Relationships Between Ground-Motion Intensity Measures and Earthquake-Induced Permanent Slope Displacement Based on Numerical Analysis

In engineering applications, the permanent displacement (D) commonly serves as a useful indicator of the seismic performance of slopes. When developing empirical displacement models as a function of ground-motion intensity measures (IMs), the IMs that are best correlated to D are preferred. On the other hand, the predictability of IMs, in terms of the standard deviations using ground motion models, is also of concern in developing D models. This study aims to: (1) investigate the efficiency of IMs in developing D models for a cohesive-frictional slope based on numerical analysis; and (2) compare the means and standard deviations of randomized D by considering uncertainties in predicting both the IMs and D via Monte Carlo simulation (MCS). A total of 10 scalar IMs and 38 vector-IMs, are employed to develop D models. The results indicate that the spectral acceleration at a degraded period of the soil layer (SA(1.5T_s,layer)) and Arias intensity (IA) are the two most efficient scalar IMs. Additionally, the vector-IMs consisting of [IA, spectrum intensity] and [IA, mean period] are the two most efficient vectors. The MCS results illustrate that the rankings for standard deviations of D models and total standard deviations (i.e., including ground motion variability) may be considerably different. The results are also found to be dependent on earthquake magnitudes and site conditions. This study could provide guidance on the development of numerical-based D models especially within a probabilistic seismic slope displacement analysis framework.