To better understand how buildings collapse in earthquakes, scientists have developed a slow-motion earthquake testing method that uses a massive hydraulic ram to push a building model sideways at speeds 100 times slower than real earthquakes. This allows researchers to observe in detail how the structure responds to the shaking and to identify potential weak points.

In one recent experiment performed by researchers at the University of California, San Diego, a five-story steel frame building model was subjected to a series of simulated earthquakes of increasing intensity. The first few quakes caused only minor damage, such as cracks in the plaster and broken windows. But as the shaking intensified, the building began to sway violently and the cracks grew larger. Eventually, the building collapsed completely.

The slow-motion testing revealed several important insights into how buildings collapse in earthquakes. First, it showed that even moderate earthquakes can cause significant damage to buildings. Second, it showed that the type of structural system used in a building can have a major impact on its performance in an earthquake. In the case of the steel frame building model, the lack of bracing between the columns and beams caused the building to sway excessively and eventually collapse.

The results of this research are helping engineers to design buildings that are more resistant to earthquakes. By understanding how buildings collapse, they can develop new ways to strengthen structures and protect people from injury or death in the event of an earthquake.

Watch the video below to see the slow-motion earthquake testing in action.