WORLD PROPERTY CHANNEL ®

Jay Berger

(OAKLAND, CA) -- Eager to study how improved construction methods in Chile could help the U.S. manage a major earthquake, Earthquake Engineering Research Institute of Oakland, CA is preparing shortly to leave for South America.

"This is especially fertile ground for researchers to find out how effective our own measures are [in] handling these kinds of events," EERI Executive Director Jay Berger tells Engineering News-Record.

The February 27th  Chile earthquake provides another opportunity to study the effectiveness of seismic-code details and damage-mitigation efforts, Berger says.

ENR.com reports "the most powerful earthquake to strike Chile in a generation may have left hundreds dead and the South American nation's infrastructure in tatters, yet the fact the destruction was not far worse is being cited as a testament to Chile's application of improved building codes and decades of efforts to prepare."

Nine died and seven were missing--with some believed trapped alive behind a wall that took the load - when the 70-unit Alto Rio Apartment complex in Concepción rolled off its foundations.

Alfonso Bastias

Investigators likely will study the structure's performance for what worked and what didn't.

"The big numbers tell us that we are doing our homework," said Alfonso Bastias, a civil engineering professor at Pontifical Catholic University of Chile in Santiago.

The magnitude-8.8 quake hit early in the morning on Feb. 27, offshore from the Maule Region. It is the strongest quake to rock Chile since a magnitude-9.5 quake in 1960--the most powerful seismic event ever measured.

According to the Chilean government, on March 2 the death toll from the new quake stood at 723. More than 500,000 homes have been seriously damaged or destroyed, and more than 2 million people have been directly affected.

Transportation and communications systems were brought to a complete standstill, and more than 1.5 million people were without power in the quake's immediate aftermath.

A great deal of the damage reported so far seems to have been to older structures, says Bastias. More modern buildings that collapsed will be examined to see if they were built properly to code.

For decades, Chile has bolstered both its construction standards and emergency response plans to handle major seismic events.

The country's building codes are considered on par with regions in the U.S.--such as California and the Pacific Northwest--that are similarly susceptible to earthquakes, according to ENR.com.

Taller buildings, for example, feature frame construction designs to enhance stability. Buildings taller than eight stories feature a stiff, continuous system of structural walls that help control drift and dampen the worst effects of a temblor.

Despite the upbeat assessments, Chile faces a massive rebuilding job. Insured losses have been pegged at more than $2 billion, with total economic losses expected to exceed $15 billion, according to catastrophe-modeling firm AIR Worldwide.

While the Chile earthquake was more than 500 times more powerful than the one that struck Haiti, there were a number of critical differences between the two disasters, says Paul Caruso, a geophysicist with the U.S. Geological Survey in Golden, Colo.

"In this case it may not be as much of the mechanism as the location of the epicenter and depth of the event itself," he says.

The earthquake in Haiti occurred at a depth of 13 km and struck almost precisely beneath the country's largest populated area, the capitol of Port-au-Prince, while Chile's quake was 35 km deep and centered offshore, more than 100 miles from the nearest major metropolitan area.

But the most important difference between the two disasters was the degree of preparedness, officials say.

Haiti's penultimate major seismic event occurred almost two and a half centuries ago. In Chile, temblors are common, and many still remember the devastation wrought by the quake of 1960, which struck the same area as Saturday's quake.

That magnitude-9.5 quake claimed 1,655 lives and left more than two million people homeless, according to ENR.com.

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