Engineers in Chile to observe, measure, improve
Dan Dolan, civil engineering professor, and Gonzalo Montalva, a graduate student, were part of several research teams that went to Chile to assess the damage from the 8.8 magnitude earthquake that hit the country Feb. 27. The earthquake had the fifth largest magnitude ever recorded and is the largest for which engineers have structural measurements and data.
“Advancing earthquake-resistant design requires a better understanding of what happened during the quake,” said David Frost, a professor of civil engineering at Georgia Tech and co-chair of Geo-engineering Extreme Events Reconnaissance (GEER), in a press release.
Soils and structures
WSU already is connected to Chile through a relationship with the University of Concepción (UDC). The universities collaborate on programs and frequently exchange faculty: Dolan has traveled to Chile and Montalva, originally from Chile, is an associate professor at UDC. He will be back in Concepción this fall to continue post-earthquake learning and reconstruction work.
He was part of the first team, a part of GEER and sponsored by the National Science Foundation, which left March 4, within a week of the quake, for an eight day trip. The goals of the group were to study natural as well as man-made structures’ responses to the earthquake. The team studied soil impacts as well as bridges, highways and building foundations.
The team focused on soils and the mutual impact between soils and structures during an earthquake. They studied liquefaction, subsidence and amplification of waves through the soil. Known as site effects, this variation in amplification means that different areas can experience the same shaking with different impacts.
Typically, researchers think soil failure causes structures to fail. However, Montalva said the team saw evidence that the buildings impact the soil, softening it, which then impacts the structures.
“We as an organization go to all these types of events, hurricanes as well, to learn how our structures perform and how we can learn from them,” Montalva said.
Diverse teams, focuses
Chile is a modern country with a seismic code similar to the western United States. Montalva’s team of about 20 studied the approximately three percent of buildings in Chile that failed. Their goal was to learn what revisions could be made to the geotechnical part of building codes. Bridge failures also were documented and will continue to be studied.
“We see a lot of reinforced concrete structures that behaved really well and some that didn’t,” he said.
Dolan went with an American Society of Civil Engineers (ASCE) team to Chile on a weeklong trip, beginning April 5. Dolan’s team was one of three sent by ASCE in April to gather data on infrastructure response to natural disasters. These teams will be applying their findings to United States situations and Chilean rebuilding efforts.
All the teams are diverse, sending researchers from a range of American universities. In addition, teams from China, France and Japan were also in Chile studying the impacts of the earthquake.