Ribbed tunnels The system, entirely designed and built in CAODURO®, consists of aluminium ribs and cold bended sheets in order to provide the greatest flexibility and design freedom. There are in fact no particular constraints as regards, for example, the arch height, the distance between the ribs and the transparent sheet thickness. Standard production uses polycarbonate sheets in clear transparent or opal white colour, extruded aluminium alloy ribs protected by natural, black or dark brown colour anodizing or epoxy powder RAL 9010 white colour coating. Different colours are available upon request. Polycarbonate sheet has a good cold bending performance which, while manufacturing, causes a certain stress that has to be taken into account when choosing the right sheet thickness according to the tunnel diameter. All these details allow us to offer a roof cover with cold bended sheets less stressed and, as a result, with greater technical characteristics and durability. The use of alveolar polycarbonate, due to its particular rigid structure (multiwall with ribs), requires great attention not to use cold bended sheets with a lower bending radius than those recommended by the sheets manufacturer, so that stress does not affect mechanical performance of the product over time. Alveolar polycarbonate, moreover, presents a marked decay of optical characteristics (yellowing, fragility). In order to reduce this phenomenon, standard CAODURO® tunnel production with this kind of sheet is exclusively employed using both UV rays protected walls. All models, systems and structures shown below are protected by international patents. A - Clear span B - External support wall C - Overall tunnel dimension F - Rib spacing H - Arch height CAODURO1 S.p.A. Via Chiuppese, 15, 36010, Cavazzale (VI), Italy Phone +39 0444 945959 - Fax +39 0444 945164 [email protected] - www.caoduro.it