Designing a Quake-Resistant Building Starts at the Soil скачать в хорошем качестве

Designing a Quake-Resistant Building Starts at the Soil

I'm Alex Villarreal with the VOA Special English Technology Report, from http://voaspecialenglish.com |   / voalearningenglish   Builders in developing countries are often not required to build strong buildings. So, when a disaster strikes, the damage is often widespread. Yet Japan is one of the most developed countries in the world. Still, the March eleventh earthquake and tsunami waves destroyed more than fourteen thousand buildings. Brady Cox is an assistant professor of civil engineering at the University of Arkansas. He is also an earthquake expert with an organization called Geotechnical Extreme Events Reconnaissance, or GEER. The group studies major disasters. Professor Cox says Japan has one of the best building-code systems in the world. However, he says, this earthquake was huge, one of the top five earthquakes in recorded history. So anytime there is an earthquake that large, there is going to be damage. The quake measured magnitude nine. He says one thing many people don't understand is that building codes are meant to prevent loss of life in earthquakes. That doesn't mean that the buildings won't have major damage. Mr. Cox says Japan has invested a lot in seismic research and design since a magnitude seven point five earthquake in Niigata in nineteen sixty-four. That same year a nine point two quake shook the American state of Alaska. He says those two earthquakes opened up a lot of new research on something called soil liquefaction. Soil liquefaction is the process by which the strength or stiffness of soil is weakened by an event like the shaking of an earthquake. The soil begins to move like liquid. Professor Cox says the first step to designing an earthquake-resistant building is to study the soil. Then the structural engineers take that information and decide the details of the construction such as, is this going to be a steel structure? Is it going to be reinforced concrete? How will the framing of the building be designed?A team from Geotechnical Extreme Events Reconnaissance is going to Japan to examine the destruction. Mr. Cox says they will also be working on rebuilding efforts. They want to make sure that schools, hospitals, police and fire stations and government buildings are rebuilt well. Mr. Cox and other members of GEER went to Haiti after the powerful earthquake last year, and continue to work with Haitian officials.For VOA Special English, I'm Alex Villarreal. (Adapted from a radio program broadcast 28Mar2011)