Toll Gates in France
Four toll gates of this type have been erected along the Amiens-Boulogne motorway. The swift assembly of the prefabricated modular roof elements meant a minimum impediment to traffic. The precast concrete masts are anchored in sleeve foundations. A 17x 17m square frame, consisting of trussed girders with diagonal bracing, is suspended from the tip of each mast by four rods. The Teflon-coated, self-cleaning, polyester membrane is spanned between the frame and a lower steel ring. The seams between the segments of the membrane are reinforced with strips that bear most of the radial tension loads.
