A Computational Strategy for Eurocode 8-Compliant Analyses of Reinforced Concrete Structures by Seismic Envelopes

Abstract

ABSTRACT A procedure is presented for performing Eurocode 8-compliant spectral analyses of reinforced concrete structures by means of seismic response envelopes. To account for global torsion effects in the computation of the supreme envelope an algorithmic rotational response spectrum is defined. The presented strategy turns out to be particularly appropriate for finite element models including accidental eccentricity due to mass shifting since seismic envelopes can be computed by making reference to a single structural model rather than to separate models characterized by different signs of the accidental eccentricity. The proposed procedure is theoretically formulated and numerically tested by analyzing a rotationally stiff and a rotationally flexible building as well as two irregular structures. Moreover, it is compared with an alternative formulation derived from a recently proposed strategy concerning accidental torsion. The results show that the proposed procedure is coherent with the analysis procedures provided by standard codes and computationally more efficient.