Cyclic behaviour of steel beam‐to‐column joints and calculation tools

Abstract

The seismic design of dissipative beam‐to‐column steel joints is currently allowed in Eurocode EN1998 only when supported by tests due to the lack of reliable models for predicting their behaviour under cyclic conditions. On the other hand, the well‐known component method coded in EN 1993‐1‐8 (EC3‐1‐8) only applies to monotonic response of the joints. In this paper, an extension of this method, cyclic component method (CCM), is presented, which was developed and implemented for cyclic conditions in the scope of the research project EQUALJOINTS. The CCM was developed to predict the joints moment‐rotation behaviour for a wide range of joint configurations by properly combining cyclic force‐elongation behaviour of relevant components using the Modified Richard‐Abbott model. The step‐by‐step development and implementation of the CCM addresses (i) widespan variety of joint configurations and (ii) is fully compatible with the prescriptions in EC3‐1‐8. An example of application of the method is shown for an end‐plate beam‐to‐column steel beam‐to‐column joint, highlighting the level of accuracy achieved so far in the simulations of the cyclic behaviour of joints. The work performed so far shows promising results and good perspectives for new developments, which are identified making use of evidence from the results of the application example.