# Fragility Assessment of Traffic Embarkments Exposed to Earthquake-Induced Liquefaction
## 1 Introduction
In addition to the different EDPs, fragility curves have been derived as a function of various IMs in these studies, such as with peak ground velocity [12], pseudostatic horizontal acceleration [13] and the more commonly used peak ground acceleration (PGA) [14; 15; 16]. In a slightly different context to earthquake-induced deformations of road embankments, [PERSON] and co-authors [17] studied the impact of groundwater level within the embankment and the size of scour at the toe of the embankment on the fragility curves, where the IM was defined as a function of embankment height and groundwater level, while crest settlements were taken as EDP. Different approaches have been developed for the derivation of fragility curves, including empirical, analytical, expert judgement and hybrid methods [18]. Empirical fragility curves are based on extensive datasets from past earthquakes at locations with similar characteristics. The main problem with this approach is a lack of observed-damage surveys on particular objects under consideration for various seismic loading intensities. It is only appropriate for specific cases, and is not suitable for general situations. However, it does allow for soil-structure interaction to be observed in a more realistic way, compared to the other approaches, because local effects in the ground can be detected by advanced on-site measuring devices. In addition to the empirical method, rapid fragility-curve estimation can be achieved using expert judgement. This approach is convenient for an initial guesstimate of the situation only, since huge deviations among different experts are expected. On the other hand, use of the analytical method has been gaining popularity, with the improvement of computer and software capabilities, because it enables analysis of the same problem under different boundary and seismic loading conditions. The method allows a rigorous consideration of local seismological conditions. Nevertheless, all analytical (numerical) procedures are affected by modelling uncertainties, which means that all predictions are just an approximation of the reality. When one of the above methods cannot sufficiently cover the entire range of a fragility curve, the so-called hybrid method is used, in which several approaches are combined. The following sections present a more detailed description of the methodologies used for the derivation of fragility curves, a description of the model geometries, soil parameters and input ground motions (GMs), and the final outcomes of the analyses. The main aim of the study is to show the influence of different model variables on the response of an embankment built on liquefiable ground in terms of fragility curves. The study follows a known methodology for the derivation of fragility curves. Fragility of embankments considering earthquake-induced liquefaction has rarely been addressed by researchers. The contribution of [PERSON] et al. [16] studied the influence of isotropic and anisotropic permeability of the ground on the embankment response in terms of fragility curves. In our study, the influence of ground and embankment geometry (thickness of liquefiable layer, presence of crust layer and height and width of embankment) and of the relative density of the liquefiable layer on fragility curves was investigated.