Contact: Bob Ratliff
Memphis, Los Angeles and other cities near seismic fault lines may be safer in the future as a result of a complex $1.6 million study now being led by Mississippi State University.
Scientists on the Starkville campus are working with counterparts at Carnegie Mellon University in Pittsburgh, Pa., and the University of California at Berkeley, to investigate the impact of large-magnitude earthquakes on urban areas. The Los Angeles basin, which sits on the edge of the Golden State's famous San Andreas Fault, is the study's primary focus.
Principal investigator Michael Stokes of MSU's Engineering Research Center said the completed computer models will "simulate the response of the earth due to slippage of a fault in the earth's crust." The research professor and his colleagues are in the second year of their four-year, National Science Foundation-supported effort.
"We are working to estimate the amount and distribution of damage throughout an urban region," Stokes said. "To accomplish this, we're using realistic computer-generated models of buildings and bridges, soil structure and other characteristics of urban areas."
City planners, state and federal emergency management agencies, insurance companies and others dealing with urban risk analysis and reduction should be among the first to benefit from the new software.
"Knowing that some locations have higher ground motion than others during an earthquake will result in the design of safer structures and overall reduction of risks to occupants of buildings," Stokes said. "The data from this project will allow for that type of planning in the areas of the nation most likely to have seismic activity."
Those areas include Southern California, the inter-mountain seismic belt around Salt Lake City; the New Madrid Fault system, including Eastern Missouri and West Tennessee; and an area along the East Coast centered in South Carolina.
Stokes said research team member Jacobo Bielak, a Carnegie-Mellon civil engineer, is developing the methodology and high-performance computer software that simulates ground motion.
"During an earthquake, there's a great deal of interaction between buildings and the earth beneath them, including compaction of the soil as the buildings move," Stokes explained. "Our job is to tie together all of these things, including the ground motion simulation, the response of the man-made infrastructure and the visualization.
By combining these with the movement of buildings, reaction of the soil and other factors, the MSU-led team will have the most physically correct computer model ever developed.
UC-Berkeley civil engineer Gregory Fenves is modeling buildings, bridges and other man-made structures to study how they respond to the movement of the ground beneath them.
"We want to understand, for instance, why an earthquake heavily damages a type of building in one area and the same type receives less damage in another area," Fenves said. "If we understand why that happens, we can use that knowledge to develop better design procedures, building codes and ways of zoning."
When all the data is collected, MSU computer scientists Joerg Meyer and Tomasz Haupt will bring the software into its final form.
Meyer said the completed product will be Internet-accessible and immediately available to display in a virtual environment such as "the COVE," a room-sized enclosure at MSU's Engineering Research Center that features three rear-projected sidewalls and a floor that is top-down projected.
"Using the COVE or a similar virtual environment, a user can become immersed in the scene by walking between skyscrapers while the buildings are shaking," Meyer said. "The addition of audio also will enhance the feeling of an actual earthquake."