FINITE ELEMENT ANALYSIS OF SELF-CENTRING BEAM-TO-COLUMN SUBASSEMBLIES IN SEISMIC-RESILIENT STEEL MRF: PRELIMINARY EVALUATION OF THE FRAME EXPANSION EFFECTS

Conventional code-based seismic design methods widely applied worldwide rely on the dissipation of seismic energy through construction damage. While this approach ensures life safety, it often results in significant post-earthquake damage, leading to substantial direct and indirect losses that affect communities’ resilience. To overcome these limitations, modern Earthquake Engineering is focusing on developing high-performance, cost-effective structures capable of withstanding design-level earthquakes with minimal socio-economic impact. In this context, the ERIES - SC-RESTEEL (Self-Centring seismic-RESilient sTEEL structures) project explores the structural response, repairability, resilience, and performance recovery of a steel self-centring Moment-Resisting Frame (MRF) incorporating friction devices and post-tensioned bars at column bases and beam-to-column joints. The project includes full-scale shaking table tests on a three-storey steel MRF at LNEC (Laboratório Nacional de Engenharia Civil) in Lisbon, Portugal. Moreover, the project investigates the response of the beam-to-column joint and the effect of the frame expansion due to the rocking of the beams through quasi-static cyclic tests on MRF subassemblies in Salerno, Italy. This paper illustrates the preparatory numerical work, including advanced Finite Element (FE) models in ABAQUS considering two configurations of the subassemblies, and investigates a solution to mitigate the frame expansion effects. The combined FE and experimental results provide crucial insights into the design of shaking table tests and the expected experimental outcomes.