The Great Bridge debuted 125 years ago
Richard G. Weingardt, P.E.
One hundred and twenty-five years ago, the world celebrated one of the greatest structural engineering feats in history—the completion of the Great
Richard G. Weingardt, P.E.
One hundred and twenty-five years ago, the world celebrated one of the greatest structural engineering feats in history—the completion of the Great
Bridge, the Brooklyn Bridge, the longest suspension
bridge in the world at the time.
Not only a major engineering accomplishment, this structural masterpiece across New York's East River is one of the most famous and beloved bridges in history. Its graceful spider-web array of wires emanating from its towers captures the imagination. Its artistic structure has become a familiar part of the American popular culture, celebrated by artists, poets, writers, and photographers. Walking across its span.......................................r
Not only a major engineering accomplishment, this structural masterpiece across New York's East River is one of the most famous and beloved bridges in history. Its graceful spider-web array of wires emanating from its towers captures the imagination. Its artistic structure has become a familiar part of the American popular culture, celebrated by artists, poets, writers, and photographers. Walking across its span.......................................r
The Great Bridge debuted 125 years ago
Richard G. Weingardt, P.E.
One hundred and twenty-five years ago, the world celebrated one of the greatest structural engineering feats in history—the completion of the GreatBridge, the Brooklyn Bridge, the longest suspension bridge in the world at the time.
Not only a major engineering accomplishment, this structural masterpiece across New York's East River is one of the most famous and beloved bridges in history. Its graceful spider-web array of wires emanating from its towers captures the imagination. Its artistic structure has become a familiar part of the American popular culture, celebrated by artists, poets, writers, and photographers. Walking across its span or seeing it illuminated at night is an experience of a lifetime.
The Great Bridge's 1,596-foot (283-meter) center span was unheard of in its day. Many were skeptical of the bridge's structural stability, load-carrying capacity, and ability to handle aerodynamic forces. The latter was a major concern after the collapse, due to high winds, of two other highly celebrated suspension bridges—Charles Ellet's Wheeling Bridge over the Ohio River and the Bridge of Constance across the Seine. But Brooklyn's design was more refined.
Even though the Brooklyn Bridge was the brainchild of German-born-and-educated John Roebling (1806-1869), its design and construction was totally an American accomplishment. By the time the bridge was planned, Roebling had long been a U.S. citizen and successful businessman. He had already designed several noteworthy American suspension bridges, including the Covington-Cincinnati Bridge, the Delaware Aqueduct, and the Niagara Bridge.
The Brooklyn Bridge's masterful design touted several firsts and records. For one, it was the first time galvanized steel wire had been used in a bridge. Its four main cables were almost 16 inches in diameter (each comprising 19 strands of 286 wires) with a total length of 3,578 feet from anchorage to anchorage. Roebling had intended the cables to be thinner, but when it was discovered a supplier was including faulty wire in its cables, rather than having the substandard wire removed, the number of wires in the cables were increased.
The bridge's two Gothic-style, masonry, cable-support towers were built to a height of 277 feet when most big buildings around it were 50 to 70 feet high. The massive pneumatic caissons supporting the towers were the largest in America at the time, though one of the Eads Bridge caissons was deeper.
Constructing the Brooklyn Bridge took a heavy toll on the Roebling family. Just as construction began in 1869, a ferryboat ran into the dock John was standing on, crushing his left foot. Tetanus set in and his foot was amputated, but to no avail. He died shortly after. His 32-year-old son Washington Roebling (1837-1926) took over as the Brooklyn's chief engineer. He had already assisted his father in developing the design and had spent time in Europe studying the latest pneumatic caisson technologies.
Washington completed the bridge's final design and drawings and supervised its construction, often going deep under the river's surface to oversee caisson work. In doing so, he contracted the deadly diver's sickness, "bends disease." It left him partially paralyzed and unable to speak clearly. He was confined to overseeing the construction from the window of his house overlooking the site. He communicated by writing and through his wife Emily Warren Roebling (1843-1903), who essentially became his assistant and chief construction engineer for the project. Many call Emily the "silent builder" of the Great Bridge.
It is appropriate for the U.S. structural engineering community and the public to acknowledge this great engineering accomplishment by the Roeblings. But it begs the question, what are the outstanding structural engineering achievements of today? How are they—and the engineers responsible for them—being honored publicly?
Oh, it's wonderful that engineering groups regularly give out awards for such feats, but no one else knows about them. Many structural engineering achievements today—small and gigantic—match the greatness of the Brooklyn Bridge, but rarely do they receive public adulation or capture the media's attention. Why not? And what can we do to correct that? Send me your ideas.
Richard Weingardt, P.E., is CEO and chairman of Richard Weingardt Consultants, Inc., a Denver-based structural engineering firm. He can be reached via e-mail at rweingardt@gostructural.com.
Richard G. Weingardt, P.E.
One hundred and twenty-five years ago, the world celebrated one of the greatest structural engineering feats in history—the completion of the Great
Bridge, the Brooklyn Bridge, the longest suspension bridge in the world at the time.Not only a major engineering accomplishment, this structural masterpiece across New York's East River is one of the most famous and beloved bridges in history. Its graceful spider-web array of wires emanating from its towers captures the imagination. Its artistic structure has become a familiar part of the American popular culture, celebrated by artists, poets, writers, and photographers. Walking across its span or seeing it illuminated at night is an experience of a lifetime.
The Great Bridge's 1,596-foot (283-meter) center span was unheard of in its day. Many were skeptical of the bridge's structural stability, load-carrying capacity, and ability to handle aerodynamic forces. The latter was a major concern after the collapse, due to high winds, of two other highly celebrated suspension bridges—Charles Ellet's Wheeling Bridge over the Ohio River and the Bridge of Constance across the Seine. But Brooklyn's design was more refined.
Even though the Brooklyn Bridge was the brainchild of German-born-and-educated John Roebling (1806-1869), its design and construction was totally an American accomplishment. By the time the bridge was planned, Roebling had long been a U.S. citizen and successful businessman. He had already designed several noteworthy American suspension bridges, including the Covington-Cincinnati Bridge, the Delaware Aqueduct, and the Niagara Bridge.
The Brooklyn Bridge's masterful design touted several firsts and records. For one, it was the first time galvanized steel wire had been used in a bridge. Its four main cables were almost 16 inches in diameter (each comprising 19 strands of 286 wires) with a total length of 3,578 feet from anchorage to anchorage. Roebling had intended the cables to be thinner, but when it was discovered a supplier was including faulty wire in its cables, rather than having the substandard wire removed, the number of wires in the cables were increased.
The bridge's two Gothic-style, masonry, cable-support towers were built to a height of 277 feet when most big buildings around it were 50 to 70 feet high. The massive pneumatic caissons supporting the towers were the largest in America at the time, though one of the Eads Bridge caissons was deeper.
Constructing the Brooklyn Bridge took a heavy toll on the Roebling family. Just as construction began in 1869, a ferryboat ran into the dock John was standing on, crushing his left foot. Tetanus set in and his foot was amputated, but to no avail. He died shortly after. His 32-year-old son Washington Roebling (1837-1926) took over as the Brooklyn's chief engineer. He had already assisted his father in developing the design and had spent time in Europe studying the latest pneumatic caisson technologies.
Washington completed the bridge's final design and drawings and supervised its construction, often going deep under the river's surface to oversee caisson work. In doing so, he contracted the deadly diver's sickness, "bends disease." It left him partially paralyzed and unable to speak clearly. He was confined to overseeing the construction from the window of his house overlooking the site. He communicated by writing and through his wife Emily Warren Roebling (1843-1903), who essentially became his assistant and chief construction engineer for the project. Many call Emily the "silent builder" of the Great Bridge.
It is appropriate for the U.S. structural engineering community and the public to acknowledge this great engineering accomplishment by the Roeblings. But it begs the question, what are the outstanding structural engineering achievements of today? How are they—and the engineers responsible for them—being honored publicly?
Oh, it's wonderful that engineering groups regularly give out awards for such feats, but no one else knows about them. Many structural engineering achievements today—small and gigantic—match the greatness of the Brooklyn Bridge, but rarely do they receive public adulation or capture the media's attention. Why not? And what can we do to correct that? Send me your ideas.
Richard Weingardt, P.E., is CEO and chairman of Richard Weingardt Consultants, Inc., a Denver-based structural engineering firm. He can be reached via e-mail at rweingardt@gostructural.com.
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