Published August 15, 2013
Researchers from The Johns Hopkins University will conduct tests tomorrow to see how a Southern California earthquake could impact a two-story office building.
But the tests are not being held at Johns Hopkins. Or in Southern California. They’re being held in UB’s Structural Engineering and Earthquake Simulation Laboratory, where two shake tables will mimic the strongest seismic forces recorded during the catastrophic Northridge earthquake of 1994.
Johns Hopkins’ researchers chose to work at UB because the university has the only earthquake simulation lab in the U.S. that is capable of replicating an earthquake in three directions beneath a building measuring 50 feet long, 20 feet wide and 20 feet tall. Several local contractors, including Mader Construction Co. of Elma and ALP Steel of Buffalo, have worked on the project.
UB researchers and other collaborators have been conducting research on the shake tables since the earthquake simulation lab was opened in 2004. The dual-movable, six-degree-of-freedom shake tables, made by MTS Systems Corp., can easily be repositioned within the lab for real-time seismic testing of structures up to 120 feet long and 30 feet high.
Most recently, UB earthquake engineers simulated the Virginia quake that rattled the East Coast in 2011 to determine how vulnerable panel walls within New York City row houses are to temblors. During that test, held last February, two 14-foot-tall walls, built with materials such as 100-year-old brick, were put on a shake table that mimicked the Virginia quake.
In tomorrow’s test, Johns Hopkins researchers will be trying to find out how well a two-story building made of cold-formed steel, which is recycled steel, can stand up to forces comparable to those at the epicenter of the 1994 Northridge earthquake in Los Angeles that claimed dozens of lives and caused billions of dollars in damage.
Trials will include four low-level tests, each lasting 90 seconds, and one “big test” that replicates the Northridge quake. This test will last about 30 seconds.
Lead researcher Benjamin Schafer, Swirnow Family Scholar, professor and chair of the Department of Civil Engineering in the Whiting School of Engineering at Johns Hopkins, says this will be the first such test of a full building of cold-formed steel framing.
The results are expected to lead to improved nationwide building codes that may make future cold-formed steel buildings less expensive to construct than those made of such materials as timber, concrete or hot-rolled steel, as well as help reduce the likelihood of costly and life-threatening building collapses in earthquake-prone regions.
It also could lead to broader use of building components made of the environmentally friendly cold-formed steel, which is made of 100 percent recycled steel.