Forces Lab |
Materials Lab |
Loads Lab |
This lab simplifies the real-life forces and actions that affect structures, in order to illustrate key concepts.
Forces act on big structures in many ways.
Click on one of the actions at left to explore the
forces at work and to see real-life examples.
Compression is a force that squeezes a
material together. When a material is in
compression, it tends to become shorter.
The lower columns of a skyscraper are squeezed by the heavy weight above them. This squeezing force is called compression.
Tension is a force that stretches a
material apart. When a material is in
tension, it tends to become longer.
The weight of the roadway and all the cars traveling on it pull on the vertical cables in this suspension bridge. The cables are in tension.
When a straight material becomes curved,
one side squeezes together and the other side
stretches apart. This action is called bending.
The top side of the metal bar is pulled apart in tension, and the bottom side is squeezed together in compression. This combination of opposite forces produces an action called bending.
Shear is a force that causes parts of a material to slide past one another in opposite directions. Ý
During an earthquake, parts of this roadway slid in opposite directions. This sliding action is called shear.
Torsion is an action that twists a material.
In 1940, the Tacoma Narrows Bridge twisted violently in strong winds and collapsed. The twisting force that tore this bridge in half is called torsion. Ý
Flash version of this lab