Japanese researchers have created an app to predict damage to skyscrapers by long-period ground motion from major earthquakes in distant areas, such as the swaying that hit Tokyo after the 2011 Great East Japan Earthquake.
The app will make predictions by floor and issue them before the swaying starts.
Unlike common earthquake ground motion that shakes buildings near epicenters, long-period ground motion can travel long distances without losing strength and causes tall buildings to sway slowly.
That became more widely known after the March 2011 magnitude 9.0 earthquake, when long-period ground motion caused swaying in the capital some 400 kilometers away.
The app for Android tablets predicts the severity of damage in three categories and instructs people to evacuate or stay inside. It is still in trial and expected to be made publicly available next fiscal year, which starts in April.
The app's developers including Yoshiaki Hisada, a professor at Kogakuin University, are aiming to have it issue warnings to registered users one minute before shaking from an earthquake occurring some 200 kilometers away reaches the building they are in.
"While new skyscrapers rarely sustain damage that would require people to evacuate even if it swings greatly, we want people to assess the situation calmly," Hisada said.
Users need to register the structure of their buildings and which floors they are in for it to issue warnings before the motion hits them. The predictions will be based on data provided by the National Research Institute for Earth Science and Disaster Resilience.