Seismic Isolation and Supplemental Energy Dissipation Introduction Basic Concepts, Modeling, and Analysis Earthquake Response Spectrum Analysis • Structural Dynamic Response Modifications • Modeling of Seismically Isolated Structures • Effect of Energy Dissipation on Structural Dynamic Response 41 Seismic Isolation and Energy Dissipation Devices Elastomeric Isolators • Sliding Isolators • Viscous Fluid Dampers • Viscoelastic Dampers • Other Types of Damping Devices Performance and Testing Requirments Seismic Isolation Devices • Testing of Energy Dissipation Devices. | Zhang R. Seismic Isolation and Supplemental Energy Dissipation. Bridge Engineering Handbook. Ed. Wai-Fah Chen and Lian Duan Boca Raton CRC Press 2000 41 Seismic Isolation and Supplemental Energy Dissipation Rihui Zhang California State Department of Transportation Introduction Basic Concepts Modeling and Analysis Earthquake Response Spectrum Analysis Structural Dynamic Response Modifications Modeling of Seismically Isolated Structures Effect of Energy Dissipation on Structural Dynamic Response Seismic Isolation and Energy Dissipation Devices Elastomeric Isolators Sliding Isolators Viscous Fluid Dampers Viscoelastic Dampers Other Types of Damping Devices Performance and Testing Requirments Seismic Isolation Devices Testing of Energy Dissipation Devices Design Guidelines and Design Examples Seismic Isolation Design Specifications and Examples Guidelines for Energy Dissipation Devices Design Recent Developments and Applications Practical Applications of Seismic Isolation Applications of Energy Dissipation Devices to Bridges Summary Introduction Strong earthquakes impart substantial amounts of energy into structures and may cause the structures to deform excessively or even collapse. In order for structures to survive they must have the capability to dissipate this input energy through either their inherent damping mechanism or inelastic deformation. This issue of energy dissipation becomes even more acute for bridge structures because most bridges especially long-span bridges possess very low inherent damping usually less than 5 of critical. When these structures are subjected to strong earthquake motions excessive deformations can occur by relying on only inherent damping and inelastic deformation. For bridges designed mainly for gravity and service loads excessive deformation leads to severe damage or even collapse. In the instances of major bridge crossings as was the case of the San Francisco-Oakland 2000 by CRC Press LLC .
