I went through a few in Japan over the years, most were just "was that a tremor?" And was in the south when the tsunami hit Fukushima in 2011. Worst I experienced first hand was when I was in a waterfront hotel about 40 floors up. Maybe 2 or 3am. Water glass and clock hit the floor and anything on shelves fell out. Quite surreal minutes after the last shock hearing the steel clothes hangers still oscillating in the cupboard. Was about a 5.5 from memory so most Japanese ignored it and went back to sleep despite getting the early warning on phones. Emergency vehicles drove around calling out tsunami warnings and then the all clear.
Mind you in 2011 we were pissing it up at a bar after a bored meeting watching the live feeds from around Tokyo. Mobile coverage was overwhelmed and plenty of worried people for several hours. By pure serendipity we were visiting a project in Kyushu the next few days and flew out of Fukuoka. Met up with a few people who had trained it down to get flights home to the US etc. Some pretty scary stories.
Most luckiest though is there are no Orange bicycle company products in Japan, ground pressure exceeds allowable limits, imagine how much worse it could have been.