Shaking table tests using geotechnical centrifuge to investigate non-linear behavior of liquefiable ground during large earthquake
Shaking table tests using geotechnical centrifuge to investigate non-linear behavior of liquefiable ground during large earthquake
In Japan, a Nankai Trough megathrust earthquake is predicted to occur in the near future. If such an earthquake, with large acceleration amplitudes and a high proportion of long-period components, were to occur, non-linear behavior of ground such as strain-dependent stiffness reduction and liquefaction, which significantly affect the seismic responses of buildings and underground structures, would occur. In 2024, a new geotechnical centrifuge was introduced at our research facility, and the shaking table equipped with the centrifuge can reproduce large-amplitude and long-period seismic motion. Therefore, we conducted shaking table tests on dry and saturated sandy soil with medium and high density to investigate the non-linear behavior of sandy soil during the large earthquake. In the case of dry sand, the results of the tests indicate that shear strain and stiffness-reduction rate during an earthquake increases as relative density decreases. In the case of saturated sand, the possibility of liquefaction occurrence at depths deeper than G.L.-20m is verified and the generation of pulsed acceleration due to cyclic mobility is notably evident in the high-density case. Furthermore, we conducted reproduction simulations using FEM for both cases. The results of the simulations generally agree with the results of the tests. In particular, for the simulations targeting saturated sand, incorporating groundwater movement enables reproduction of the development and dissipation processes of excess pore water pressure during long-duration earthquakes such as the input wave in these tests.
Hiromasa Iwai; Yasuhiro Ikami; K. Shibata; HIROKI UNO; H. Funahara; T. Fujiwara; Sadayuki Ishizaki
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 10: Liquefaction Experiments and Analysis Projects – Lesson Learned from LEAP-Asia-2025
https://doi.org/10.53243/ICPMG2026-90