PLT - Numerical Evaluation of Anti-Liquefaction Performance of Deep Soil Mixing Method under Embankment Dams

One of the most catastrophic results of earthquakes is liquefaction-induced failure of earth structures such as embankment dams. In previous liquefaction-induced earth embankment failures, a significant amount of excess pore water pressure (EPWP) was generated in the liquefied area and gradually expanded inside the geo-structure, leading to failure. This issue necessitates the application of appropriate liquefaction remediation countermeasures for embankment dam safety. In this paper, the anti-liquefaction performance of the deep soil mixing (DSM) method beneath the embankment dams was investigated numerically in FLAC3D. The validity of the developed model was evaluated using the centrifuge experiments of the VELACS project. Analyses were carried out under various parameters such as the diameter and length of DSM columns. The effects of depth and relative density of the liquefiable soil layer, and input motion on the seismic response of the embankment dam were studied as well. Valuable insights into the dynamic behavior of the employed DSM columns under embankment dams were provided. It was concluded that DSM columns could effectively mitigate liquefaction under the embankment dams. By increasing the length and diameter of DSM columns, the liquefaction-induced EPWP generation was reduced considerably. Furthermore, the DSM columns have better performance at moderate relative density and moderate input acceleration. The obtained results can be a useful tool in the seismic design of embankment dams.