The paper investigates the role of soil in the collapse of a 630m segment (Fukae section) of the elevated Hanshin Expressway during the severe Kobe earthquake of 1995. There is evidence that soil-foundation-structure interaction (SFSI) played a detrimental role in the performance of the system. There were 18 spans in total, all of which suffered a spectacular failure and transverse overturning. Several factors associated with poor structural design have already been identified. The scope of this paper is to complement the earlier studies by examining the role of soil in the collapse. Results indicate that the role of soil in the collapse was triple: (1) it modified the bedrock motion so that the frequency content of the resulting surface ground motion became disadvantageous for the particular structure; (2) the compliance of soil and foundation altered the vibrational characteristics of the bridge and moved it to a region of stronger response; (3) ductility demand on the pier was higher than the ductility demand of the system. The increase in seismic demand on the piers may have exceeded 100% in comparison with piers fixed at their base. The above results contradict the widespread view of an always-beneficial role of SFSI.
|Number of pages||10|
|Journal||Geotechnical Special Publication|
|Issue number||126 II|
|Publication status||Published - 1 Dec 2004|
|Event||Geotechnical Engineering for Transportation Projects: Proceedings of Geo-Trans 2004 - Los Angeles, CA, United States|
Duration: 27 Jul 2004 → 31 Jul 2004