Shawn -
Trusses are very frequently used for building things
like towers and bridges. This is because they are constructed out of
triangle shapes. Triangles are a great shape to use for this because a
triangle cannot change shape without changing the length of at least
one side. The sticks used usually are rigid enough to prevent their
lengths from changing. In contrast, a square can flop into a skinnier
shape without changing any side lengths, so its strength depends on
making the joints between the sides strong and rigid, which is not so
easy.
There are a number of different kinds of
because there are many different ways to arrange triangles. Which kind
is best depends on the situation - the shape of the tower, what sort of
stresses it's likely to be under, etc. If you are building a tower for
a project, you can try experimenting with different arrangements of
triangles to see what works best.
-Tamara
(published on 10/22/2007)
