A geotechnical seismic isolation system based on marine sand cushion for attenuating ground shock effect: Experimental investigation. Issue 168 (May 2023)

• Record Type: Journal Article
• Authors: Zhang, Haotian; Song, Chunming; Wang, Mingyang; Cheng, Yihao; Yue, Songlin; Wu, Chunyao
• Is Part Of: Soil dynamics and earthquake engineering. Issue 168(2023)
• Publication Date: 2023-05
• Subjects: Geotechnical seismic isolation -- Marine sand -- Ground shock -- Isolation mechanism -- Storage tank; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2023.107854
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: In this paper, an experimental study is introduced on the feasibility of applying a geotechnical seismic isolation system based on marine sand cushion (GSI-MSC) to resist explosion-induced ground shocks. The isolation system is characterised by low cost, easy availability, and slippage limitations, and it is particularly suitable in the protection of engineering structures during emergencies. Laboratory experiments on a steel tank structure were performed using a self-developed explosion shock and vibration simulation platform. The attenuation effects of the isolation system on ground motion, superstructural vibration and structural deformation were analysed. The results showed that GSI-MSC can reduce the intensity of ground shock, decrease the amplification effect of structural vibration, and weaken structural deformation. The attenuation effects were significantly enhanced with an increase in sand cushion thickness. The isolation mechanism was revealed from the perspective of spectrum analysis. The decreased lateral stiffness and reduced damping ratio improved the soft layer effect and internal energy dissipation of the sand cushion. This in turn led the GSI-MSC to exhibit a better harmonic attenuation effect over a wider range of high frequencies, beginning at a lower threshold. After isolation, the principal frequency of the ground motion decreased while the amplitude of high-frequency harmonics decreased, resulting in the weakening of the superstructural dynamic response. This indicated that the isolation system has a more stable attenuation effect on the low-period structures. Highlights: Conduct a feasibility study of applying GSI-MSC for attenuating ground shock effect. Carry out laboratory experiment via a self-developed explosion shock and vibration simulation platform. Investigate the attenuation effects of GSI-MSC on ground motion and superstructural response. Sensitivity analysis of sand cushion thickness. Reveal the ground shock attenuation mechanism.