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Modern, fired, clay bricks are formed in one of three processes – so mud, dry press,
or extruded. Normally, brick contains the following ingredients: Silica (sand) – 50% to
60% by weight. Nowadays brick making factories are more mechanized some even
having robots to do the work. Plants where cement, bricks and iron rods are made
make the environment polluted.

Bridges we build
Bridges help us cross a river or a canal.
They can be built over roads and railway
lines and also help in covering the
distances in shorter me, thus, saving a
lot of me. Bridges have always been
constructed to join areas that are not
connected.

One of the simplest forms of bridges is the Beam bridge. It consists of a horizontal
beam which is supported by pillars. It is used to cover short distances. It is just like
pu ng a plank to cross a small pit!

Arch bridge stands strong with the support of the curve of the arch at each end. This
type of bridge has natural strength.

Suspension bridges appear like arch bridges turned upside down. They can cover
more distance than any other type of bridge. Suspension bridges are very flexible.
These bridges are supported by cables, which rest on top of high towers and are
fastened at each end by anchors. Laxman Jhoola in Rishikesh is a suspension bridge.
Most modern bridges are made with steel and concrete.

Fabulous Fact

The Sydney Harbour Bridge is world's widest arch bridge spanning
550 meters of water.

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