The Site Effect Analysis of Semi-Cylindrical Canyons and Soft Alluvial Basins by H/V Spectral Ratio

Abstract:

The source, path and site effects are the main causes for ground motions. Soft alluvial basins especially result in seismic wave amplification as the site effect. Irregular alluvial basins and canyons in this study are semi-cylindrical for simplifying analysis. To deal with the scattering problems in frequency domain, Yeh et al. have gained positive outcomes by using a hybrid method which combined finite elements and the series expansion method to effectively solve the scattering problem in the irregular basins. These displacements derived from the frequency domain are computed with the H/V ratio to estimate the site effect. As the site effect is crucial in earthquake engineering, this study may serve as a quantitative contribution towards the amplified effect in alluvial basins and canyons. It can also simulate the effects of different incident angles on the H/V ratio.

• Periodical: Applied Mechanics and Materials (Volumes 204-208)
• Pages: 2465-2468
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.204-208.2465
• Online since: October 2012
• Authors: Cheng Chih Chen, Wen Shinn Shyu, Chau Shioung Yeh, Cheh Shyh Ting
• Keywords: Alluvial Basin, Canyon, H/V Ratio, Hybrid Method, P Wave

References

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