Uso de marcos con riostras intencionalmente excéntricas en edificios de gran altura.

Frames with Intentionally-Eccentric Braces (FIEBs) are a novel seismic-force-resisting system that overcomes the limitations of concentrically braced frames related to their high elastic stiffness and marginal post-elastic stiffness. Recent studies have shown that FIEBs offer an improved seismic performance and require less material than concentrically braced frames in low- and mid-rise buildings owing to their high post-elastic stiffness and to a better control over the overstrength. Another presumed advantage of FIEBs is that the dynamic stability of tall buildings could be ensured by selecting the braces so that the post-elastic stiffness of each storey be greater than the negative geometric stiffness, thus counteracting P-Δ. In this presentation, the aptness of FIEBs for use as the seismic-force-resisting system of tall buildings is explored. To this effect, 40-, 30- and 20-storey prototype buildings are designed and modelled numerically and subjected to Non-Linear Response History Analysis. The results show that these buildings respond satisfactorily to earthquake loading, suggesting that FIEBs are adequate as the seismic-force-resisting system of tall buildings. [ABSTRACT FROM AUTHOR]