15.9. Influence of Mass and Stiffness Distribution

Try these first

1. 1.

   What happens to mode shapes when mass distribution is uneven?

   Hint

   Think about how uneven weight affects movement.

2. 2.

   Define stiffness distribution in your own words.

   Hint

   Consider how different materials contribute to a structure’s stiffness.

3. 3.

   What is the impact of uneven mass distribution in a structure?

   • Localized vibrations
   • Even vibrations
   • No impact

   Hint

   Think about how weight affects movement.

4. 4.

   True or False: Symmetrical stiffness distribution results in simpler mode shapes.

   • True
   • False

   Hint

   Recall what symmetry means in structural design.

5. 5.

   A building has a heavy machine on its third floor, affecting its overall mass distribution. Predict how this will influence its mode shapes during an earthquake.

   Hint

   Think about how the added weight shifts the focus of vibrations.

6. 6.

   Propose a design strategy for a building in an earthquake-prone area that mitigates the effects of uneven mass and stiffness distribution.

   Hint

   How can you engineer solutions that enhance stability?