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The stress-based simplified liquefaction triggering procedure is the most widely used approach to assess liquefaction potential worldwide. However, empirical aspects of the procedure were primarily developed for tectonic earthquakes in active shallow-crustal tectonic regimes. Accordingly, the suitability of the simplified procedure for evaluating liquefaction triggering in other tectonic regimes and for induced earthquakes is questionable. Specifically, the suitability of the depth-stress reduction factor (rd) and magnitude scaling factor (MSF) relationships inherent to existing simplified models is uncertain for use in evaluating liquefaction triggering in stable continental regimes, subduction zone regimes, or for liquefaction triggering due to induced seismicity. This is because both rd,which accounts for the non-rigid soil profile response, andMSF,which accounts for shaking duration, are affected by the characteristics of the ground motions, which can differ among tectonic regimes, and soil profiles, which can vary regionally. Presented in this paper is a summary of ongoing efforts to regionalize liquefaction triggering models for evaluating liquefaction hazard. Central to this regionalization is the consistent development of tectonic-regime-specific rd and MSF relationships. The consistency in the approaches used to develop these relationships allows them to be interchanged within the same overall liquefaction triggering evaluation framework. 

The severity of surface manifestation of liquefaction is commonly used as a proxy for liquefaction damage potential. As a result, manifestation severity index (MSI) models are more commonly being used in conjunction with simplified stress-based triggering models to predict liquefaction damage potential. This paper assesses the limitations of four MSI models. The different models have differing attributes that account for factors influencing the severity of surficial liquefactionmanifestations, with the newest of the proposed models accounting more factors than the others. The efficacies of these MSI models are evaluated using well-documented liquefaction case histories from Canterbury, New Zealand, with the deposits primarily comprising clean to non-plastic silty sands. It is found that the MSI models that explicitly account for the contractive/dilative tendencies of soil did not perform as well as the models that do not account for this tendency, opposite of what would be expected based on the mechanics of liquefaction manifestation. The likely reason for this is the double-counting of the dilative tendencies ofmedium-dense to dense soils by theseMSI models, since the liquefaction triggering model, to some extent, inherently accounts for such effects. This implies that development of mechanistically more rigorous MSI models that are used in conjunction with simplified triggering models will not necessarily result in improved liquefaction damage potential predictions and may result in less accurate predictions.