William Parnell, a mathematician from the University of Manchester in England, thinks he might have a way to make buildings immune to the devastating effects of earthquakes.
As detailed in this month’s issue of Smithsonian magazine, Parnell has invented an “elastodynamic cloak” that will supposedly leave buildings almost entirely untouched by an earthquake’s shock waves. The method involves encasing a structure’s base in a specialized rubber that will divert the waves completely, making buildings "invisible" to earthquakes.
Zeeya Merali describes the concept behind the technique:
Parnell’s “elastodynamic cloak,” which engineers have just started testing, builds on a familiar concept: Waves headed directly for an object can be diffracted or bent so they miss it entirely. In the best-known example, scientists make objects appear invisible by encasing them within substances that have been engineered to alter the trajectory of light. When light waves pass through the cloak, they are channeled like water flowing around a rock. To an observer downstream, it appears that the light moved along a straight line, as if the object was not there.
When it comes to earthquakes, Parnell believes he can use the same method to channel zigzagging Love waves around an object by placing it in the exact center of an underground rubber encasement. If the rubber is stretched in a specific way, it may be able to mimic the process of light-cloaking materials.
While engineers already use rubber shock absorbers to protect buildings against earthquakes, using an elastodynamic cloak could prevent structures from feeling Love waves entirely. If surrounding an entire building with rubber rings proves to be too costly, Parnell says the cloaks could be placed only around important electrical equipment.
The cloak will soon be tested by engineers at the Industrial Research Limited in New Zealand.
Image: Seattle Municipal Archives/Flickr