Five More Beautiful Bridges by John Yang
This article was inspired by a recent article by Abhiram Singireddy. I love bridges and I wanted to share some more amazing bridges.
1. Leonard P. Zakim Bunker Hill Memorial Bridge
This bridge is located in Boston, MA. It was designed by the late Christian Menn and completed construction in 2003. It is a fan-type cable stayed bridge. Built to replace an older truss bridge, the new Zakim bridge is truly a work of structural art. The towers take a trapezoidal shape below the deck and join near the top resulting in an obelisk-type shape. The use of concrete in the towers and choice to have white cables makes the design elegant but interesting.
2. George Washington Bridge
The George Washington bridge connects New Jersey to northern Manhattan. It is a twin-deck suspension bridge, opened in 1931. It was designed by Othmar Ammann, who was an apprentice of Gustav Lindenthal at the time, although he was becoming more independent. Interestingly, at the time, Lindenthal felt that NYC needed a locomotive bridge near midtown. This was understandable as private automobile use was not widespread at the time. However, Ammann looked to the future and foresaw that New York needed an automobile bridge and not a rail bridge. Indeed, Ammann was right as public automobile ownership did increase in the years following. He decided to build it in northern manhattan, as the land would be much cheaper there. Given that this was during the Great Depression, this was a highly economical approach and was well accepted. Observing the towers, we see that they have a steel truss design. Originally, the towers were meant to have a stone facade to hide the structure. However, the idea was abandoned after construction in order to save costs.
3. Verrazano-Narrows Bridge
The Verrazano-Narrows Bridge connects Staten Island to Brooklyn. It was also designed by Othmar Ammann and opened in 1964. It was the longest spanning suspension bridge in the world at the time of opening. The design for the Golden Gate bridge was inspired by the Verrazano-Narrows Bridge. This bridge has a notable lack of cross-bracings in the towers at mid-height. Indeed, the structure did not require it, nor did the Golden Gate Bridge require it. The addition of cross-bracings in the Golden Gate Bridge does not add structural value to the towers, but one can argue that the cross-bracings and art deco facade of the Golden Gate Bridge towers contributes to its status as an international icon and symbol. Every year, the TCS New York City Marathon starts on the Staten Island side of the Verrazano Narrows bridge.
4. Ganter Bridge
This bridge was also designed by Christian Menn. It is located in Switzerland and is considered an extradosed bridge. This means that both cable stays and a prestressed box girder deck are used. The cable stays are hidden with the concrete, which was an aesthetic choice by Menn. Given the scale of the mountains and houses in the photo, one can see the majestic height and beauty of the bridge. Structurally, the mountains in this location are prone to shift around, so the ends of the bridge are actually on rollers that can rotate so the bridge doesn’t collapse. It was constructed using the balanced cantilever method, meaning that the towers were constructed first, and the deck was constructed without support from the ground.
5. Alamillo Bridge
This bridge is located in Seville, Spain and was designed by Santiago Calatrava. It is a cable-stayed bridge with only one tower. The bridge has a loud, brash design that certainly stands out in the location. Spanish bridges such as this propelled structural art into the future, with amazing designs that can only be described as feats of engineering. However, one might argue that the Alamillo bridge was not appropriate for the landscape. Indeed, it cost three times as much as another bridge in the same location (the Barqueta Bridge). The landscape of seville consists of classical architecture and low-rise buildings. The Alamillo bridge can be seen from anywhere in the city. To this end, the bridge is still beautiful but might fit better into a more modern setting.
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