RFSR‐CT‐2013-00021 EQUALJOINTS

European pre-QUALified steel JOINTS
Starting date: 01/07/2013
Duration: 36 months
Ending date: 30/06/2016

Partners

Description

This research project is concerned with the pre-qualification of all-steel Beam-to-Column joints in steel structures and it is aimed at introducing a codified practice currently missing in Europe. Although other research investigations have been early carried out on the seismic behaviour of steel Beam-to-Column joints at European level, none was aimed at prequalifying specific configurations on the basis of parametric experimental investigations. This is mainly evident in the case of dissipative beam-to-column connections, where many issues still remain open. At the present time, there are no reliable design tools able to predict the seismic performance of dissipative Beam-to-Column connections in order to meet code requirements. With this regard, EC8 prescribes design supported by experimental testing, which results in impractical solutions within the time and budget constraints of real-life projects. On the other hand, also for full-strength joints reliable design tools are necessary. Since, due to the variability of steel strength, these connections could not provide enough overstrength and in such cases their plastic rotation capacity must be prequalified by relevant test and numerically based procedures. The use of prequalified joints is a common practice in US and Japan. Nevertheless, the standard joints prequalified according to codified procedures in US and Japan cannot be extended to Europe. The proposed research project aims to fill all these gaps. This project is planned and finalized as a pre-normative research aiming to propose relevant criteria for the next version of EN 1998-1. In detail, the research will focus on the standardization of design and manufacturing procedures on the basis of different geometric and mechanical parameters of selected joint typologies. Hence, a large experimental programme supported by theoretical and numerical analyses is proposed to provide reliable standard joints that can be easily used by designers.

Working Packages (WP)

WP1: Selection and design of joint typologies
This WP is devoted to the selection and to the design of the joints to be qualified. The joint typologies will be selected according to the common European practice and so as to be compatible with different structural systems and the sizes of framing elements (moment resisting frames and dual frames).
WP2: Analytical Models
The objective of WP2 is to provide analytical tools for the characterization of beam-to-column joints subjected to cyclic loading. Design guidance for the use of partial strength dissipative joints in seismic regions will be provided.
WP3: Numerical Tests
The research activity of WP3 is devoted to provide the preliminary tools to design the experimental activity (as the test lab setup) and the interpretation of experimental results, as well. Finite element analyses will be performed before the execution of experimental tests in order to investigate the key parameters affecting the joint response and to design the test setup.
WP4:  Experimental Tests
The aim of WP4 is to perform tests on a set of typical steel joints selected and designed by WP1. Experimental tests will be performed in order to demonstrate both the effectiveness and the reliability of the designed joint detailing under seismic/wind simulated loading.
WP5: Design tools
Following the results of WP2, WP3 and WP4 activities, WP5 will collect the main achieved results and will define the design guidelines also on the basis of extensive back analysis. Moreover, this WP will include the recommended detailing of each investigated joint typology, the design methodology and relevant design criteria.
WP6: Coordination, management and dissemination
WP6 has the fundamental role of planning, managing and coordinating the research activities. In particular, this WP has to evaluate the progress of the research. It will also involve disseminating the output of the projects.

Research Team at DiSt

Raffaele Landolfo – landolfo@unina.it
Mario D'Aniello – mdaniel@unina.it
Francesco Portioli – fportiol@unina.it
Lucrezia Cascini – lucrezia.cascini@unina.it
Giuseppe La Manna Ambrosino – giuseppe.lamannaambrosino@unina.it
Silvia Costanzo – silvia.costanzo@unina.it