Location

San Diego, California

Session Start Date

5-24-2010

Session End Date

5-29-2010

Abstract

This paper presents a new seismic design philosophy, which under-designs the foundation to act as a “fuse” in case of strong seismic shaking. A simplified bridge pier is used to illustrate the advantages and disadvantages of this new philosophy compared to conventional capacity design. For this purpose, two alternatives are compared : one with an over-designed foundation, in accordance with conventional capacity design (so that the plastic “hinge” develops in the superstructure), and one with under-designed foundation. The performance of the two alternatives is investigated through shaking table testing of reduced scale models, using real accelerograms and artificial sinusoidal motions. It is shown that the performance of both alternatives is acceptable for moderate seismic shaking. For larger intensity ground motions, that clearly exceed the design limits, the performance of the new design concept is advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. The price to pay is mainly the increase of seismic settlements, and in some cases of permanent foundation rotation.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Meeting Name

Fifth Conference

Publisher

Missouri University of Science and Technology

Publication Date

5-24-2010

Document Version

Final Version

Rights

© 2010 Missouri University of Science and Technology, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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May 24th, 12:00 AM May 29th, 12:00 AM

Experimental Soil - Foundation - Bridge Pier Interaction : Towards a Reversal of Capacity Design

San Diego, California

This paper presents a new seismic design philosophy, which under-designs the foundation to act as a “fuse” in case of strong seismic shaking. A simplified bridge pier is used to illustrate the advantages and disadvantages of this new philosophy compared to conventional capacity design. For this purpose, two alternatives are compared : one with an over-designed foundation, in accordance with conventional capacity design (so that the plastic “hinge” develops in the superstructure), and one with under-designed foundation. The performance of the two alternatives is investigated through shaking table testing of reduced scale models, using real accelerograms and artificial sinusoidal motions. It is shown that the performance of both alternatives is acceptable for moderate seismic shaking. For larger intensity ground motions, that clearly exceed the design limits, the performance of the new design concept is advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. The price to pay is mainly the increase of seismic settlements, and in some cases of permanent foundation rotation.