Researchers at the University of Arizona are examining steel collectors used in the building industry to help create earthquake-proof structures.
Major earthquakes in central Mexico and the Iran-Iraq border last year caused large scale devastation and death, killing about 900 people, and destroying hundreds of buildings that also left many homeless.
Working in partnership with Lehigh University and the University of California, San Diego, the Arizona University-led research team is now studying steel collectors, which are reinforcements used in concrete floor slabs, and responsible for horizontally transferring seismic forces.
Up until now, any research into seismic building safety has focused on walls and braces, which form a downward load path to transfer seismic forces through a building's foundation and into the ground using a network of structural fuses.
However, the frames and walls aren't the only parts of a building affected by seismic forces; forces cannot be transferred vertically from walls and braces to the earth unless the steel collectors first transfer those forces horizontally from the floor to the fuses in the walls and braces.
Robert Fleischman, UA professor of civil engineering and engineering mechanics, is the principal investigator (PI) for the project, “Advancing Knowledge on the Performance of Seismic Collectors in Steel Building Structures”.
While Lehigh has the largest structures lab in the United States, the UCSD is home to the nation’s largest outdoor shake table, which features a movable platform driven by pressurised oil, and simulates earthquake conditions on structures.
Since conducting a test on a shake platform is very expensive, the researchers run computer simulations to develop the best possible model for the actual shake table test without the cost of testing physical structures.