Response of indeterminate two-span beam to spatially varying seismic excitation

✍ Scribed by Ronald S. Harichandran; Weijun Wang

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 742 KB
• Volume: 19
• Category: Article
• ISSN: 0098-8847
• DOI: 10.1002/eqe.4290190203

✦ Synopsis

In order to examine the effect of the spatial variation of ground motion on the response of an indeterminate structure, the stochastic responses of a two-span beam to spatially varying support excitations are analysed. A space-time earthquake ground motion model that accounts for both coherency decay and seismic wave propagation is used to specify the support motions, and the results are compared with those for various simplified excitations that are commonly used in practice. The response is computed through a linear random vibration approach with the structure being modelled by finite elements. The results of the study indicate that, even for moderate lengths, the effect of the spatial variation of ground motion can be significant. The assumption of fully coherent support motions (same excitations at all supports or delayed excitations allowing only for wave propagation) may be overconservative for some beams and unconservative for others.

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