Bridge Construction

Bridge Construction. Mount Hope Bridge. , The Mount Hope Bridge was built as a private toll bridge by the Mount Hope Bridge Co. after state proposals for a public bridge were defeated. In 1927, Dr. David B Steinman, the noted New York bridge engineer, produced the design for a graceful suspension bridge. His firm, Robinson and Steinman, supervised its construction. The McClintic-Marshall Construction Company was the general contractor and the combined work force totaled nearly 500 men. , Steinman’s design included several innovations that allowed the bridge to be built in just 22 months with significant cost savings. with a main span of 1,200 feet and an overall length of 6,130 feet, the new bridge was the eighth longest bridge in New England until the Newport Pell Bridge was completed in 1969. , Construction began with the upper-arches and the viaduct spans at either end. Next came the main piers in the channel and the towers on top of them., which reached 325 feet above the water. Huge masonry anchorages weighing 8,000 and 27,000 tons were then built on either shore to anchor the two main cables, which were fabricated by spinning thousands of miles of steel wire back and fourth from shore to shore over the tops of the towers. Each cable is eleven inches in diameter, consists of 2,450 wire strands and weighs 350 tones. Once the cables were spun and wrapped, the steel frame of the central span was lifted into place and suspended from the cables by vertical hangers. The concrete roadway was then poured and on October 24, 1929, the Mount Hope Bridge was opened to traffic.