Numerical and Empirical Assessment of Liquefaction-Induced Settlement and Uplift from Field Evidence

Liquefaction-induced ground deformations constitute a major source of earthquake-related damage, affecting both surface structures and buried infrastructure systems. This study presents a comparative assessment of two complementary case histories supported by advanced numerical modeling, semi-empirical procedures, remote sensing data, and post-earthquake field observations. Free-field settlements following the 2011 Christchurch earthquake were evaluated using UBC3D-PLM and PM4Sand constitutive models and compared with semi-empirical approaches based on SPT and CPT data. Numerical predictions were further compared with LiDAR-derived surface deformation measurements. The UBC3D-PLM model predicted a settlement of 3.5 cm, whereas the PM4Sand model estimated 8.8 cm. Semi-empirical methods yielded settlements of approximately 11 cm, consistent with LiDAR-observed surface deformations ranging between 10 cm and 20 cm. The comparison illustrates the sensitivity of predicted settlements to constitutive formulation and reconsolidation modeling assumptions. The uplift behavior of a stormwater pumping station in Iskenderun during the 2023 Kahramanmaraş earthquake was analyzed using the UBC3D-PLM model. Numerical simulations predicted an uplift of approximately 28 cm, in close agreement with field observations of about 30 cm, demonstrating the capability of effective-stress-based constitutive modeling to capture soil–structure interaction effects under liquefied conditions. The findings highlight that surface settlements and structural uplift represent complementary manifestations of post-liquefaction ground response. Comparative evaluation underscores the influence of modeling approach and assumptions on predicted deformation levels. By examining numerical, empirical, and field-based evidence across two case histories, this study provides insight into the capabilities and limitations of current methods for estimating liquefaction-induced ground deformations and supports more informed assessment of infrastructure performance in liquefaction-prone regions.