ABSTRACT Recently, occurrence of repeated shaking events such as the Kobe earthquake (1995), the Wenchuan earthquake (2008), the Chi-Chi earthquake (1999) and the Kumamoto earthquake (2016), Kahramanmaras earthquake (2023), etc., posed a severe threat to the safety of infrastructures. Studies on the influence of repeated shaking events on underground structures are minimal. Considering the above, tunnel-soil interaction under repeated shaking events is attempted in the study. One-gram shaking table tests were conducted in this study by varying loading frequency (5 Hz, 10 Hz) and tunnel embedment depth (H/W − 0.85 and 1.2 where H is the tunnel embedment depth and W is the width of the tunnel) and subjected to incremental shaking conditions, i.e. 0.2 g, 0.3 g and 0.4 g. A tunnel-embedded ground with 60% relative density was prepared and instrumented with conventional sensor schemes and a non-contact-based 2D digital image correlation technique. It was observed that the loading frequency and tunnel embedment influences tunnel’s performance during repeated shaking events. About 37% to 62.4% increment in tunnel displacement was observed in the case of H/W-0.85, and 20% to 29% increment in tunnel displacement was observed for H/W-1.2 when subjected to incremental acceleration shaking, i.e. 0.2 g to 0.4 g for varying embedment depth conditions.
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