Building the Bridge

Building the Bridge. . , Bridge Structure , Superstructure , The Harris Structural Steel Company of New Jersey supplied and erected the bridge's steel superstructure. The company employed 222 men, including 150 ironworkers by September 1956. Established by George W. Harris in 1915, it was among the largest steel manufacturers in America by World War II. The company focused predominantly on high-rise building construction, but it began to compete for bridge work during the Depression. Other projects included the Castleton and Rip Van Winkle Bridges across the Hudson, the Brooklyn tower of the Verrazzano Narrows Bridge, and buildings such as the Port Authority Bus Terminal and the Daily News Building., Substructure , The Merritt-Chapman and Scott Corporation built the bridge's concrete and granite substructure employing 207 men by November 1954. Known as the "Black Horse of the Sea” the company began as a marine salvage operation in 1860. By the 1950s, it had expanded into industrial, marine, and heavy construction projects around the world. To complete the foundations of the giant Mackinac Bridge in Michigan, they mobilized the largest bridge construction fleet ever assembled to that date. Key projects included bridges on the Mount Vernon Memorial Highway, Glen Canyon Dam, Delaware Memorial Bridge, Walt Whitman, and Bridge, and Throgs Neck Bridge, Photo Caption: The "Runaway Black Horse" was the emblem of the Mermitt-Chapman and Scott Corporation., Box Piers , Box, or hollow, piers were used on the KRB where the continuous underdeck truss bridge met the girder structure of the bridge approaches. Pier 12 on the west and Pier 22 on the east are the box piers. They contain several floors and chambers accessed from the upper and ground levels, in addition to housing electrical equipment and providing catwalk access. The piers also provided a temporary office during construction where workers could pick up their paychecks., Clearing, Rough Grading, and Paving , The clearing and rough grading of the 0.67-mile-long west approach was completed by Philip Totonelly Company, Inc., of Newburgh. Totonelly had completed numerous highway construction projects in the region. Work on the east approach was carried out by the Grandview Construction Corporation (right) of Mount Vernon, which was operated by brothers Anthony, James, and Dominic Mirabelli., The Horn Construction Company of Merrick, on Long Island, paved the approaches and bridge roadway, employing 60 men. Founded by Moses Hornstein, the company specialized in heavy construction and engineering projects and was a sub-contractor to the Harris Structural Steel Company. Other projects included the Brooklyn-Queens Expressway, the Gowanus Expressway, and Battery Park City., Mohawk Ironworkers , Mohawk ironworkers from Kahnawake (south of Montreal Canada) were among the crews erecting the bridge's superstructure. Mohawks have worked as ironworkers since the 1880s, when the Dominion Bridge Company employed Mohawk men in return for building on Mohawk land. Mohawk ironworkers have worked on numerous bridge and "high steel” building projects across the US, including the Empire State Building, Chrysler Building, Rockefeller Center, the World Trade Center, and Freedom Tower. Known as "skywalkers" many have lived Gowanus section of Brooklyn commuting home to Kahnawake on weekends to see their families., Tremie Concrete , The use of tremie concrete enabied the bottom of the caisson to have the first layer of cement poured into the flooded caisson. This method enables large amounts of concrete to be deposited at the bottom of the pier foundation (highlighted in yellow) without the need for dewatering, as was necessary with previous bridge foundations. To ensure the concrete doesn't spill out as the pipe is lowered through the water, a temporary cap is placed over the end. Once the cement begins to pour, it forces the cap off the pipe. Tremie concrete cures with almost no cracks or imperfections because it is cooled by the surrounding water.