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The original Tacoma Narrows Bridge opened on July 1, 1940. It received its nickname "Galloping Gertie" because of the vertical movement of the deck observed by construction workers during windy conditions. The bridge became known for its pitching deck, and collapsed into Puget Sound the morning of November 7, 1940, under high wind conditions. Engineering issues as well as the United States' involvement in World War II postponed plans to replace the bridge for several years; the replacement bridge was opened on October 14, 1950.
By 1990, population growth and development on the Kitsap Peninsula caused traffic on the bridge to exceed its design capacity; as a result, in 1998 Washington voters approved a measure to support building a parallel bridge. After a series of protests and court battles, construction began in 2002 and the new bridge opened to carry eastbound traffic on July 15, 2007, while the 1950 bridge was reconfigured to carry westbound traffic.
At the time of their construction, both the 1940 and 1950 bridges were the third-longest suspension bridges in the world in terms of main span length, behind the Golden Gate Bridge and George Washington Bridge. The 1950 and 2007 bridges are now the fifth-longest suspension bridge spans in the United States, and the 38th-longest in the world.[citation needed]
Tolls were charged on the bridge for the entire four-month service life of the original span, as well as the first 15 years of the 1950 bridge. In 1965, the bridge's construction bonds plus interest were paid off, and the state ceased toll collection on the bridge. Over 40 years later, tolls were reinstated as part of the financing of the twin span, and are presently collected only from vehicles traveling eastbound.
The desire for the construction of a bridge in this location dates back to 1889 with a Northern Pacific Railway proposal for a trestle, but concerted efforts began in the mid-1920s. In 1937, the Washington State legislature created the Washington State Toll Bridge Authority and appropriated $5,000 to study the request by Tacoma and Pierce County for a bridge over the Narrows. The bridge was designed by Leon Moisseiff.
The first Tacoma Narrows Bridge opened to traffic on July 1, 1940. Its main span collapsed into the Tacoma Narrows four months later on November 7, 1940, at 11:00 AM (Pacific time) as a result of aeroelastic flutter caused by a 42 mph (68 km/h) wind. The bridge collapse had lasting effects on science and engineering. In many undergraduate physics texts the event is presented as an example of elementary forced resonance with the wind providing an external periodic frequency that matched the natural structural frequency, even though the real cause of the bridge's failure was aeroelastic flutter. A contributing factor was its solid sides, not allowing wind to pass through the bridge's deck. Thus its design allowed the bridge to catch the wind and sway, which ultimately took it down. Its failure also boosted research in the field of bridge aerodynamics/aeroelastics, fields which have influenced the designs of all the world's great long-span bridges built since 1940.
No human life was lost in the collapse of the bridge. The only fatality was a cocker spaniel who perished after it was abandoned in a car on the bridge by its owner, Leonard Coatsworth. Professor Frederick Burt Farquharson (an engineer from U. Washington who had been involved in the design of the bridge) tried to rescue it, but was bitten by the terrified dog when he attempted to remove it. The collapse of the bridge was recorded on 16 mm film by Barney Elliott, owner of a local camera shop, and shows Farquharson leaving the bridge after trying to rescue the dog and making observations in the middle of the bridge. In 1998, The Tacoma Narrows Bridge Collapse was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant". This footage is still shown to engineering, architecture, and physics students as a cautionary tale.
Dismantling of the towers and side spans—which survived the collapse of the main span but were damaged beyond repair—began shortly after the collapse and continued into May 1943. The United States' participation in World War II as well as engineering and finance issues delayed plans to replace the bridge.
The current westbound bridge was designed and rebuilt with open trusses, stiffening struts and openings in the roadway to let wind through. It opened on October 14, 1950, and is 5,979 feet (1822 m) long — 40 feet (12 m) longer than the first bridge, Galloping Gertie. Local residents nicknamed the new bridge Sturdy Gertie, as the oscillations that plagued the previous design had been eliminated. This bridge along with its new parallel eastbound bridge are currently the fifth-longest suspension bridges in the United States.
When built, the westbound bridge was the third-longest suspension bridge span in the world.Like other modern suspension bridges, the westbound bridge was built with steel plates that feature sharp entry edges rather than the flat plate sides used in the original Tacoma Narrows Bridge (see the suspension bridge article for an example).
The bridge was designed to handle 60,000 vehicles a day. It carried both westbound and eastbound traffic until the eastbound bridge opened on July 15, 2007
In 1998, voters in several Washington counties approved an advisory measure to create a second Narrows span. Construction of the new span, which carries eastbound traffic parallel to the current bridge, began on October 4, 2002, and was completed in July 2007. The Washington State Department of Transportation collects a toll before entering the eastbound span, at $4.50 for Good To Go! account holders with in-vehicle transponders, and a $5.50 toll for cash/credit card customers. The existing span had been free of tolls since 1965. The new bridge marks the first installation of the new Good To Go! electronic toll collection system.
Miles telephoned Clark Eldridge to tell him to come to the bridge because it was "about to go."
Gertie begins torsional oscillation shortly after 10 a.m. WSDOT
Gertie twisting
GHPHSM, Bashford 2784
10:03 a.m. first section of concrete from roadway splashes into the Narrows below Galloping Gertie WSDOT
10:03 a.m. first section of concrete from roadway splashes into the Narrows below Galloping Gertie
WSDOT
Around 10:15 a.m., Clark Eldridge arrived at the bridge. He saw it "swaying wildly" with the bottom side visible as it tilted. Several people were struggling off the roadway at the east end. He joined Farquharson at the East Tower to discuss the situation. They returned to the east anchorage to warn people to stay off the span.
Around 10:30 a.m., a large chunk of concrete dropped out and fell from a section on the west side of the center span. On the west end workmen backed a truck out onto the rolling bridge to rescue Ruby Jacox and Walter Hagen.
On the east end, Farquharson continued taking photos. Clifford, Bashford, and Brintnall arrived. Clifford began taking photographs and ventured onto the span, joining Farquharson. Now, another cameraman, Barney Elliott from The Camera Shop, stood on the twisting bridge taking motion picture footage.
For a short period, the wind subsided and the span steadied itself. Photographer Howard Clifford ventured onto the center span to save Tubby, but had to turn back. He stopped at the East Tower and resumed taking photos.
Farquarson
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Farquharson continued his observations, taking photographs and motion pictures from the vicinity of the East Tower. He still believed that the bridge would settle down.
About 10:55 a.m., some 6 minutes before the bridge began to fail, Farquharson (who loved dogs) decided to try to save Tubby. But, when he reached into the car, the terrified dog bit his finger. The professor stumbled back to the East Tower just in time.
By 11:00 a.m. the extreme twisting waves of the roadway, magnified by the aerodynamic effect of wind on the sides of the bridge, began to rip the span. Huge chunks of concrete broke off "like popcorn" (in the words of one witness) and fell into the chilly waters far below. Massive steel girders twisted like rubber. Bolts sheered and flew into the wind. Six light poles on the east end broke off like matchsticks. Steel suspender cables snapped with a sound like gun shots, flying into the air "like fishing lines," as Farquharson said.
The strange sounds of the bridge's writhing filled the air. When the tie-down cables failed, the side spans began to work the main cables back and forth. The movement shifted the steel covers where the cables entered the anchorage, producing a metallic shrieking wail. By now, several hundred bystanders stood on the eastern shore of the Narrows. From the bluff, a workman on a pile driver repeatedly tooted his whistle to try to warn the approaching Coast Guard cutter, Atlanta, which passed under the bridge. The shrill whistle blasts mixed with the howl of gusting winds and the grinding and screeching of metal and concrete. The wild noises gave onlookers a sense of dread and impending calamity.
At 11:02, a 600-foot long section of roadway in the eastern half of the center span (the "Gig Harbor quarter point") of the heaving bridge broke free. With a thunderous roar, the massive section wrenched from its cables in a cloud of concrete dust, flipped over, and plummeted 195 feet into Puget Sound. A mighty geyser of foam and spray shot upward over 100 feet. Great sparks from shorting electric wires flew into the air.
Howard Clifford account
Clifford
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Farquharson ran from the East Tower toward the Toll Plaza, covering the 1,100 feet of the side span length as fast as his legs could carry him. He followed the centerline, where he knew there was least motion. Twice, the roadway dropped 60 feet, faster than gravity, then bounced upward, finally settling into a 30-foot deep sag. Just in front of him Howard Clifford ran, fell, and scrambled up the roadway.
Last Man on the Bridge and Other Adventures
Weird Fact #23
Hear Leonard Coatsworth's account
Coatsworth
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Successive deck sections rapidly fell out toward each tower. Coatsworth's car and Tubby followed the plunging roadway into the wind-swept Narrows.
By 11:10 a.m. it was over. The cold waters churned, eddied, and swirled. The heart of Galloping Gertie sank beneath whitecaps, coming to rest on the bottom of Puget Sound.
Huge splash as final section of bridge collapses, 11:10 a.m. on November 7, 1940 TPL 6263
Huge splash as final section of bridge collapses, 11:10 a.m. on November 7, 1940
Tacoma Public Library copyright information
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