Earthquake Fragility Assessment of the Underground Tunnel Using an Efficient SSI Analysis Approach

Thai Son Le¹, Jungwon Huh^1*, Jae-Hyun Park²

¹Department of Civil and Environmental Engineering, Chonnam National University, Yeosu, Korea.
²Department of Geotechnical Research Engineering, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea.

DOI: 10.4236/jamp.2014.212123                

Abstract

This paper represents a simplified seismic fragility analysis approach of the underground tunnel structure in consideration of the soil-structure interaction (SSI) effect. SSI effect founds to be essential in the estimation of dynamic analysis of underground structures like tunnels and thus needs to be considered. The ground response acceleration method for buried structures (GRAMBS) known to be a very efficient quasi-static method that can consider SSI effect is used in the proposed approach to evaluate seismic structural responses without sacrificing much accuracy. Seismic fragility curves are then developed by applying the maximum likelihood estimates (MLE) to responses of a large set of artificial ground motion time histories generated for multiple different levels of earthquake intensity. It is also assumed in this paper that the seismic fragility curve can be represented by a two-parameter lognormal distribution function with median and log-standard deviation that need to be defined using MLE.

Keywords

Soil-Structure Interaction, Maximum Likelihood, Fragility Curves, Dynamic Analysis

Conflicts of Interest

The authors declare no conflicts of interest.

References

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