Bridges: history, forces, and types

Bridges:History, Forces, & Types

History

• The first bridges consisted of fallen logs over rivers.

History• The development of rope allowed

people to build primitive suspension bridges.

• You can see examples of this type of bridge in many movies.

I guarantee you have all been on one

• Isn’t this the same thing?

Who Designs them?• A Civil Engineer is a

person who designs bridges

• Civil Engineers must be strong in math and science to be able to properly design a bridge

Forces• Tension: A force that tries to

stretch material and pull it apart

• Compression: A force that tries to push or squeeze material together

More Forces• Shear: A force that tries to make

materials tear and slide by each other

• Torsion: A Force that tries to twist and bend materials

What happens when there is too much force on a bridge?

Beam Bridge

Compression

Tension

Truss Bridge

Compression

Tension

Arch Bridge

Compression

Tension

Suspension Bridge

Compression

Tension

Cable-Stay Bridge

Compression

Tension

Review