Investigation of a Seismic Base Isolation System Based on Pendular Action

Foutch, D.A.; Gambill, J.B.; Garza-Tamez, F.

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https://hdl.handle.net/2142/14195 Copy

Description

Title

Investigation of a Seismic Base Isolation System Based on Pendular Action

Author(s)

• Foutch, D.A.
• Gambill, J.B.
• Garza-Tamez, F.

Issue Date

1993-08

Keyword(s)

• GT-BIS
• Seismic isolation
• Energy dissipation system
• earthquake motions

Abstract

Experimental and analytical studies of a new seismic isolation and energy dissipation system for buildings were conducted. The system (GT-BIS) was developed by Federico Garza-Tamez of Monterrey, Mexico . The system is composed of four elements: (1) base isolation devices, (2) damping devices, (3) an adjustable clamp which can be used to adjust the effective length of the tension members, and (4) a single pin wind restraint disengaging device. The main components are the isolation devices. The base columns of the building are supported by cables, or rods, or other tension members which are attached to a small frame that encircles each column and rests on the foundation. With proper use of the clamping device the building response to an earthquake is like that of a single-degree-of-freedom pendulum. The clamps may be adjusted to achieve the desired period of vibration. The GT-BIS also employs a novel hydraulic damping system that very effectively dissipates seismic energy. The damping system is designed in such a way that it permits translation but inhibits torsional motion. The wind restraint device utilizes a spring loaded pin which does not allow relative displacement between the building and the foundation under wind loading but disengages when an earthquake occurs. Free vibration, sinusoidal and earthquake simulation tests of a l/8-scale model of a nine story building were conducted on the earthquake simulator at the US Army Construction Engineering Research Laboratory located in Champaign, Illinois. As a results of these tests the following conclusions were made: 1. The GT -BIS isolation system is very effective at reducing the acceleration response and base shear of a building subjected to an earthquake. The base shears of the isolated model varied from 4 percent to 35 percent of those of the fixed base model.

Publisher

University of Illinois Engineering Experiment Station. College of Engineering. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Civil Engineering Studies SRS-578

Type of Resource

text

Language

en

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http://hdl.handle.net/2142/14195

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