Controlled Rocking Buildings

A major problem with current standards for building structures in the US is that they normally only account for vertical and normal forces. The downside to this is that earthquakes cause horizontal and lateral forces. Most buildings are simply made strong enough to prevent a collapse or loss of life, but accept minor building damage. In areas as North Dakota, the minute chance of an earthquake occurring makes it unnecessary to worry about such precautions. In places like California though, earthquakes can lead to huge building repair costs following frequent earthquakes. A recent study at Case Western Reserve University has produced results of a new technology that could help prevent even the majority of minor damage to structures in areas of heavy seismic activity.

Rocking Technology

Michael Pollino

Although not the inventor of the idea, Michael Pollino, an assistant professor of civil engineering at Case Western Reserve University, has created a program that allows him to compare their performance versus current earthquake standards. The technology can be a bit difficult to understand, but the theory behind the idea is relatively simple. Imagine you are waist deep in a jar of maple syrup, and somebody begins to shake the jar. The jar and syrup will move, but you will move less and more slowly as the syrup dissipates the lateral energy.

With that concept in mind, think of the foundations of a building. Usually they are steel or reinforced concrete beams with a concrete base. The idea is that instead of using a concrete base, the bottoms of the columns would be set in a heavily viscous liquid. Steel-based frames would be used to act as springs to pull the building back towards a homeostatic position. The combination of both of these technologies results in a building that will slightly rock when hit with lateral forces. 

Future Applications

Although this technology is not being practices in the field at the current time, many researchers are beginning to support the concept. Pollino and his colleagues hope to form a technical committee that will attempt to bring this concept out into the design world. There are still many details to work out, but his group is confident is the potential of this technology.

Concept drawing of a rocking building

The idea of rocking buildings could revolutionize the design of future buildings in California and other areas where earthquakes frequently occur. Unfortunately this concept does nothing to help currently standing buildings. Since the rocking device will be put on the base columns, this needs to be done prior to construction of the building. I believe an imperative future application of this technology should be a way to adapt is to existing structures. New buildings would be fine during earthquakes, but damage to nearby structures could result in damage to these new buildings anyway.