Title: A brief study of bridges
1A brief study of bridges
2We build different bridges for different needs
3Covered Bridge
4Covered Bridges
In the 18th and 19th century many bridges were
covered
5Covered Bridges
Why do you think these bridges were covered?
6Covered Bridges
Some say it was for protection from a sudden storm
7Covered Bridges
Some say to keep horses from shying at the sight
of rippling water
8Covered Bridges
Some say to provided a romantic setting for a hug
or kiss
9Covered Bridges
However
10Covered Bridges
The real reason was to protect the timber from
the effects of rain and snow
11Beam Bridge
12Beam Bridge
The simplest and least expensive
Beam Sometimes called a girder
13Beam Bridge
Can be made of steel
14Beam Bridge
Concrete
15Beam Bridge
or even wood
16Beam Bridge
Not the best for long or high spans
17Suspension Bridge
18Suspension Bridge
Better for Long spans
More Majestic
19First suspension bridge in America Newburyport,
Mass.
Built around 1900
20Golden Gate Bridge Perhaps the most famous bridge
in the world
Why is it called the Golden Gate?
21Golden Gate Bridge Perhaps the most famous bridge
in the world
It spans the Golden Gate Strait
22The worlds 10 longest spans are all suspension
bridges
23Arch Bridge
24Arch Bridge
Very strong
Can last a very long time
25Arch Bridge
This is Pont du Gard a 2000 year old Roman
aqueduct
26Arch bridge
This is a bridge built so that a stream of water
could cross a stream of water
27Cable Stayed Bridge
28Cable Stayed bridge
Long spans
Elegant structure
29Sunshine Skyway BridgeSt. Petersburg, FL
Requires Less labor
Requires less material
30Sunshine Skyway BridgeSt. Petersburg, FL
Similar to Clark bridge in Alton, IL
31Lift Bridge
32Lifting Bridge
Do you know the name of this bridge?
33Lifting Bridge
It is not London Bridge.
34Lifting Bridge
Tower Bridge
It is over 100 years old
35Truss Bridge
36Truss Bridge
A truss can support from above
37Truss Bridge
A truss can also support from below
38Truss Bridge
What do you know about this bridge?
39Eads BridgeSt. Louis, MO
Completed in 1874
American masterpiece
40A quick review
41Covered Bridges
Makes use of local building supplies
42Covered Bridges
Interior truss makes it stronger than wood beam
bridge
43Covered Bridges
Covering the timbers makes them last longer
44Beam Bridge
Easiest to build
Least expensive design
45Cable Stay Bridge
Less expensive to build than suspension bridges
46Cable Stay Bridges
Uses less material than suspension bridge
47Cable Stay Bridges
They look cool!
48Cable Stay Bridges
Requires the use of more modern materials
49Suspension Bridges
Longest unsupported spans
50Suspension Bridges
They look pretty cool too!
51Arched Bridges
Strong
Durable
Ancient/low tech building materials
Labor intensive
52Truss Bridge
Stronger than beam bridge
Think Vectors!
53Truss Bridge
Can bridge longer unsupported spans than a beam
bridge
54Lifting Bridge
Blocks trafic
55Lifting Bridge
Allows the passage of ships
56Lifting Bridge
Rather expensive
Subject to mechanical breakdown
57Many different bridges for many different jobs
58See these websites for more information on bridge
design
http//www.howstuffworks.com/bridge.htm http//ww
w.pbs.org/wgbh/nova/bridge/ http//myron.sjsu.edu
/romeweb/engineer/art2.htm http//www.bardaglea.o
rg.uk/bridges/welcome.html http//education.sdsc.
edu/enrich/downloadables/bridges.pdf http//www.t
fhrc.gov/pubrds/summer95/p95su23.htm