Leon Moisseiff

Leon Solomon Moisseiff ( born November 10, 1872 in Riga, Latvia, † September 3, 1943 in Belmar, New Jersey, United States) was an American bridge engineer who on hanging bridges earned reputation by applying the Deflektionstheorie and by the collapse of his planned Tacoma Narrows Bridge experienced a tragedy.

Life and achievements

Leon Solomon Moisseiff emigrated with his family in 1891 from the belonging to the Russian Empire Latvia to the United States. He studied at Columbia University, where he completed his training in 1895 as a Civil Engineer. At this time he also received the American nationality.

In 1898, he began his career in the Bridge Department of New York City. Under the 1904 Chief Engineer for the new bridge over the East River appointed Othniel Foster Nichols, he drew up a design for a steel suspension bridge, where he developed which goes back to Joseph Melan Deflektionstheorie and first anwandte. This new static analysis method allowed much easier and hence cheaper and faster to-build suspension bridges than before. Opened by 1909 and completed the following year Manhattan Bridge, he acquired a national reputation as an expert on suspension bridges. In 1910 he was appointed Chief Engineer of the Bridge Department. In 1915 he opened his own office as a Consulting Engineer.

He was involved in the planning of many other suspension bridges, such as the

• Benjamin Franklin Bridge (formerly the Delaware River Bridge ) between Philadelphia, Pennsylvania and Camden, New Jersey, as a design engineer;

And as a consulting engineer for the

• Ambassador Bridge between Detroit, Michigan and Windsor, Ontario, Canada;
• George Washington Bridge over the Hudson River in New York City;
• Bronx - Whitestone Bridge over East River in New York City;
• San Francisco - Oakland Bay Bridge;
• Golden Gate Bridge in San Francisco.

When was the first draft of the Tacoma Narrows Bridge by Clark Eldridge considered too expensive, Leon S. Moisseiff offered to create a design for a cheaper bridge. The then he planned and built 1938-1940 Bridge was the third longest suspension bridge and built exceptionally slim and lightweight. Immediately after the opening they showed their vulnerability to wind through vibrations and distortions, which earned her the nickname Galloping Gertie. After only four months, a stormy wind caused such strong vibrations that collapsed the bridge. This was still as good as it does not understand, but great sensational catastrophe ended the career of the 68 -year-old Leon S. Moisseiff. He died three years later in his hometown of Belmar south of New York City.