Evacuees gather at a shelter in the Japa
Kazuhiro Nogi  /  AFP / Getty Images
The devastating loss of life in last week's disaster suggests that even Japan's sophisticated earthquake and tsunami warning systems didn't have enough tsunami shelters to give people safe haven — and those that exist don't follow any one standard. This photo shows evacuees at a shelter in Minami-sanriku, Miyagi Prefecture, in February 2010, when  Japan evacuated more than 320,000 people as a huge Chilean quake sent a tsunami up to 4 feet high barrelling into its coast.
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updated 3/15/2011 7:06:35 PM ET 2011-03-15T23:06:35

Japan's buildings may have mostly survived the massive 9.0-magnitude earthquake that struck last Friday, but thousands of people died because of the deadly tsunami that followed and swept away entire coastal towns. Now the Japanese have the chance to rebuild even stronger defenses to safeguard the lives of its citizens, experts say.

The country has one of the most sophisticated earthquake and tsunami warning systems in the world, as well as seawalls, fortlike floodgates and some tsunami shelters. Yet the devastating loss of life suggests that not enough tsunami shelters existed to give people safe haven above the waves — and those that exist don't follow any one standard.

"There are so many kinds of tsunami shelters in Japan," said Harry Yeh, a civil engineer at Oregon State University in Corvallis. "There is no standard design at all for evacuation buildings. That's the reason we cannot follow (for U.S. building shelters)."

More disaster was prevented because of Japan's stringent building code that requires new buildings to hold up against collapse during maximum-event earthquakes. The country also has thousands of seismic-protective systems to protect important buildings such as hospitals, along with some apartment and office buildings.

But many of the systems undergo less-rigorous hazard analysis and testing compared to the systems in quake-prone California, according to Michael Constantinou, a civil engineer at the University of Buffalo in Buffalo, N.Y. Japanese systems are also designed for lower-level earthquakes than their California counterparts, in part because of the choice of technology.

"Bridges in Japan are designed for higher earthquake hazards than the buildings next to them," Constantinou told InnovationNewsDaily. "This, in my opinion, is problematic."

Deadly lessons from the ocean
The main loss of life in Japan came from the tsunami spawned by the earthquake. Such tragedy occurred despite Japan having the best tsunami defenses in the world and a "very impressive" warning system, said Yeh.

Yeh was watching a Japanese TV channel when he saw a tsunami warning pop up just five minutes after the earthquake. The first waves arrived 30 minutes after the earthquake, which left many coastal villagers without time to reach safety – if any higher ground or shelters existed nearby. Cities such as Tokyo fared better with their more extensive seawalls and floodgates.

Some Japanese tsunami shelters resemble towers, while others merely involve a platform sitting atop concrete pillars. But even that patchwork collection of shelters beats the total lack of tsunami shelters in the U.S.

Tsunami experts had previously scoffed at the idea of even building tsunami shelters — at least until the 2004 Indian Ocean tsunami killed 230,000 people. That led to the realization that even educating people about fleeing the coast might not save their lives.

"Even if we educate people to go to higher ground, there may be no higher ground," Yeh said in a phone interview with InnovationNewsDaily.

The first proposed U.S. tsunami shelter is designated to double as the town hall for Cannon Beach, Ore., but only if the town can find the funding. Yeh and his colleagues have been working on simulation models of the tsunami forces and evacuation procedures for such a shelter.

Steady on the shaking
Japan's bitter experience with tsunamis has naturally gone hand-in-hand with its history of earthquakes. The country went on a frenzy of quakeproofing following the 1995 Kobe earthquake that killed more than 6,400 people, and now has the largest array of such protective systems in the world.

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"It's not something you can do overnight, but over the last 15 years practically every important building in Japan has been fitted with these systems," Constantinou said. "Even in some apartment buildings, they proceeded with application of this technology."

The thousands of protective systems include so-called seismic isolators that protect a building similar to how shock absorbers cushion passengers in a car. In Japan, many buildings sit atop bearings which consist of stacked and bonded layers of rubber and steel. The rubber allows for horizontal stretching during a quake.

Still, such rubber-based systems can stretch only so far during the most massive earthquakes. California has favored so-called friction pendulum isolators that use a lubricated slider trapped between steel plates to permit even greater stresses from quakes, but Japan has been slow to install such systems, Constantinou said.

Both Japan and California also use steel braces attached throughout a structure to dissipate some of the earthquake energy, as well as more advanced "viscous dampers" that resemble steel pistons.

California requires intensive surveys to figure out the site-specific seismic hazard for each building, whereas Japan uses a standard suite of recorded earthquake motions as a general rule for installing such systems — something that is "unacceptable" in California.

"Applications in Japan consider a lower-level earthquake for the design, (because) the displacement capacity of the isolation systems is much less," Constantinou explained. "Also, review and plan-checking appear not as rigorous as in California."

Constantinou seemed certain that Japan would apply even more rigorous standards in the wake of its latest disaster. He also acknowledged the huge challenge Japan faced in the "one-two combination" of the earthquake and tsunami.

"This is really a catastrophe," Constantinou said. "But I think they did really well."

This article was provided by InnovationNewsDaily, a sister site of TechNewsDaily.

© 2012 TechNewsDaily

Explainer: The 10 deadliest earthquakes in recorded history

  • A look at the worst earthquakes in recorded history, in loss of human life. (The March 11, 2011, earthquake and tsumani that affected eastern Japan is not included because the fatalities caused, about 15,000, are fewer than those resulting from the temblors listed below.) Sources: United States Geological Survey, Encyclopedia Britannica

  • 1: Shensi, China, Jan. 23, 1556

    Magnitude about 8, about 830,000 deaths.

    This earthquake occurred in the Shaanxi province (formerly Shensi), China, about 50 miles east-northeast of Xi'an, the capital of Shaanxi. More than 830,000 people are estimated to have been killed. Damage extended as far away as about 270 miles northeast of the epicenter, with reports as far as Liuyang in Hunan, more than 500 miles away. Geological effects reported with this earthquake included ground fissures, uplift, subsidence, liquefaction and landslides. Most towns in the damage area reported city walls collapsed, most to all houses collapsed and many of the towns reported ground fissures with water gushing out.

  • 2: Tangshan, China, July 27, 1976

    Chinese Earthquake
    Keystone  /  Getty Images
    1976: Workers start rebuilding work following earthquake damage in the Chinese city of Tangshan, 100 miles east of Pekin, with a wrecked train carriage behind them. (Photo by Keystone/Getty Images)
    Magnitude 7.5. Official casualty figure is 255,000 deaths. Estimated death toll as high as 655,000.

    Damage extended as far as Beijing. This is probably the greatest death toll from an earthquake in the last four centuries, and the second greatest in recorded history.

  • 3: Aleppo, Syria, Aug. 9, 1138

    Magnitude not known, about 230,000 deaths.

    Contemporary accounts said the walls of Syria’s second-largest city crumbled and rocks cascaded into the streets. Aleppo’s citadel collapsed, killing hundreds of residents. Although Aleppo was the largest community affected by the earthquake, it likely did not suffer the worst of the damage. European Crusaders had constructed a citadel at nearby Harim, which was leveled by the quake. A Muslim fort at Al-Atarib was destroyed as well, and several smaller towns and manned forts were reduced to rubble. The quake was said to have been felt as far away as Damascus, about 220 miles to the south. The Aleppo earthquake was the first of several occurring between 1138 and 1139 that devastated areas in northern Syria and western Turkey.

  • 4: Sumatra, Indonesia, Dec. 26, 2004

    Aerial images show the extent of the devastation in Meulaboh
    Getty Images  /  Getty Images
    MEULABOH, INDONESIA - DECEMBER 29: In this handout photo taken from a print via the Indonesian Air Force, the scene of devastation in Meulaboh, the town closest to the Sunday's earthquake epicentre, is pictured from the air on December 29, 2004, Meulaboh, Aceh Province, Sumatra, Indonesia. The western coastal town in Aceh Province, only 60 kilometres north-east of the epicentre, has been the hardest hit by sunday's underwater earthquake in the Indian Ocean. Officials expected to find at least 10,000 killed which would amount to a quarter of Meulaboh's population. Three-quarters of Sumatra's western coast was destroyed and some towns were totally wiped out after the tsunamis that followed the earthquake. (Photo by Indonesian Air Force via Getty Images)

    Magnitude 9.1, 227,898 deaths.

    This was the third largest earthquake in the world since 1900 and the largest since the 1964 Prince William Sound, Alaska temblor. In total, 227,898 people were killed or were missing and presumed dead and about 1.7 million people were displaced by the earthquake and subsequent tsunami in 14 countries in South Asia and East Africa. (In January 2005, the death toll was 286,000. In April 2005, Indonesia reduced its estimate for the number missing by over 50,000.)

  • 5: Haiti, Jan 12, 2010

    Haitians walk through collapsed building
    Jean-philippe Ksiazek  /  AFP/Getty Images
    Haitians walk through collapsed buildings near the iron market in Port-au-Prince on January 31, 2010. Quake-hit Haiti will need at least a decade of painstaking reconstruction, aid chiefs and donor nations warned, as homeless, scarred survivors struggled today to rebuild their lives. AFP PHOTO / JEAN-PHILIPPE KSIAZEK (Photo credit should read JEAN-PHILIPPE KSIAZEK/AFP/Getty Images)

    Magnitude 7.0. According to official estimates, 222,570 people killed.

    According to official estimates, 300,000 were also injured, 1.3 million displaced, 97,294 houses destroyed and 188,383 damaged in the Port-au-Prince area and in much of southern Haiti. This includes at least 4 people killed by a local tsunami in the Petit Paradis area near Leogane. Tsunami waves were also reported at Jacmel, Les Cayes, Petit Goave, Leogane, Luly and Anse a Galets.

  • 6: Damghan, Iran, Dec. 22, 856

    Magnitude not known, about 200,000 deaths.

    This earthquake struck a 200-mile stretch of northeast Iran, with the epicenter directly below the city of Demghan, which was at that point the capital city. Most of the city was destroyed as well as the neighboring areas. Approximately 200,000 people were killed.

  • 7: Haiyuan, Ningxia , China, Dec. 16, 1920

    7.8 magnitude, about 200,000 deaths.

    This earthquake brought total destruction to the Lijunbu-Haiyuan-Ganyanchi area. Over 73,000 people were killed in Haiyuan County. A landslide buried the village of Sujiahe in Xiji County. More than 30,000 people were killed in Guyuan County. Nearly all the houses collapsed in the cities of Longde and Huining. About 125 miles of surface faulting was seen from Lijunbu through Ganyanchi to Jingtai. There were large numbers of landslides and ground cracks throughout the epicentral area. Some rivers were dammed, others changed course.

  • 8: Ardabil, Iran, March. 23, 893

    Magnitude not known, about 150,000 deaths

    The memories of the massive Damghan earthquake (see above) had barely faded when only 37 years later, Iran was again hit by a huge earthquake. This time it cost 150,000 lives and destroyed the largest city in the northwestern section of the country. The area was again hit by a fatal earthquake in 1997.

  • 9: Kanto, Japan, Sept. 1, 1923

    Kanto Damage
    Hulton Archive  /  Getty Images
    1923: High-angle view of earthquake and fire damage on Hongokucho Street and the Kanda District, taken from the Yamaguchi Bank building after the Kanto earthquake, Tokyo, Japan. (Photo by Hulton Archive/Getty Images)
    7.9 magnitude, 142,800 deaths.

    This earthquake brought extreme destruction in the Tokyo-Yokohama area, both from the temblor and subsequent firestorms, which burned about 381,000 of the more than 694,000 houses that were partially or completely destroyed. Although often known as the Great Tokyo Earthquake (or the Great Tokyo Fire), the damage was most severe in Yokohama. Nearly 6 feet of permanent uplift was observed on the north shore of Sagami Bay and horizontal displacements of as much as 15 feet were measured on the Boso Peninsula.

  • 10: Ashgabat, Turkmenistan, Oct. 5, 1948

    7.3 magnitude, 110,000 deaths.

    This quake brought extreme damage in Ashgabat (Ashkhabad) and nearby villages, where almost all the brick buildings collapsed, concrete structures were heavily damaged and freight trains were derailed. Damage and casualties also occurred in the Darreh Gaz area in neighboring Iran. Surface rupture was observed both northwest and southeast of Ashgabat. Many sources list the casualty total at 10,000, but a news release from the newly independent government on Dec. 9, 1988, advised that the correct death toll was 110,000. (Turkmenistan had been part of the Soviet Union, which tended to downplay the death tolls from man-made and natural disasters.)

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