Remote Boundary for Numerical Simulations of Soil Slope Response to Earthquakes

Accuracy of numerical simulations of seismic response of soil slopes is influenced by the choice of boundary conditions. We used a finite element model, field records of ground motion, and two sets of generalized slope models to examine slope dynamics and identify optimal dimensions for the leading and trailing edges of slope models. To avoid superposition of seismic waves reflected by model boundaries, our results show that the length of the leading edge of the model should exceed two times slope height and the length of the trailing edge should exceed four times slope height. These dimensions would ensure the accuracy of simulation results. The difference between the seismic safety factor for a slope with viscoelastic boundaries and that for a slope with remote fixed boundaries is 0.02, which validates the applicability of remote fixed boundaries to analyses of slope seismic stability.