Forces and Loads

What is a Structure?

• A structure is an arrangement of materials that will hold its shape under a load

• A load can be compressive, tensile, or a combination of both

• Large structures such as buildings and bridges have two types of loads:

  • • Dead Load- the weight of the structure itself

    • Live Load- Loads that come and go, such as people, furniture, and cars

Forces that Act on Structures

Tower is a Structure- materials that maintain a shape ( vs decorations, etc.)

Forces that act on structures include tension and compression .

Other forces include torsion (arm twisting), bending (illustrate with sponge), and shear

All structures fail when excessive loads are placed on them.

Engineers need to know when structures will fail- knowledge of failure properties (load limits) is critical

Vocabulary of Forces:

• Load

• Tension

• Compression

• Failure analysis