Seismic Performance of Steel MRFs Designed to the Provisions of the Latest Draft Eurocode 8: Case Studies

Various improvements have been proposed to the seismic code Eurocode 8 in recent years. In its current state, the norm under revision has been expanded in content and structure. Modifications in the definition of ductility classes, behaviour factors, inter-storey drift sensitivity (ISDS) coefficient, the local hierarchy criteria, and the design rules for medium (DC2) and high ductility class (DC3) structures are a few of the notable changes to be mentioned for the design of steel moment-resisting frames (MRFs). In MRFs, which are highly susceptible to lateral deformations, design is often governed by stability requirements in the verification of the significant damage limit state. This leads to the use of heavier sections in members to meet the lateral stiffness demand. In the computation of ISDS, the draft code takes advantage of the design over-strength ratio and the material variability in the dissipative zones. This paper aims to study and compare seismic designs of MRFs using the revised specific rules for steel design in the new code which is now at a working draft level. The flexibility achieved due to the mentioned considerations is first studied through case study frames. Once designed, the performance of these frames is examined through non-linear analyses using OpenSees.