Upgrading seismic performance of underground frame structures based on potential failure modes. Issue 153 (February 2022)

• Record Type: Journal Article
• Authors: Wu, Chunyu; Lu, Dechun; El Naggar, M. Hesham; Ma, Chao; Li, Qiang; Du, Xiuli
• Is Part Of: Soil dynamics and earthquake engineering. Issue 153(2022)
• Publication Date: 2022-02
• Subjects: Upgrading seismic performance -- Underground frame structures -- Potential failure mode -- Failure mechanism -- Retrofitting scheme; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2021.107116
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: Most subway stations in China have been constructed recently and their seismic performance and potential failure modes are not well characterized. This paper is dedicated to identifying potential failure modes of underground frame structures through numerical simulations, and developing an optimized method for upgrading the seismic performance of deficient structures via controlling the potential failure modes. The dynamic response of an unequal-span subway station structure was calculated considering different ground motions with increasing peak horizontal acceleration, and the structural seismic performance characteristics were evaluated. Seismic performance evaluation indexes, including interlaminar deformation risk factor of columns and sidewalls and deflection risk factor of slabs, were established to identify the most critical structural component under strong earthquake excitations. The structure failure mechanism was analyzed, and consequently, the corresponding retrofitting scheme for upgrading its seismic performance was proposed. Finally, the structural responses before and after retrofit were calculated and compared to demonstrate the effectiveness of the retrofitting scheme. The results can improve the understanding of the failure modes of underground frame structures and provide references for their seismic design. Highlights: Deflection deformability of slabs is included in seismic evaluation indexes for underground structures. Seismic performance upgrading approach based on potential failure modes is proposed. Potential failure mode of an unequal-span subway station is identified and its failure mechanism is revealed. The retrofitting scheme for preventing potential failure mode improves seismic performance of an unequal-span structure.