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.

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Angle sections are widely used in civil engineering applications and especially in lattice towers for telecommunication purposes. The principal and geometrical axes of angle sections do not coincide and exhibit very low rigidity when it comes to uniform and non-uniform torsion. Thus, design expressions, e.g. those included in EN1993-1-1 or EN 1993-3-1, do not apply for cross-sections or members composed of angle sections. In addition, limited experimental investigations of members made from angle sections can be found in the literature, and those are mostly for coldformed ones. This paper presents a test campaign involving members made from equal-leg hot-rolled angle sections which was carried out at the Institute of Steel Structures of the National Technical University of Athens (NTUA). Tests included eight three-point bending tests and 31 buckling tests on columns subjected to concentric and eccentric compression. The aims of the research are to use the experimental data for the calibration of numerical models, to investigate possible inelastic reserves in angles which have been detected in analytical models and to serve as a reference for the development of new design expressions oriented towards angle sections only.

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Following the international trends, extensive research on seismic resistant structures has been carried out in Europe during the last decade, with the introduction of several systems with innovative steel-based elements, as the result of European and national research projects. However, these systems have not claimed a fair share of the steel construction market, as provisions for their design have not been included in the Eurocodes and only a few designers are confident enough to employ them. The INNOSEIS project, which has received funding from the Research Fund for Coal and Steel (RFCS) with the participation of 11 partners, aims to deal with this shortcoming. In this paper, the valorisation actions for 12 such innovative anti-seismic devices are presented. Information documents for all dissipative systems have been produced and combined in a single volume, translated in several European languages, for the dissemination to all partners of the construction sector such as architects, structural engineers, construction companies, steel producers and all potential decision makers of the construction sector. Criteria are proposed as to determine which of the systems are characterised as devices and are subject to CE marking in accordance with EN 15129, and which may be considered as innovative systems that require a code approval in EN 1998-1. For the latter, pre-normative design recommendations are drafted that will allow them to receive the status of code-approved systems. A reliability-based methodological procedure to define values of behaviour factors (q-factors) for building structures is proposed, which will be in turn applied to determine q-factors for structural systems with the anticipated systems. A number of case studies with application examples of realistic steel buildings, in which the systems are employed, are presented. Dissemination of the project includes seminars and workshops in several European and Mediterranean countries, as well as the development of online, printed and electronic material, which is free for all people involved in the construction sector, in order to achieve the wide application of innovative seismic resistance systems in practical design.

<p> The new Memaliaj Bridge over the Vjosa River in Southern Albania, with a total length of 123,20m, consists of a continuous, seismically isolated, three-span deck. Due to hydraulic reasons, the central span over the river should be at least 75m long, while the structure had to be economical, easily and rapidly constructible. Thus, the deck is formed by a cast in-situ prestressed concrete box girder, except the 56m of the 76m long central span, which consist of a steel-concrete composite deck, fixed to the concrete part by prestressed tendons and bars. The steel structure was assembled in-situ and erected in five segments, which were put in place by cranes, using the free cantilever method. The application of a composite deck at the central span led to a significant mitigation of the bridge’s self weight and a huge reduction of its construction time.</p>

Innovative dissipative (INERD) Verbindungen für erdbebensichere ausgesteifte Tragwerke aus Stahl werden vorgestellt. Zwischen den Verbandsdiagonalen und den Stützen erfolgt die Verbindung mit Hilfe von Augenstäben und Bolzen. Die Bolzen sind die dissipativen Zonen in diesen Tragwerken, während die anderen Tragwerksteile gegen inelastische Verformungen und Instabilitäten geschützt sind. Das Verhalten der Verbindungen unter monotoner und zyklischer Beanspruchung wurde durch experimentelle und theoretische Untersuchungen studiert. Einfache Regeln zur Bemessung der Verbindung und der angrenzenden Teil e werden vorgestellt.

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