The new $21.5-million Norridgewock Bridge—one of only two modern tied-arch concrete bridges to be built in the U.S.—is taking shape over the Kennebec River in northern Maine.
The new bridge includes a 300-ft center span and two 150-ft approach spans. Four of six transverse braces are now in place, along with 19 intermediate floor beams and three end beams. When opened this fall, it will replace a four-span concrete tied-arch bridge built in 1928, which was one of the first of its kind in the U.S., says Craig Weaver, senior project manager with designer Kleinfelder, San Diego. Kleinfelder worked with the contractor to modify the construction sequence. “Typically, there’s little on-site involvement from designers,” says Weaver. “But [the Maine Dept. of Transportation] gave us an extra fee to support their resident engineers because it is such a complex job.”