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The Fort Pitt Bridge
The Fort Pitt Bridge is located in Pittsburgh and spans the Monongahela River. The bridge is a functional structure constructed in the 1950’s in order to build up the metropolitan greater Pittsburgh area and to replace the old Point Bridge, which was built in 1927. It serves as an efficient, economical and elegant structure that successfully accomplished its goal of connecting Pittsburgh to its northern suburbs.

The Bridge was constructed in unison with the Fort Pitt Tunnels in order to link the city with southern suburbs making Pittsburgh more accessible. This made the bridge a social success because it provided a means for the general public to readily access the city, which in turn helped flourish the great city of Pittsburgh. Its contributions to the development of the greater Pittsburgh area rival those of the Liberty Bridge and tunnels, which were deemed a huge success. Also it is considered to be one of the more attractive modern bridges. Its aesthetics are heightened by the golden triangle of symmetry along the Rivers of Pittsburgh that it creates with neighboring bridges: the Fort Duquesne Bridge and the West End Bridge. The bridge was built hand in hand with the Fort Pitt tunnels, which was a $17 million dollar project. When compared to the construction cost of the Liberty Bridge and Boulevard, which was a $40 million project, the construction was efficient.

The Fort Pitt Bridge is the world’s first computer designed bowstring arch bridge built in 1959. The bridge is nearly identical to the Fort Duquesne Bridge, which was constructed around the same time, but coasted $550 million and took a total of 30 years to complete. The bridge is made out of steel and has a total length of 1,207 feet with a longest span of 750 feet, which is 200ft further than that of Fort Duquesne’s span. From this comparison it is evident that the Fort Pitt Bridge was much cheaper and it has a greater span meaning more material is needed in its construction. Also About 150,000 vehicles use the bridge every day. In a city with a population of 331,816, that means about half of the population is using the bridge, which means the bridge is worthwhile because it gets a lot of us.

The traditional construction method of build up members was used in its construction along with the period technique of using plate steel or plate steel with holes in place of v-lacing and lattice. The arch is constructed with riveted plates instead of being trussed, while the suspenders are wire cables. The deck also has riveted plates and is considered a warren truss structure. The cross bracing on the arch is also warren truss made, but it is made of oval-perforated beams. Finally the piers are faced with dressed stone.

The bridge is efficient in it’s use of material because the load is carried efficiently with minimal material, and appears light. The deck is used in tension to keep the arch, which is in compression to keep the bridge from collapsing. The arch is like a bow and the trussed deck is like the string. There are then tension supports in between to help bring the forces to the ground. The horizontal tension of the deck is carried up to the arch which is in compression by the vertical ties and is then brought to the ground.

The Fort Pitt Bridge symbolizes the gateway to Pittsburgh as a city of bridges. Travelers coming from the west emerge from the tunnels and immediately find themselves on the Fort Pitt Bridge bringing the golden triangle of yellow cross bracing of the bridge’s arches. Because of the view, the bridge is famous for being the “best way to enter an American city.”

The Fort Pitt Bridge was a successful project, and gives Pittsburgh its unique look. As the first computer generated bow string bridge, which is not a standard bridge type, there are still several bridges, especially in Pittsburgh, that replicate its design, such as the Fort Duquesne Bridge. Overall due to the Fort Pitt Bridge's Efficiency, economical efficiency, and elegance, it is considered to be structural art [|structural art]