Analysis of Deformation and Failure of Embankment Slope Under Earthquake

Abstract

Earthquakes are among the natural factors that seriously threaten the development of human society and the economy. Earthquakes significantly threaten embankment slope stability, with dynamic responses influenced by seismic wave characteristics, slope geometry, and material properties. This study uses FLAC3D numerical simulation to analyze acceleration, displacement, and stress responses of a mountainous embankment slope under Wolong (WL), Lushan (LS), and Luding (LD) seismic waves. Innovations include the first comparative evaluation of three seismic waves’ differential effects, revealing LD waves induced the strongest acceleration amplification (1.5–2 times the slope toe values, 0.1–0.2 s time lag) while LS waves caused the highest stress increments (LS > LD > WL). A validated local damping model (0.157) combined with free-field boundary conditions improved seismic wave propagation simulation accuracy. Significance lies in providing multi-wave design criteria for seismic zones, validating the Mohr-Coulomb model’s applicability to soil elastoplastic behavior, and guiding monitoring strategies. Conclusions show seismic wave type dominantly controls responses, with crest stress mutations (−123%) and mid-slope displacement sensitivity (7.5 mm at 0.5 g) indicating instability risks. The model offers a reliable framework for slope seismic design in complex geological settings.