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The largest composite bridge in the world, first bridge span with 100% recycled composites outside USA

The largest composite bridge in the world, first bridge span with 100% recycled composites outside USA

A 32 feet wide, 8 span, 540 foot long Knickerbocker, the largest composite bridge in the world, is now open in Boothbay, Maine. The solution lay in hybrid composite beams (HCB) manufactured by Harbor Technologies. Developed by HC Bridge Company, LLC, the lightweight beams are made using fiber reinforced polymer. Used in conjunction with concrete and steel, the beams make a stronger, longer lasting bridge with an installed cost that is comparable to the traditional materials used to construct bridges. The HCB combines strength and stiffness of conventional concrete and steel, with the lightweight and corrosion advantages of advanced composite materials. The result is a cost-effective alternative for major infrastructure projects with sustainable structures that are lighterweight, safer and longer lasting than conventional bridges. This bridge, built in 1930 saw major superstructure rehabilitation in 1983. But because of its proximity to the tidal waters with only 4-feet of clearance at high tide, a replacement bridge able to better withstand the elements was mandatory. Approximately US$11 mln for construction of bridge projects, which include composite components, was funded as part of the initiative. In order to comply with the hydraulic criteria for the new bridge, the HCBs were designed to match the recommended 33 inch depth box beams to maintain the required vertical under clearance. Further, similar to the proposed precast box-beam bridge, the HCB framing system was limited to two 60-foot end spans and six 70 foot interior spans resulting in an eight-span bridge with a total length of 540 feet. The beams were also made continuous for live load with negative moment reinforcing steel cast over the piers in the 7 inch concrete topping slab. The design was impacted at the substructure units because the dead load was significantly less than the original precast design, however, the engineering team had to design for significant wave action.
What makes the Knickerbocker Bridge unique is not only the HCB framing system, but the fact that this will be the longest composite vehicular bridge in the world, the first to be made continuous for live load, and the fact that this has been accomplished with a structure that was no more expensive than a conventional concrete box beam bridge.
Axion International, a leading producer of industrial building products and railroad ties made from 100% recycled plastic, has received a purchase order for its innovative Recycled Structural Composite (RSC) material, which will be used in the construction of a plastic bridge in Scotland, the first of its kind outside the US. The bridge will be approximately 12 feet wide x 90 feet long and will be used to replace an existing steel beam and timber deck road bridge. The existing bridge is supported by two masonry�built piers and abutments, which are in good condition and will remain in place to support the new bridge. The clear span is 28 feet between piers resulting in three effective spans at 30 feet, representing the longest single spans yet constructed using this unique material. The bridge has been designed to European standards to carry a load of 45 metric tons. The new bridge will be manufactured and prefabricated in the United States at Axion�s plant and will be shipped to Liverpool via container ship and then on to Edinburgh. The new bridge will be shipped in six sections (two per span), and due to the pre-fab nature of the bridge, it is expected to be assembled onsite with relative ease. The bridge is expected to be fully manufactured and installed by October 2011, before Scotland�s winter season. Developed in conjunction with Rutgers University�s Materials Sciences and Engineering Department, Axion�s proprietary RSC material is inert and contains no toxic materials. It is impervious to insect infestation, will never leach toxic chemicals nor warp. Because it is lighter than traditional materials, transporting RSC is less expensive and reduces energy costs. In addition, they are completely recyclable at the end of their functional life.
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Complete UPVC pipe extrusion set up

Complete UPVC pipe extrusion set up