Rogue River Bridge - Gold Beach, OR
Posted by: 
silverquill
N 42° 25.630 W 124° 24.794
10T E 383744 N 4698173
Completed in 1931, this seven-span arch bridge was the first major structure in America to use the concept of the pre-stressed concrete arch. Designed by famed Conde McCullough the 1,898 foot bridge spans the mouth of the Rogue River.
Waymark Code: WM5WB7
Location: Oregon, United States
Date Posted: 02/19/2009
Views: 11
From the Wikipedia:
The Isaac Lee Patterson Bridge
The Isaac Lee Patterson Bridge, also known as the Rogue River Bridge and the Isaac Lee Patterson Memorial Bridge, is a concrete arch bridge that spans the Rogue River in Curry County, Oregon. The bridge carries U.S. Route 101 across the river, near the point where the river empties into the Pacific Ocean.
The bridge is 578.5 m (1,898 ft) long and consists of seven 70 m (230 ft) spans.[1] It was dedicated on May 28, 1932 and named after Isaac Lee Patterson, the governor of Oregon from 1926 to 1930.
A bridge with strong Art Deco influences, the Isaac Lee Patterson Bridge is a prominent example of the designs of the Oregon bridge designer and highway engineer Conde McCullough. It was designated a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1982.
McCullough employed a new method of concrete arch construction named the Freyssinet method, named after the French bridge engineer Eugene Freyssinet. This method uses precompressed arches which pemitted the use of smaller arch ribs, thereby reducing the weight and cost of the bridge. McCullough's design was the first usage of this technique in the United States.
Here the seven arches of the Rogue River Bridge provide a backdrop for the wreckage of the Mary D. Hume built in 1881 and in service for 96 years, the longest of any commercial vessel on the Pacific Coast.
From the
American Society of Civil Engineers :
Completed in 1931, this seven-span arch bridge was the first major structure in America to use the concept of the pre-stressed concrete arch. Each twin-ribbed arch spanned 230 feet. As an experimental structure sponsored by the Federal Bureau of Public Roads, it successfully demonstrated the engineering application of the pre-compression technique of the French engineer Freyssinet and formed the basis for its later widespread use.
The Rogue River Bridge was the most advanced concrete bridge in America when it was built. Distinguished bridge engineer Conde McCullough employed the techniques of Frenchman Eugene Freyssinet to create thin, graceful concrete arches for this seven-span structure.
Pre-compression of the concrete arch was achieved and, as a result of its success, pre-stressing became one of the hallmarks of American bridge building techniques.
Hydraulic jacks set at the crown of the arches were used to compensate for stresses induced by rib shortening, concrete shrinkage, temperature differentials, and movement of the fixed-end supports. These factors had previously been thought to limit the concrete arch to unyielding foundations, relatively short spans, or high rise-to-span ratios.