Diamond in the Sky - First of Two Ironton-Russell Bridge Towers Nearing Completion
SEGMENTS, FALL 2014, VOL. 59
The first of two 316-foot diamond-shaped towers to support the new Ironton-Russell Bridge over the Ohio River is nearing completion. The towers are founded on large diameter drilled shafts with rock sockets. When complete, the 900-ft (275m) main span will be the longest span the Ohio Department of Transportation has built.
A major crossing of the Ohio River between the towns of Ironton, Ohio, and Russell, Kentucky, the 2,616-ft-long (275m) replacement bridge will be a cast-in-place concrete, cable-stayed crossing with structural steel approaches. The main span will have two side-approaches measuring approximately 370-ft (113 m) each.
The new structure will provide two 12-ft driving lanes and two 4–ft shoulders. Span lengths for the approaches vary widely as they cross six different rail lines, the Ohio River levee and various city streets.
The entire structure is cast-in-place with 22,500 cy of reinforced (5.8 million lbs. of rebar) concrete, utilizing the cable stays to construct the bridge by the balanced cantilever methodology. Two anchor piers will be located on the river’s edge. This is the first known use in the USA of precast stay anchor blocks and the casting of the back spans in place using specially designed falsework. The unique approach to develop this alternative construction sequence ultimately saved ODOT $15.2 million over the next closest bidder on the project.
The new bridge is replacing the now outdated original Ironton-Russell Bridge that opened in 1922 as the first highway bridge along the Ohio River between Parkersburg and Cincinnati. The original bridge will be removed once the new bridge is open to traffic.