I’d never heard of a “seismic isolation floor” until now. Apparently, there are various mechanisms to isolate a building floor from seismic shocks using a free-floating system of supports, dampeners, and restoratives. The floor on the left of the building in the attached video appears to be moving because the camera was mounted to the wall on the right, which was not seismically isolated and so was actually the location of movement - notice how the workers are able to walk even during this large quake. It is nice to see technology succeed despite the sad circumstances. Below is an image of a typical construction; the link is to a fascinating video of such a construction in action in Sendai in a building that housed (probable really expensive and important) servers during the 2011 Tohoku quake. - William
http://digg.com/video/seismic-floor-earthquake?utm_source=atlasobscura