What the

1
What the
?!?

• Understanding Boundary Conditions for Statics and
  Mechanics Problems
• Ben Schafer
• 28 September 2000

2
Typical Statics and Mechanics Cartoons
simply supported beam
fixed beam
3 hinged arch
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Pinned or hinged
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1930 Tyne Bridge in Newcastle England530 span 2
hinged arch bridge
G B-37
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Hinge Detail (or pin) 1 diameter pin - 8 1/2
long
G B-38
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Grosvenor Bridge over the Thames in London Two
hinged arch
G B-39
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hinge detail
G B-40
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Rollers and Rockers
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Potomac River Highway Bridge in DC
G A-28
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detail of roller support
G A-29
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Rhine River Bridge in Frankfurt Germany Rebuilt
after WWII to mimic its destroyed predecessor.
G D-35
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Roller detailCan you see the makings of the
roller cartoon?
G D-36
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Fixed
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Henry Hudson Bridge at juncture of Harlem and
Hudson River in NY. Fixed arch - double deck
G B-64
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detail of fixed bearing
G B-65
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Bringing it all together 1Lift Bridge
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Lift Bridge in the Sacramento River Delta near
Rio Vista CA
G D-8
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Lift bridge in use
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Explicit - internal hinge joint detail
G D-15
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fixed hinge bearing
G D-16
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rocker bearing
G D-17
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Bringing it all together 2Arches over Harlem
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White High Bridge - 3 pinBlue Alexander
Hamilton - fixedRed Washington Traffic - 2 pin
G B 27
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White High Bridge, central pin detail
G B-28
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Blue Alexander Hamilton - fixed support
G B-63
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Red Washington Traffic - Pins
G B-34