BY: KAREN CUMMINGS
Since 1890, when famed American explorer and Governor William Gilpin fi rst introduced the idea of linking the continents of America and Asia together through rail, people have dreamed of uniting the world by land. But it wasn’t until 1958, when a Chinese born engineer by the name of Tung-Yen Lin revealed design solutions that made the feat of bridging the Bering Strait structurally possible, that people dared to dream it could become a reality.
ENGINEERING THE “IMPOSSIBLE”
Tung-Yen (T.Y.) Lin was the fourth child of 11 children born in Fazhou, China to a justice of the ROC Supreme Court. He began his training in engineering at the tender age of 14 and earned his master’s in civil engineering from the University of California, Berkeley, in 1933. After working in China for the Ministry of Railways where he was responsible for constructing over 1,000 bridges, Lin returned to Berkeley as faculty in 1946. It was at Berkeley where Lin took French engineer Eugene Freyssinet’s original prestressed concrete designs and began to tweak them. Lin worked on solving two problems; concrete’s
natural pre-disposition for tensile weakness and steel’s propensity to become brittle. By combining the two, “prestressed” concrete was resistant to compression, much stronger, and able to endure the tests of both time and Mother Nature. Often referred to as “Mr. Prestressed Concrete”, Lin
founded T.Y. Lin International in 1954 and began an illustrious and decorated career conceiving, designing and
MISR Satellite photo of Bering Strait
constructing some of the world’s best airports, buildings, bridges, roads, ports and railways. Just a few you may have heard of include; T e 1800 Pacifi c Building in San Francisco, San Fran’s Moscone Convention Centre (250,000 sq. ft. column-free exhibit hall), the Kuan Du Bridge in Taiwan and the Hoover Dam ByPass Bridge. But prestressed concrete wasn’t just functional to
T.Y. Lin – its ability to create unique shapes allowed him to create things of beauty. Lin said, “T e engineering approach should be a global vision of the bridge. To fi t the environment and to express the structural forces and moments, and nature itself.” To T.Y. Lin, the Bering and Gibraltar Straits must
have been “the holy grails” of his profession – challenging him both intellectually and philosophically. Lin was technically certain enough in 1986 that the feat of bridging the Bering Strait could be accomplished to hand over a 16-page building plan to President Ronald Reagan while receiving the National Medal of Science Award.
With the Seward Peninsula of Alaska to the east, and Chukotskiy Poluostrovof Siberia to the west, the Bering Strait separates the United States and the Russian Federation by only 90 kilometers. It is named for Danish explorer Vitus Bering, who spotted the Alaskan mainland in 1741 while leading an expedition of Russian sailors. This view of the region was captured by MISR’s vertical-viewing (nadir) camera on August 18, 2000 during Terra orbit 3562.
28 MARCH-APRIL 2012 WIRE ROPE EXCHANGE
Federal Highway Administration, Central Federal Lands Highway Division
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