Earthquake Protector

Heavy damping mechanism sometimes incorporated in vibration control technologies and, particularly, in base isolation devices may be considered a valuable source of suppressing vibrations thus enhancing a building's seismic performance. However, for the very pliant systems such as base isolated structures, with a relatively low bearing stiffness but with an high damping, the so-called "damping force" may turn out the main pushing force at a strong earthquake [http://www.ecs.csun.edu/~shustov/Topic4.htm] . This finding created a theoretical ground in earthquake engineering for a damping-disengaged base isolation technology called Earthquake Protector [https://central.nees.org/data/get/NEES-2006-0283/Public/REPORT.pdf] .

A video clip of concurrent shake-table experiments with two identical and kinematically equivalent to their 12-story prototype building models is presented at [http://www.youtube.com/watch?v=kzVvd4Dk6sw] . The right model is resting on Earthquake Protectors, while the left one, caught at the time of its crash, is fixed to the shake-table platen [https://central.nees.org/?action=DisplayProjectMain&projid=283] . At this experiment, the fundamental natural period of the building model superstructure is about 1.2s, the isolated period of the Earthquake Protector is 5.0s, the range of the earthquake simulation periods is 0.02 - 2.00s, and the maximum ground acceleration is about 1.0g [http://www.ecs.csun.edu/~shustov/EP-2006.htm] .

Analytical software called Earthquake Performance Evaluation Tool (EPET) enables concurrent virtual experiments on the same building models "with" and "without" Earthquake Protectors.