Statistical numerical method for determining seismic performance and fragility of shallow-buried underground structure

• Published in: Tunnelling and underground space technology 2021-10, Vol.116, p.104090, Article 104090
• Main Authors: Zhuang, Haiyang, Yang, Jing, Chen, Su, Dong, Zhengfang, Chen, Guoxing
• Format: Article
• Language: English
• Subjects: Buried structures; Damage assessment; Earthquake damage; Earthquakes; Fragility; Ground motion; Intensity measure; Lateral displacement; Mathematical models; Numerical analysis; Numerical methods; Seismic engineering; Seismic fragility curves; Seismic performance; Seismic response; Soil structure; Statistical numerical modeling; Subway stations; Underground construction; Underground structure; Underground structures
• ISSN: 0886-7798; 1878-4364
• DOI: 10.1016/j.tust.2021.104090

•The soil–underground structure interaction model was developed and verified simply.•A method for determining seismic performance and fragility of underground structure was established.•A comparative evaluation of the different IMs for underground structures was carried out. Currently, research on the underground structures seismic fragility is still in its infancy state. In this study, we carried out numerical simulation on soil-underground structure system (SUSI) by taking the Daikai metro station damaged in the Kobe earthquake as analysis object. Considering input ground motion characteristics, based on incremental dynamic analysis (IDA method), a statistical numerical modeling method was established to classify underground structure seismic damage status and its seismic performance level. The analysis results showed that the input ground motions had a significant effect on the IDA curves. The rationality and randomness of the selected ground motions were important influencing factors to ensure the underground structures seismic fragility curves. In relation to the damage that occurred to the Daikai station in 1995, the peak ground acceleration (PGA) and peak relative lateral displacement (PRLD) of the site were suitable for estimating the seismic performance of the shallow buried structure constructed. Finally, the seismic fragility curves were compared with the existing research results, and a seismic damage assessment was carried out, which verified the effectiveness of the statistical numerical modeling method developed in this study.