Bidirectional loading hybrid tests of square cross-sections of steel bridge piers

• Published in: Earthquake engineering & structural dynamics Vol. 42; no. 8; pp. 1111 - 1130
• Main Authors: Dang, Ji, Aoki, Tetsuhiko
• Format: Journal Article
• Language: English
• Published: Chichester Blackwell Publishing Ltd 10-07-2013; Wiley; Wiley Subscription Services, Inc
• Subjects: Acceleration; Bidirectional; bidirectional loading; Bridge piers; Bridges (structures); Displacement; Dynamics; Earth sciences; Earth, ocean, space; Earthquakes, seismology; Engineering and environment geology. Geothermics; Engineering geology; Exact sciences and technology; hybrid test; Internal geophysics; response behavior; Seismic design; square cross-section; steel bridge piers; Structural steels; Far East; Asia; Japan; INW, Japan; steel; cross sections; steel bridge piers; plates; geologic sections; bridges; urban areas; loading; bidirectional loading; response behavior; acceleration; seismic response; square cross-section; hybrid test; piers; displacements; highways; earthquake engineering; performances; direction
• ISSN: 0098-8847; 1096-9845
• DOI: 10.1002/eqe.2262

SUMMARY
Steel rectangular section columns with stiffened plates are commonly used for elevated highway bridges in the urban areas of Japan. The seismic design of bridge piers is usually performed by dynamic analysis in the horizontal direction using various independent directional seismic acceleration data. However, this simple treatment does not reflect the effect of bilateral loading as a structural response to inelastic interaction. In this study, unidirectional and bidirectional loading hybrid tests were conducted to examine the seismic response and performance of square cross‐sections of steel bridge piers subjected to bidirectional seismic accelerations. Comparison of the results of unidirectional and bidirectional loading tests revealed that the maximum load is the same as the average of unidirectional loading in the NS and EW directions; however, the maximum response displacement and residual displacement increase in proportion with hard to soft ground types. Moreover, a modified seismic design is proposed considering these bidirectional loading effects. Copyright © 2012 John Wiley & Sons, Ltd.