Yi-Lung Mo
University of Houston, USA
Title: Periodic materials for dynamic design of energy infrastructures
Biography
Biography: Yi-Lung Mo
Abstract
Conventional dynamic isolation systems currently under development employ high-damping rubber bearings, lead rubber bearings, or friction pendulum bearings. These systems are effective in reducing the damaging eff ects of the horizontal components of a dynamic excitation, but they are not well suited for protection against the vertical components of dynamic loads. Current dynamic isolation systems also cause large relative horizontal displacement between the foundation and the supported structure, which occurs during a dynamic excitation event, further complicating the design. A gap is usually provided between the isolated structure and the surrounding non-isolated structures to avoid hammering. A design that eliminates the need for such design restrictions would be very attractive. The proposed technology will attempt to overcome the disadvantages existing in current dynamic isolation systems by developing innovative periodic material-based dynamic isolators. These dynamic isolators, in effect, use the foundation of the infrastructure as the base isolation system. The foundation is made
of a new material, called periodic material, which can block, or reflect, the damaging dynamic motion being transmitted to the infrastructure. Guided by solid state physics, the dynamic isolators can be made by the periodic material to exhibit special characteristics that are useful in resisting the loads imposed on structures from dynamic excitations. Possessing distinct frequency band gaps, this periodic material will block, or reflect, the incoming dynamic motion with the frequencies falling between these gaps. The frequency band gaps can be controlled by their design and manufacture, exactly what is needed for dynamic isolators. One can properly design the frequency band gaps to match the fundamental frequency of the infrastructure so that its dynamic response will not be amplified; alternatively, one can design the frequency band gaps to match the strong energy frequency components of the design dynamic load.