FUNDAMENTAL MODAL BEHAVIOR OF AN EARTHQUAKE-EXCITED BRIDGE.

A. G. Brady; M. Çelebi

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USGS · 70014563

FUNDAMENTAL MODAL BEHAVIOR OF AN EARTHQUAKE-EXCITED BRIDGE.

A. G. Brady·M. Çelebi

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Abstract

The magnitude 6. 1 Morgan Hill, California, earthquake of April 24, 1984, produced a set of acceleration records at the freeway overpass in San Jose carrying I-280/I-680 across U. S. 101, 12 km from the epicenter. Peak accelerations reached 0. 10 g at ground level and 0. 16 g in the box girder. The integrated displacements at frequencies higher than 3 Hz permit the identification of the fundamental modes and frequencies. The horizontal modes have frequencies of 308 and 3. 9 Hz and include ground level motions up to 90% of peak deck motion. The soil-structure system contributes to these modes.

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A. G. Brady, M. Çelebi. 1986. FUNDAMENTAL MODAL BEHAVIOR OF AN EARTHQUAKE-EXCITED BRIDGE.. https://pubs.usgs.gov/publication/70014563

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