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. 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. The U.S. philosophy has been to make more resilient buildings an individual choice, not a government mandate.
“In cities like San Francisco, where the median price of a home is well above $1 million, the notion of making construction costs even more expensive is likely to be unpopular, even if the goal is to preserve the city in the long run.
The last major earthquake in the contiguous U.S., which caused $20 billion of damage to the Los Angeles area, was a quarter-century ago.
“The land has been peaceful in America,” said Masayoshi Nakashima, president of the International Association for Earthquake Engineering. “Young generations in particular are not necessarily familiar with the reality of earthquakes.”
The debate over whether to build more resilient buildings in the United States has been held largely out of public view, among engineers and other specialists.
But at stake is whether places like Silicon Valley, Seattle, Salt Lake City, San Francisco or Los Angeles might be forced to shut down after a direct hit - and for how long.
A federal study last year found that a quarter of the buildings in the Bay Area would be significantly damaged after a magnitude-7 earthquake, a disaster that would be compounded by the fact that 9 out of every 10 commercial buildings and ?8 out of 10 homes in California are not insured for earthquakes.
“Cities won’t be usable for many months, if not years,” said H. Kit Miyamoto, a member of the California Seismic Safety Commission, a government body that advises the state Legislature on earthquake issues.In a severe earthquake, most American buildings are designed to crumple like a car in a head-on collision, dissipating the energy of the earthquake through damage. The goal is to preserve lives, but the building may be useless.
Some cities like San Francisco are considering rules that would require buildings to be more rigid, similar to those in Japan. There is no such thing as earthquake-proof construction, but experts say American buildings could be much more resilient for little additional cost.
A multiyear federal study concluded that fixing buildings after an earthquake costs four times more than building them more strongly in the first place.
Evan Reis, a co-founder of the U.S. Resiliency Council, a nonprofit organization, says the biggest impediment is that buildings change hands frequently in America and the developers who build them do not see the incentive in making them more robust.
“Short-term thinking is absolutely the biggest villain,” Reis said. “People are willing to roll the dice.”