212 Ketter Hall, North Campus, Buffalo, NY Fax: Tel: x 2400 Structural Control through Base Isolation Andrei M Reinhorn Professor of Structural Engineering
Modern Methods in Earthquake and Vibration Mitigation
Elastomeric / Natural Rubber Isolators
Spectral Response Target Period 2-3sec
Spectral Response
Site Effects on Spectral Response
Steel-Laminated Elastomeric Bearings Curtesy Scougal Rubber, Seattle, WA
Deformed Seismic High Damping Rubber Bearing
Lead Rubber Bearing
Whitestone Bridge - Rubber Bearings
Friction Pendulum System
Liquid Natural Gas (LNG)Tanks Friction Pendulum System 212 Isolators -20 o C - 30 o C 1000 tons capacity 5% friction +/-30 cm lateral movement period of 2.75 sec
Hayward City Hall, CA 53 FPS 15 Taylor Fluid Dampers Period 3.0 sec 3.5% Friction +/-28 cm movement 900 tons capacity
22 FPS 5 sec period +/ m movement 2200 tons capacity R=6.2m
San Francisco Airport International Terminal 267 FPS 3 sec period +/- 60 cm movement 3000 tons capacity
Court of Appeals San Francisco CA Building Retrofitted with 256 Isolators of type Friction Pendulum System
Historic Monument Suffered Damage in 1989 Loma Prieta Earthquake
Installation of FPS Construction of Side Beams Cutting hole for jacks and column removal
Installation of damper Damper in place and grouted to receive load Cutting the wall along the building
Court of Appeals- Retrofit of Interior Walls Protected During Construction Interior After Retrofit
Ball-in-Cone Isolator - Tekton Dev., Arizona
Wire Rope Isolators
Elastomeric Bearing Models 2R t
Elastomeric Bearings Properties Horizontal Stiffness Vertical Stiffness t r = net rubber thickness A t Circular Bearing Square Pad Holed Circular Pad for strip for circular for square
Elastomeric Bearings Properties Moment Capacity of Circular Pad Effective Stiffness for Square Pad Effective Stiffness for Holed Pad Effective shear strain Effective Stiffness for Circular Pad (EI) eff = E c R 4 /12
Modified Stiffness- Modified Stiffness for Large S Modified Stiffness for Very Large S For Circular Pad - Small S For Circular Pad Large S K - bulk modulus of material
Lead Rubber Bearings
Friction Pendulum System D WW Force Resistance Horizontal Stiffness Effective Stiffness Basic Period
Friction Pendulum System D WW
Design Procedure
Design Example
D
Design Analysis 3D-Basis-Tabs series of computer programs available Report * and Program SAP2000 available from Computers and Structures, Berkeley, CA IDARC-BRIDGE from University at Buffalo /MCEER Report # * and Program (program requires SUN / UNIX computer) * Reports can be obtained from MCEER / University at Buffalo Publications department
212 Ketter Hall, North Campus, Buffalo, NY Fax: Tel: x 2400 THANKS FOR YOUR ATTENTION