True Liquefaction Triggering Curve

Abstract

Current simplified models for predicting liquefaction triggering and manifestation do not account for the mechanisms of liquefaction triggering and surface manifestation in a consistent and sufficient manner. Specifically, an artifact of the way simplified triggering curves have traditionally been developed is that they inherently include some factors that influence surface manifestations, particularly for medium-dense to dense soils. As a result, using the simplified triggering curves in conjunction with the manifestation models results in the double-counting, omission, or general obscuration of distinct factors that influence triggering and manifestation. Accordingly, the objective of this paper is to develop a framework for deriving a true simplified liquefaction triggering model consistent with a defined manifestation model, such that factors influential to triggering and manifestation are handled more rationally and consistently. Operating in conjunction with the LSNish manifestation model, the performance of the true triggering curve is compared with an existing, popular triggering curve using a set of 50 global case histories; the results are favorable for the proposed framework. Furthermore, the ability of the true liquefaction model to be used in conjunction with manifestation models that account for complex free-field soil profile stratigraphies or developed sites is a significant advantage over traditionally developed triggering models.