qualitatively reinforced using a deflected surface based on the test recordings. Evidence of the deck acting as a continuum free of propagating joint cracks comes from the fact that the strains recorded during complementary lorry runs along the bridge satisfy the superposition principle, and that the recorded strain influence lines replicate an idiosyncratic feature of the moment influence line without redistribution effects. That feature was then exploited to inform the strategy for a braking test which produced valuable vibration data for the bridge. Test data integrity is corroborated by cross checking deflections recorded from different types of sensors. It is concluded that since longitudinal placement of pultruded decks enhances the versatility of FRP bridges, this sensor layout and data interpretation process may form part of a wider strategy for health monitoring of such bridges.

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