Buildings can be designed to withstand earthquakes — why aren’t we building more of them?
When the shaking started at 5:46 a.m., Yasuhisa Itakura, an architect at a big Japanese construction company in Kobe, was sitting at his desk finishing a report he had toiled over all night. His office swayed, but the books stayed on their shelves and nothing fell off his desk.
“I thought to myself, this earthquake is not that big,” Itakura said.
It was, in fact, catastrophic. The Great Hanshin earthquake of Jan. 17, 1995, killed more than 6,000 people in and around the industrial port city.
Itakura had been cushioned from the violence of the earthquake because his three-story office building was sitting on an experimental foundation made from rubber — an early version of an engineering technique called base isolation.
The technique that protected Itakura’s building is used in roughly 9,000 structures in Japan today, up from just two dozen at the time of the Kobe earthquake. Thousands of other buildings in the country have been fitted with shock-absorbing devices that can greatly reduce damage and prevent collapse.
Chile, China, Italy, Mexico, Peru, Turkey and other countries vulnerable to earthquakes have adopted the technologies to varying degrees.
But with notable exceptions, including Apple’s new headquarters in Silicon Valley, the innovations have been used only sparingly in the United States. Seismic safety advocates describe this as a missed opportunity to save billions of dollars in reconstruction costs after the inevitable Big One strikes.
Earthquakes are of course natural phenomena. But the amount of damage they cause is a function of decisions made by politicians, engineers and business executives. Japan and the United States, two of the world’s most technologically advanced countries, have the same problem — how to protect people and society from earthquakes — and yet they have responded in very different ways.
Japan, through both government mandates and its engineering culture, builds stronger structures capable of withstanding earthquakes and being used immediately afterward. The United States sets a minimum and less protective standard with the understanding that many buildings will be badly damaged.
The two approaches reflect different attitudes toward risk, the role of government and collective social responsibility. Analogous to America’s debate over health insurance, the U.S. philosophy has been to make more resilient buildings an individual choice, not a government mandate.
“Do we want to be more like Japan and are we willing to pay the price?” said Joyce Fuss, president of the Structural Engineers Association of California. “A lot of people would say ‘no’ and maybe some people would say ‘yes.’”
Inherent in the U.S. approach to seismic engineering is a risk calculation: Many American engineers operate on the assumption that a building, which might be used for 50 years before it is torn down and replaced with a new one, has a relatively small chance of being hit by a huge earthquake.
“If you spend the money today and the earthquake happens tomorrow, then congratulations, you’ve done a good job,” said Ron Hamburger, an American structural engineer who is perhaps the leading authority on the building code. “But the fact is, truly significant damaging earthquakes will affect a place like San Francisco or Los Angeles maybe once every 100 to 200 years.”
“How lucky do you feel?” he added.