RESEARCH: STRUCTURAL DYNAMICS Devices are installed in buildings to dissipate energy during a seismic event New devices dissipate energy using different types of damping than traditional viscous damping The more energy is dissipated, the less energy in the system to damage the structure and its occupants RISE Student: Anna Whittaker, Civil and Environmental Engineering Major, Class of 2015 Research Mentor: Dr. Brian Phillips, UMD Assistant Professor, Civil and Environmental Engineering Department Destruction due to the 2010 Haiti Earthquake Objective: To create and model new devices to mitigate damage caused by earthquakes and impulses

RESEARCH: STRUCTURAL DYNAMICS Our device concepts are modelled virtually in Simulink using structural dynamics Device performance is compared to traditional devices like Tuned Mass Dampers (TMD’s)

RESEARCH: STRUCTURAL DYNAMICS Existing Devices Tuned Mass Dampers work well and cannot add energy to a system, so they cannot cause additional damage However, they must be tuned to the natural frequencies of the building, and can therefore become useless if they are damaged during a seismic event. They are also very large (see image). Devices that dissipate energy through impact work well and do not need to be tuned, but they could potentially be dangerous and cause more damage to the structure Our Devices The devices we are working on dissipate energy nonlinearly and operate about as well as TMD’s Their mitigation capabilities are “tuned” using material stiffness and device geometry, so there is a much smaller chance that damage during a seismic event will hinder their performance They are active, meaning they can be adjusted during a seismic event according to performance feedback The TMD in Taipei 101, Taiwan occupies 6 floors