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Hængebroers kraftpåvirkning

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Kan I hjælpe mig med at finde en bog (meget gerne flere) om hængebroers kraftpåvirkning? Fordele og ulemper ved brotypen?
På forhånd tak!

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Millennium Bridge var for gyngende og ustabil og blev derfor lukket i næsten to år, for at udbedre dette problem. Jeg har udvalgt nogle passager fra nettet som underbygger dette.

Fra Wikipedia.org: "Londoners nicknamed the bridge the "Wobbly Bridge" after participants in a charity walk on behalf of Save the Children to open the bridge felt an unexpected and, for some, uncomfortable swaying motion on the first two days after the bridge opened. The bridge was closed later that day, and after two days of limited access the bridge was closed for almost two years while modifications were made to eliminate the wobble entirely. It reopened in 2002."

"Unexpected lateral vibration (resonant structural response) caused the bridge to be closed on 12 June 2000 for modifications. Attempts were made to limit the number of people crossing the bridge. This led to long queues and dampened neither public enthusiasm for what was something of a white-knuckle ride, nor the vibrations themselves. The closure of the bridge only two days after opening attracted public criticism of it as another high-profile British Millennium project suffered an embarrassing setback, akin to how many saw the Millennium Dome. The wobble was attributed to an under-researched phenomenon whereby pedestrians crossing a bridge that has a lateral sway have an unconscious tendency to match their footsteps to the sway, thereby exacerbating the sway. The tendency of a suspension bridge to sway when troops march over it in step was well known, which is why troops are required to break step when crossing such a bridge"

Læs også: http://www.londonmillenniumbridge.com/ under fanen 'Challenge'. Der er 6 kapitler og noget video, der på teknisk vis går i dybden med problemet og løsningen.

Citat fra The New York Times, April 21, 2013. The Wobbly Bridge In London

"They nicknamed it the ''wobbly bridge'' when it opened, in 2000, because an engineering miscalculation caused it to sway so badly that people who tried to walk across it grew dizzy and even fell down. But after it was modified and opened again two years later, the Millennium Bridge, a pedestrian-only suspension bridge across the Thames, connecting Bankside on the south side to the City of London financial district on the north, became one of the great walking experiences in a city that might have been invented for strolling."

Jeg har fundet frem til disse bøger som du kan bestille hjem til dit lokale bibliotek via bibliotek.dk

Nielsen, Søren R. K.
Svingningsteori : 7a: specielle konstruktioner: hængebroers dynamik

En terminologisk - fraseologisk undersøgelse af nogle brokonstruktioner med hovedvægt på hængebroer
Kirsten Bech Johannesen

Statisk og dynamisk beregning af hængebroer

Der findes også en del bøger på engelsk om emnet som også kan bestilles hjem. Jeg har udvalgt nogle titler.

Cable-stayed bridges : 40 years of experience worldwide
Holger Svensson

Cable supported bridges : concept and design
Niels J. Gimsing; Christos T. Georgakis

The manual of bridge engineering

30-09-2014

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