This study focusses on the estimation of seismic fragility curves for all common bridge types found in modern greek motorways. At first a classification scheme is developed in order to classify the existing bridges into a sufficient number of classes. A total of 11 representative bridge classes resulted, based on the type of piers, deck, and pier-to-deck connection. Then an analytical methodology for deriving fragility curves is proposed and applied to the representative bridge models. This procedure is based on pushover analysis of the entire bridge and definition of damage states in terms of parameters of the bridge pushover curves. The procedure differentiates the way of defining damage according to the seismic energy dissipation mechanism in each bridge, i.e. bridges with yielding piers of the column type and bridges with bearings (with or without seismic links) and non-yielding piers of the wall type. The activation of the abutment-backfill system due to closure of the gap between the deck and the abutments is also taken into account. The derived fragility curves are subjected to a first calibration against empirical curves based on damage data from the US and Japan.

No abstract

This is the accepted version of the paper.This version of the publication may differ from the final published version. The paper presents a methodology for evaluating the 'actual' response modification factors (q or R) of 4 bridges, and applies it to seven concrete bridges typical of the stock found in Southern Europe. The 5 usual procedure for analytically estimating the q-factor is through pushover curves derived for the 6 bridge in (at least) its longitudinal and transverse direction. The shape of such curves depends on the 7 seismic energy dissipation mechanism of the bridge; hence, bridges are assigned to two categories, 8 those with inelastically responding piers and those whose deck is supported through bearings on 9 strong, elastically responding, piers. For bridges with yielding piers the final value of the q-factor is 10 found as the product of the overstrength-dependent component (q s ) and the ductility dependent 11 component (q μ ), both estimated from the pertinent pushover curve; for bridges with bearings and non-12 yielding piers of the wall type an equivalent q-factor is proposed, based on spectral accelerations at 13 failure and at design level. In this paper pushover curves are also derived for an arbitrary angle of 14 incidence of the seismic action using a procedure recently developed by the authors, to investigate the 15 influence of the shape of the pushover curve on the estimation of q-factors. It is found that in all cases 16 the available force reduction factors were higher than those used for design either to Eurocode 8 or to 17 AASHTO. 18 Permanent repository link

No abstract

Keywords:Pressure vessels, pushover analysis, vulnerability and fragility assessment, surrogate models. Abstract