brick,mud,wood
Concrete and steel .
some materials used in bridges are concrete, steal, metal [may rust and fall if metal ] the first bridge may or may not have been made of wood
depends on the bridge type really. most are steel and concrete.
Usually concrete. Romans invented concrete.
The most common materials used in bridge building are generally steel or concrete for larger bridges, and stone or wood for smaller bridges.
It can be made out of any material but the has to have beams on it for obvious reasons. Hope this helped!
The designs that are used to build bridges are designs that can keep them stable , working and that won't be dangerous also designs that amaze people.
The Romans used the arch to build large buildings and bridges.
the materials used to build the truning torso are, medal frames . aluminum wood , glass and i dont know , just those ,,, ^^^
Steel is the most common, especially for suspension bridges. Concrete is used for lower bridges (and where little shifting will occur) because it is more resistant to the elements.
Steel and concrete.
bridges are colapsing because they are old and the material that the people used is old or the people that built it did not build it right