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Recent strong seismic events have highlighted the high vulnerability of port facilities resulting in significant physical damages and important socio-economic losses. The most widespread source of seismic damage to port structures is often not related to the ground shaking itself but to the induced phenomena principally associated to the liquefaction of loose, saturated soils that often prevails at coastal areas. In this context, this study aims at the investigation of the influence of soil liquefaction on the seismic performance and vulnerability of typical port gravity quay walls. Different gravity quay wall configurations are examined with varying base width/height ratios. Two-dimensional incremental dynamic analysis is conducted for the soil-quay wall system, under effective stresses using OpenSees software, considering a representative set of fifteen real ground motion records as input ground motion at the bedrock. Two numerical approaches are applied to investigate the effect of liquefaction on its seismic performance and vulnerability assessment: the first one without considering liquefaction, while the second considers the effects of liquefaction. The damage measure is defined in terms of the normalized seaward displacement. Fragility and vulnerability curves are finally derived in terms of different intensity measures and compared with available literature curves. Results show the important role of liquefaction in increasing the seismic vulnerability of the typical port quay wall. [ABSTRACT FROM AUTHOR]

While liquefaction has been widely recognized as being one of the principal earthquake hazards resulting to significant economic and societal losses, research in the vulnerability assessment and quantitative evaluation of the expected physical damages to building structures is rather limited. In this respect, this study aims at the vulnerability assessment of typical low-code reinforced concrete (RC) frame buildings of various heights with shallow flexible foundations subjected to differential permanent displacements due to liquefaction. Nonlinear static analyses are carried out for each considered structural typology assuming different gradually increasing differential displacement patterns applied as quasi-static loads directly at its supports (footings). Different damage mechanisms are examined including a flexural damage of the building members and a shear failure of the columns. The proposed methodology results to the development of lognormally distributed fragility curves for different structural damage states as a function of the liquefaction induced differential displacements. It is shown that the height of the structure as well as the existence or not of a horizontal component of the differential displacements represent key factors affecting the vulnerability assessment. Vulnerability curves are also constructed to assess the expected direct losses in normalised cost terms. The whole approach is illustrated through a specific example. [ABSTRACT FROM AUTHOR]