Caboolture Arboretum Pedestrian Bridge Renewal

Walkers at the Caboolture Arboretum cross the river tributary on a new composite fibre bridge of the same length, width and level as the old one, on the same alignment and the original abutments. The old bridge's steel beams had corroded in a low floodplain crossing, and the new structure has no corrosion mechanism for Council to maintain.

In a design flood the water sits a metre over the deck, carrying a 1.2 m debris mat at 2 m/s. The 1.4 m handrail is fixed with shear bolts calibrated to let go under a log strike. The flood takes a replaceable rail and leaves the bridge in place. Reusing the abutments came down to weight: the light FRP superstructure fitted within the load they already carried, which kept the job out of the watercourse.