1-G SHAKING TABLE TESTS ON THE DYNAMIC RESPONSES OF A SATURATED FIELD UNDER CONSECUTIVE EARTHQUAKES

A 1-g shaking table test was conducted to investigate the dynamic responses of a saturated sandy field under various seismic loadings. To ensure appropriate boundary conditions and uniformity of the sand specimen, a laminar shear box and sand pluviator were employed. The findings reveal that the occurrence of ground liquefaction is more pronounced during high-frequency shakings, highlighting a strong correlation between field acceleration mitigation and the accumulation of pore water pressure. In contrast, during low-frequency events, excess pore pressure undergoes significant fluctuations before progressing into the full-liquefaction stage. The subsequent re-liquefaction behaviors were also analyzed, revealing a heightened liquefaction resistance following each loading event, primarily attributed to the dominant impact of field densification. Furthermore, the frequency characteristics of the specimen were evaluated before and after consecutive shaking events. The results indicate an increase in the fundamental frequency in both directions after the shakings, albeit with a slightly smaller increment observed in the loading direction.##################################################