Designer Seeks More Sites for Patented Economical Crossings
The designer of two hybrid bridges that currently traverse a fragile wetland at an Alaskan golf course recently received a U.S. patent and has formed a company with the contractor to market the technology. While Freespan Inc. has not sold any more bridges yet, it has proposals out for sites around the country.
Without large abutments and supports needed for a conventional footbridge, the "FreeSpan" bridges utilize epoxy-coated or galvanized prestressed tendons in a configuration of horizontal strands connected to steel and concrete abutments at both ends. Structural support is realized by strand tension. The design can accommodate vehicle weights up to 10,000 lb and spans of 400 ft.