Colorado State University Researchers Set to Collapse Three-story Building with Virtual First Floor to Test Earthquake Retrofit Systems

A team of researchers led by Colorado State University will complete the second phase of testing earthquake retrofitting for buildings with open, or “soft,” first stories on Monday, Oct. 28, in the SEES lab at the University at Buffalo in New York.

The five-university collaborative research project involving CSU, Clemson University, Western Michigan University, Rensselaer Polytechnic Institute, and Cal-Poly Pomona, has been running simulations on various systems to mitigate damage from seismic events on multi-story buildings with the first floor devoted to open spaces, such as for parking or retail. Monday’s test will be a full-scale collapse test, in which the top two stories of a three-story structure will be pushed to the collapse limit.

The tests are part of the NEES-Soft project, sponsored by the National Science Foundation. The shake tables on the university’s North (Amherst) campus are part of the NSF’s Network for Earthquake Engineering Simulation.

In the NEES-Soft at Buffalo testing, the bottom or “soft” story is simulated by a computer model. This allows researchers to easily vary the amount of modification to the structure to determine the optimum amount of retrofitting of the first floor needed to protect the upper floors from collapse.

“Earthquakes are particularly damaging to buildings with open spaces at street level because they collapse – that first-floor parking makes the building structurally weak and soft,” said Principal Investigator John van de Lindt, the George T. Abell Professor in Infrastructure in the CSU College of Engineering. “The computer model lets us test innovative approaches to reinforcing structures without the time and expense of building actual structures.”

In August, the research team, led by John van de Lindt, completed a series of tests on a full-scale four-story building on the outdoor shake table at the University of California at San Diego, also part of NEES.

The design of the soft-story wood-frame building used in the test is based on residential structures built prior to the 1920s throughout California, and still in use in earthquake prone areas such as the San Francisco Bay Area.

To watch the test live, beginning at 10 a.m. Eastern time on Monday, go to