Seismic fragility functions for embankments on liquefiable soils affected by induced seismicity: application to the Groningen region

Fragility functions are often used to determine earthquake related damage to houses and infrastructures. To be reliable, such fragility functions need to be specific for the structure, the subsoil and the earthquake characteristics. This study derives fragility curves for embankments located on liquefiable soils subjected to induced seismicity in the Groningen region, The Netherlands. The results are based on more than 3000 nonlinear fully coupled dynamic analyses of embankments on liquefiable soils using PLAXIS2D with the PM4Sand model. Both the liquefaction criterion and the input motions used are Groningen-specific and capture the response of embankments under increasing levels of shaking intensity. The fragility curves are developed to evaluate the seismic risk of embankments on liquefiable soil, with the damage states (DSs) described in terms of embankment settlement. The effectiveness of the criteria, including sufficiency, efficiency, practicality, and proficiency, is assessed based on the relationship between intensity measures (IMs) and engineering demand parameters (EDPs). The paper also presents a novel general model that allows for the derivation of fragility curves beyond the specific predefined configurations, providing a more comprehensive analysis. This approach allows for a more holistic understanding of the system’s response and provides valuable insights into the contributions of various intermediate factors.