Seismic response of steel frames with reduced beam sections

This study concerns the effectiveness of weakening on the beams of fully and partially restrained connection steel frames in order to locate plastic hinges far from the joints. Two types of non-linearanalysis, for geometry and constitutive law are developed: static pushover analysis, in which the structure is subjected to constant vertical loads and to horizontal loads linearly increasing up to collapse; and incremental dynamic analysis, in which the structure is subjected to uniformly scaled ground motions. Applications forfour-bay frames with three and nine stories designed according to the EC3 code and for Italian 1st-category seismic areas are developed in order to evaluate the influence of building height on the validity of the proposed improvement solution.