Technology
Photocopy nº____
Bridges
Complete this photocopy with the information at
http://www.pbs.org/wgbh/buildingbig/bridge/basics.html
1. Beam bridge
The beam bridge consists of a horizontal beam supported at
each end by piers. The beam bridge is very limited in the
distance it can span.
Vocabulary: Beam:
Piers:
Span:
Exercise 1) On the following picture mark where are the Beam,the piers, and the
span of the bridge:
Exercise 2) What is the usual maximum span of a beam bridge in meters? (1 feet =
0.3 meters)
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Forces on a beam bridge
Exercise 3) Click on “Sneak a peek at the forces that act on beam bridges! “ and
draw and name the forces on a beam bridge
When something pushes down on the beam, the beam bends. Its
top edge is pushed together (compression), and its bottom
edge is pulled apart (tension).
Click on
2. Truss bridge
Exercise 4)In what does a a truss bridge consists?
Exercise 5)What is a truss bridge commonly made of?
Vocabulary: Truss:
Bars:
Span:
Exercise 6) The bridge in the picture is a special kind of truss bridge, how are
they called?
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Forces on a truss bridge
Exercise 7) Click on “Check out the forces that act on truss bridges! “ and
draw and name the forces on a truss bridge
Exercise 8) Do the bars of a truss bridge bend? Can it span farther or shorter
than a beam bridge?
Click on
3. Arch bridge
Exercise 9) What were roman bridges usually made of? What are, today, most
arch bridges made of ?
Exercise 10) How long can arch bridges span up to? (1 feet = 0.3 meters)
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Forces on an arch bridge
Exercise 11) Click on “Catch a glimpse of the forces that act on arch bridges!
and draw and name the forces on a arch bridge
Exercise 12) Vocabulary
Arch bridge is a semicircular structure with supports or a__u______s on each
end. Mark the semicircular structure and the supports on the drawing above.
Arch bridges are always under compression. The force of
compression is pushed outward along the curve of the arch
toward the abutments.
Click on
4. Suspension bridge
A suspension bridge is one where the deck is suspended from cables (or
ropes or chains). A suspenssion bridge can span way farther than any
other type of bridge!
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Exercise 12) How far can a suspension bridge span? (1 feet = 0.3 meters)
Exercise 13) What do suspension bridges have beneath the roadway/deck?
Why?
Exercise 14) Click on “See how forces act on suspension bridges!” and name
the parts of a suspension bridge:
Exercise 15) What are the cables usually made of?
Forces on a suspension bridge
Exercise 16) Draw and name the forces on a suspension bridge
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Summary exercise
Draw the 4 main types of bridges with its parts and forces:
Name
Drawing
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