Building with triangles
The triangle is indispensable in building. Its use and strength relies on the fact that
made it indispensable in surveying – a triangle is rigid. You can push a square or
rectangle out of shape but not a triangle. The truss used in building is the joining
together of triangles, and is seen as the component in roofs. One breakthrough
occurred in the building of bridges.
A Warren girder bridge
A Warren truss can take a heavy loading compared to its weight. It was patented in
1848 by James Warren and the first bridge designed in this way was constructed at
London Bridge Station two years later. The use of equilateral triangles proved more
reliable than similar designs based on the isosceles triangles, the triangles where only
two sides are required to be equal.
It can be applied to any triangle and we don’t even have to know any angles.
The symbol s stands for one half of the perimeter of the triangle whose sides are
of length a, b and c. For example, if a triangle has sides 13, 14 and 15, the
perimeter is 13 + 14 + 15 = 42, so that s = 21. Completing the calculation,
. The triangle is a familiar object, whether to
children playing with simple shapes or researchers dealing on a day-to-day basis
with the triangle inequality in abstract mathematics. Trigonometry is the basis for
making calculations about triangles and the sine, cosine and tangent functions
are the tools for describing them, enabling us to make accurate calculations for
practical applications. The triangle has received much attention but it is surprising
that so much is waiting to be discovered about three lines forming such a basic
figure.