Truss system allows continued traffic flow during rehab of historically significant bridge

Parsippany, N.J. — Acrow Bridge recently completed installation of a modular steel structure to maintain traffic flow during renovation of the 68-year-old George E. Tryon Bridge over the south fork of the Smith River near Hiouchi, Calif. The bridge had been found functionally obsolete at inspection, with a deteriorating lead-based paint matrix.

The rehabilitation project involves replacing the existing 206-foot by 24-foot steel arch bridge with an aesthetically similar concrete arch span 231 feet by 32 feet, 4 inches. The additional width will eliminate one-lane sections of the roadway and allow room for bicycles and pedestrians along with significant tourist traffic.

Initial bids were over budget, and Acrow collaborated with Flatiron Construction who, acting as the CM/GC, value engineered a hanging formwork truss bridge outside the existing steel structure. The Acrow structures utilized were two 155-foot clear spans, 9 feet out-to-out.

The job posed numerous difficulties, including restricted staging areas at the site. Additionally, the bridge is located on the very steep, rocky banks of a 60-foot-deep environmentally sensitive gorge, and the area is home to threatened and endangered wildlife species. Because the adjacent land is owned by the California Department of Parks and Recreation, the U.S. Forest Service and private individuals, multiple-agency coordination was necessary.

“This was a challenging job, but ultimately very rewarding” said Jack Arizcuren, Pacific States Sales Manager at Acrow. Added Bill Killeen, President and CEO of Acrow Bridge, “This project is a great example of how Acrow systems can provide creative solutions to difficult situations and provide value to contractors and government agencies alike.”

Posted in Structural News | July 29th, 2016 by