Anti-liquefaction Performance of Stacked Sandbags: Shaking Table Tests and Numerical Simulations

Abstract

Stacked sandbags are popularly used as building foundations and reinforcing slopes because of their high compression bearing capacity. However, their anti-liquefaction performance under seismic vibrations has not been well studied before. This paper carefully explored the anti-liquefaction performance of stacked sandbags by shaking table tests and numerical simulations. The testing results prove that the pore-water pressures and excess pore pressure ratios inside stacked sandbags were much lower than those of a traditional sand foundation. The deeper the sandbag is, the lower the pore-water pressure is. Therefore, stacked sandbags have evident anti-liquefaction performance. The simulated results prove that the effective stresses of the sand inside the sandbags were substantially higher, and the tensile stresses of the sandbag packages play an essential role in the anti-liquefaction performance. The greater tensile stress inside the sandbag results in better anti-liquefaction performance, and the anti-liquefaction performances at the bag edges are better than those at the center places. The elastic modulus and thickness of the bags are also beneficial for anti-liquefaction performances. Furthermore, because of the tensions of the packages, the sand shows shear dilation, not a shear contraction, under horizontal vibrations, especially at the edges of sandbags. The simulated results show that the settlements of the stacked sandbags are small and evenly distributed during the vibration. Therefore, stacked sandbags are appropriate for buildings and slopes located in seismic areas.