28.13. Importance of Magnitude and Intensity in Seismic Design Codes

Try these first

1. 1.

   What does magnitude measure in earthquakes?

   Hint

   Think about what happens at the start of an earthquake.

2. 2.

   Name one seismic zone in India.

   Hint

   There are five main zones.

3. 3.

   What does magnitude help to define in seismic design?

   • Damage criteria
   • Design Basis Earthquake (DBE) and Maximum Considered Earthquake (MCE)
   • Structural performance

   Hint

   Consider what building engineers base safety on.

4. 4.

   True or False: Intensity measures the energy of the earthquake.

   • True
   • False

   Hint

   Think about how we describe what we feel during an earthquake.

5. 5.

   Considering an area assessed as Zone IV, calculate the implications of magnitude change from 6.5 to 7.5 for building design specifications.

   Hint

   How might an increase in magnitude change the required structural design?

6. 6.

   Evaluate the influence of local geology on intensity measurements during a seismic event, especially in urban areas.

   Hint

   Reflect on how different soil types can change the building's effective response to earthquakes.