Bridge deck soffit shutters
Bridge decks place high uniform loads on the plywood soffit, often with post-tensioning ducts creating local pressure points. 18mm-21mm hardwood-core WBP panels on steel beam supports at 300-400mm centres handle these loads without excessive deflection. The finish must be smooth to allow proper asphalt adhesion later.
Pier and abutment formwork
Bridge piers are poured in lifts of 3-4 metres using steel-framed shutters lined with film-faced plywood. The panels are stripped and re-fixed vertically, which stresses the lifting points and corners. Specify reinforced corner profiles and hardwood-core panels to resist this handling cycle.
Wing walls and curved parapets
Wing walls transition from vertical to horizontal and require plywood that bends to compound curves without cracking. Test samples to the design radius before ordering. Thinner 15mm panels on closely spaced supports sometimes work better than 18mm panels for tight radii.
Weather and site conditions
Bridge sites are fully exposed to wind, sun and rain. Store plywood under a secure site cover when not in use. The combination of UV, heat and dust accelerates film ageing; inspect panels monthly and retire any with visible film degradation before it affects concrete finish.