It helped to be Chinese. It helped even more to have a friend who is an earthquake damage inspector for the Chinese government.
As the two men traveled through central China for 10 days last month, Zhenming Wang, who heads the Kentucky Geological Survey’s Geological Hazards Section at the University of Kentucky, tried to blend in and let his friend do the talking.
As a result, Wang got a rare insider’s look at the devastation wrought by the magnitude 8.0 earthquake that struck China on May 12, killing nearly 70,000 people and displacing tens of thousands more.
Wang also was able to gather valuable data to help Western Kentucky prepare for an inevitable repeat of similar quakes that hit along the New Madrid Fault near the Mississippi River in 1811 and 1812. The good news: It might not be as bad as we’ve always thought.
Photos Wang took during his trip vividly show the destruction in China: A collapsed bridge span. A new luxury hotel so cracked it must now be torn down. Schools reduced to rubble. A family eating lunch in the ruins of their home, which no longer has a roof or walls. A huge boulder that rolled off a mountain, crushing a car on the road below. Along the fault line, rows of corn are rearranged and a waterfall has appeared in a river.
Still, the ground-shaking that occurred for perhaps two minutes during the quake wasn’t as severe as Wang expected.
Some buildings were destroyed, but others next to them were hardly damaged. That was especially true near the fault line, where structures on one side were often more damaged than on the other.
In some cases, damaged or destroyed buildings were not properly designed to withstand as much ground-shaking as they received. In many more cases, though, the damage was the result of shoddy construction, he said.
That was often true in schools, which is why so many of the dead were children crushed in their classrooms. Wang has one photo of a bulletin board in a destroyed school’s main hall. It is filled with students’ portraits. “I don’t know how many of them survived,” he said. “It was very, very sad.”
Wang said he talked with a woman whose young son had died when his school collapsed, and now she faced having to demolish her recently built but damaged home. The boy’s friend lived nearby; he escaped because he was able to run quickly out of the school when the quake began.
“Everywhere I went, if they put just a little design and construction attention to it, it was fine,” said Wang, who is from southeast China, far from the earthquake zone. “If people had just spent a little more money. Economically, they could have afforded to do it. This was both a natural and a man-made disaster.”
While China did too little to prepare for this earthquake, Western Kentucky might have done too much. Wang said his research estimates that ground-shaking around Paducah during a worst-case New Madrid quake would likely be only half as strong as previous estimates.
“Previously, in Paducah, builders had to do more than in San Francisco and L.A., and that just didn’t make sense,” he said. “I can now see several federal agencies revising certain things.”
Wang said there are differences in geology between China and Western Kentucky and Tennessee, and many more differences in topography. For example, many people in China died in huge landslides. “We certainly wouldn’t have this landslide issue, because our land is flat,” he said.
But there is danger from so-called “liquefaction,” where the ground basically turns to soup and buildings sink. That’s of special concern in Memphis.
Based on his research, and other new science, Wang thinks some building codes for bridges and public buildings in Western Kentucky could be further eased, which would save money and help the area’s battered economy. Residential building codes already have been revised in recent years.
“Clearly, the estimate for ground motion in Paducah is too high,” Wang said. “The methodology they used is flawed. It was based on what we knew in the 1960s and 1970s. We know more now than then.”
Wang said he hopes his research will be useful in finding the right balance in earthquake construction standards – protecting public safety without unnecessarily driving up costs.
“My job is to look at the science, and let the policy-makers make those decisions,” he said.
