Building designs that rock during an earthquake and return to a plumb, upright position could withstand earthquake conditions better than other structural designs currently used in earthquake-friendly areas such as California, according to a researcher from Case Western Reserve University. By using a computer model that compares the rocking steel-braced frame design with conventional buildings, project head Michael Pollinowas able to determine that the new technology would outperform current standards in low- to mid-rise buildings.
In addition to showing that the new design may hold up to earthquake conditions better, the model also suggests the best sizes for two components of the building design: viscous damping devices, which work like shock absorbers on a car, and steel-yielding devices, which limit the amount of force that can be transferred throughout the structure.
Unlike traditional designs, in a rocking steel-braced frame system the columns are not anchored to the building foundation, but attached to the foundation by the dampers and steel-yielding devices. This construction allows the building’s frame to lift off the foundation and tilt when earthquakes strike, with the devices dissipating seismic energy to reduce the risk of damage.