The most important variables affecting earthquake damage to buildings are (1) the intensity of the ground shaking, (2) the quality of the engineering design and construction, and (3) the response of the building to the earthquake motion. Engineers do not have much control over the intensity of the ground shaking, but they may be able to recommend alternative locations for buildings. Scientists now know How Earthquakes Affect Buildings and How Buildings Respond to Earthquakes. Find out what building stiffness, damping and ductility have to do with all this! Engineers typically strive for quality in their designs and construction. The main variable that an engineer can control is the response of the building. Check out the IRIS videos on nearly every aspect of seismic science including the Seismic Slinky, and a Building Strength Demo!

Earthquake engineers control the response of a building through many different approaches. Changing the materials and dimensions are probably the easiest ways to vary the response of a building. Watch this video by the Materials Research Society that shows a step in the right direction in the development of earthquake proof houses. But recent innovations such as base isolation, tuned mass dampers, and other energy absorbing devices are significantly improving the response of buildings during earthquakes. Base isolation systems work by de-coupling the motions of the ground from the motions of the building. Tuned mass dampers are installed in buildings to counteract building motions during an earthquake; the mass is tuned such that its oscillations oppose those of the building. Taipei 101, the second tallest building in the world, uses tuned mass dampers. Other types of damping systems and seismic bracing systems that absorb energy by being damaged and then removed are also used in buildings. Visit: How Stuff Works for more great information about protecting buildings from earthquakes.

One of the big challenges that engineers still face is the development of low-cost housing and earthquake engineering systems for poorer communities. The $300 House challenge was initiated in response to the need for affordable housing in poor income areas. Engineers, architects, and contractors continue to strive for affordable housing solutions. National Geographic also has a Safe Houses page with relevant information on materials that could keep you safer in a house located in an earthquake zone. Visit this FEMA Earthquake Safety at Home site and find out more ways you can protect yourself from an earthquake.

For guidance on creating a physical model to experiment with the relationship between building response, mass, and stiffness follow this link!

In May of 2015, Dartmouth will offer a course entitled The Engineering of Structures Around Us. Anyone can register for this free, online course through edX. This course will focus on the response of structures to all types of loading; the final concept in the course will focus on overall building response to earthquakes. Take a look, see if you are interested and sign up!

For more on earthquakes, where they occur and why, visit this TED Ed Lesson!
The effects of earthquakes in California vs China: Andrew Katz