An equivalent linear procedure for probabilistic displacement-based design of RC structures under earthquake

Abstract

Starting from an already existing gradient-based method for the performance-based seismic design (PBSD) of reinforced concrete (RC) structures, in which performance objectives are formulated in terms of maximum accepted mean annual frequency (MAF) of exceedance for multiple limit states, some improvements are presented. The method allows for the computation of the values of selected independent design variables (beams and column cross-sections and reinforcement) leading to the attainment or non-exceedance of pre-defined MAFs for multiple limit states. General geometric, as well as capacity design constraints are duly accounted for. The procedure is applied to a 15-storey plane frame building and validation is conducted against results in terms of drift profiles and MAF of exceedance, obtained by multiple stripe analysis with records selected to match conditional spectra. Results show that the method is suitable for PBSD of RC structures with explicit targets in terms of desired risk levels.